Title of Invention	"STORAGE MEDIUM, REPRODUCING METHOD, AND RECORDING METHOD."
Abstract	According to one embodiment, a storage medium comprises a transparent resin substrate on which a groove is formed, a recording layer formed on the groove on the transparent resin substrate, the recording layer using an organic dye material and recording information with a light beam of 620 nm or less in wavelength, a reflection layer formed on the recording layer, and a prevention layer formed between the recording layer and the reflection layer, the prevention layer preventing degradation of characteristics of the reflection layer.

Title of Invention

"STORAGE MEDIUM, REPRODUCING METHOD, AND RECORDING METHOD."

Abstract

According to one embodiment, a storage medium comprises a transparent resin substrate on which a groove is formed, a recording layer formed on the groove on the transparent resin substrate, the recording layer using an organic dye material and recording information with a light beam of 620 nm or less in wavelength, a reflection layer formed on the recording layer, and a prevention layer formed between the recording layer and the reflection layer, the prevention layer preventing degradation of characteristics of the reflection layer.

Full Text	TITLE OF THE INVENTION STORAGE MEDIUM, REPRODUCING METHOD, AND RECORDING METHOD BACKGROUND OF THE INVENTION One embodiment of the invention relates to a storage medium such as an optical disk, a reproducing method, and a recording method of the storage medium capable of recording and reproducing information with a laser light beam having a short wavelength such as a blue laser light beam. As is well known, in recent years, with prevalence of personal computers or the like, media for accumulating digital data has been increasingly important. For example, currently, an information storage medium capable of digitally recording and reproducing video image information and voice information or the like for a long time is prevalent. In addition, an information storage medium for digital recording and reproduction is used for a mobile device such as a cellular phone. As an information storage medium of this type, there is often utilized a medium of disk shape because the medium has a large capacity of recording information; has random access performance capable of speedily making a search for desired recording information; and moreover, the medium is small in size and light in weight, excellent in storage property and portability, and is inexpensive. In addition, as an information storage medium of such a disk shape, currently, there is mainly used a so called optical disk capable of recording and reproducing information in a non-contact manner by irradiating a laser light beam. This optical disk primarily conforms to a CD (Compact Disk) standard or a DVD (Digital Versatile Disk) standard, and is compatible with both of these standards. There are three types of optical disks, i.e., a read-only type which cannot record information such as a CD-DA (Digital Audio), a CD-ROM (Read-Only Memory), a DVD-V (Video), or a DVD-ROM and the like; a write-once type capable of recording information only once such as a CD-R (Recordable) or a DVD-R and the like; and a rewritable type capable of rewriting information any times such as a CD-RW (Rewritable) or a DVD-RW and the like. Among them, as a recordable disk, a write-once type optical disk using an organic dye for a recording layer is the most prevalent because of its low manufacturing cost. This is because, if an information recording capacity exceeds 700 MB (Mega Bytes), there is almost no need for erasing recorded information and rewriting new information, and eventually only one recording suffices. In the write-once type optical disk using the organic dye for the recording layer, after a recording area (track) specified by a groove is irradiated with a laser light beam and a resin substrate is excessively heated to its glass transition point Tg or more, an organic dye film in the groove causes an opto-chemical reaction and produces a negative pressure. As a result, the resin substrate is deformed in the groove. A recording mark is formed by utilizing this deformation. A typical organic dye used for a CD-R whose wavelength of a recording and reproducing laser light beam is about 780 nm includes a phthalocyanine based dye such as IRGAPHOR Ultragreen MX available from Ciba Speciality Chemicals. In addition, a typical organic dye used for a DVD-R whose wavelength of a recording and reproducing laser light beam is about 650 nm includes an azo metal complex based dye available from Mitsubishi Kagaku Media Co., Ltd. In the meantime, in comparison with a current optical disk, in a next generation optical disk which achieves recording and reproduction with higher density and higher performance, a blue laser light beam whose wavelength is short at about 405 nm is used as a recording and reproducing laser light beam. However, an organic dye material capable of obtaining practically sufficient recording and reproducing characteristics by using a light beam having such a short wavelength has not been developed yet. In document 1 (Jpn. Pat. Appln. KOKAI Publication No. 2002-74740), there is disclosed an optical storage medium having a longer wavelength than a wavelength of a write light beam in absorption extremity of an organic dye compound contained in a recording layer. However, in this document 1, for example, there is nowhere described a configuration of enhancing performance of an optical disk itself such as durability in the case where a mark recorded in an optical disk has been continuously reproduced by a blue laser light pickup. There is a need for a signal not to be degraded in the case where a certain track is continuously reproduced. A write-once type optical disk using an excellent dye in reproduction light stability must be provided. In document 2 (Jpn. Pat. Appln. KOKAI Publication No. 2004-139712), there is disclosed an Ag-group alloy reflection film or a semipermeable reflection film for an optical information recording medium, the Ag-group alloy reflection film being made of an Ag-group alloy containing 0.005 at% to 0.40 at% of Bi and/or Sb in total. However, document 2 merely discloses a reflection film simplex, and does not describe how an organic dye component is used as a recording layer and how the above-described storage medium is configured as using a recording and reproducing light beam having a short wavelength. As has been described above, a conventional storage medium using an organic dye material is not sufficient in reproduction durability count. BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS A general architecture that implements the various feature of the invention will now be described with reference to the drawings. The drawings and the associated descriptions are provided to illustrate embodiments of the invention and not to limit the scope of the invention. FIG. 1 is an exemplary view of the contents of constituent elements of an information storage medium and a combination method in the present embodiment; FIGS. 2A, 2B, and 2C show exemplary views of difference in principle of obtaining reproduction signal between phase change type recording film and organic dye based recording film in which FIG. 2A shows a phase change type recording film and FIG. 2B shows an organic dye based recording film; FIG. 3 is an exemplary view showing a specific structural formula of the specific content "(A3) azometal complex + Cu" of the information storage medium constituent elements shown in FIG. 1; FIG. 4 is an exemplary view showing an example of light absorption spectrum characteristics of an organic dye recording material used for a current DVD-R disk; FIGS. 5A and 5B show exemplary views of difference of light reflection layer shape in pre-pit/pre-groove areas between phase change type recording film and organic dye based recording film in which FIG. 5A shows a phase change recording film and FIG. 5B shows an organic dye recording film; FIGS. 6A and 6B are exemplary views each showing a plastic deformation situation of a specific transparent substrate 2-2 at a position of a recording mark 9 in a write-once type information storage medium using a conventional organic dye material; FIGS. 7A, 7B and 7C are exemplary views which relate to a shape or dimensions relating to a recording film, which easily causes a principle of recording; FIGS. 8A, 8B and 8C are exemplary views showing characteristics of the shape and dimensions of the recording film; FIG. 9 is an exemplary view of light absorption spectrum characteristics in an unrecorded state in a "High to Low" (hereinafter, abbreviated to as an "H-L") recording film; FIG. 10 is an exemplary view of light absorption spectrum characteristics in a recording mark in the "HL" recording film; FIG. 11 is an exemplary view of a structure in an embodiment of an information recording/reproducing apparatus according to the invention; FIG. 12 is an exemplary view showing a detailed structure of peripheral sections including a sync code position sampling unit 145 shown in FIG. 11; FIG. 13 is an exemplary view showing a signal processor circuit using a slice level detecting system; FIG. 14 is an exemplary view showing a detailed structure in a slicer 310 of FIG. 13; FIG. 15 is an exemplary view showing a signal processor circuit using a PRML detecting technique; FIG. 16 is an exemplary view showing a structure in a Viterbi decoder 156 shown in FIG. 11 or FIG. 15; FIG. 17 is an exemplary view showing a state transition in a PR(1, 2, 2, 2, 1) class; FIG. 18 is an exemplary view showing a wavelength (write strategy) of a recording pulse which carries out trial writing for a drive test zone; FIG. 19 is an exemplary view showing a definition of a recording pulse shape; FIGS. 20A, 20B and 20C are exemplary views of a recording pulse timing parameter setting table; FIGS. 21A, 21B and 21C are exemplary views relating to values of each parameter used when optimal recording power is checked; FIG. 22 is an exemplary view showing a light reflection factor range of non-recording unit in an "H-L" recording film and a "Low to High" (hereinafter, abbreviated to as an "L-H") recording film; FIG. 23 is an exemplary view of a polarity of a detection signal detected from the "H-L" recording film and the "L-H" recording film; FIG. 24 is an exemplary view showing a comparison in light reflection factor between the "H-L" recording film and the "L-H" recording film; FIG. 25 is an exemplary view of light absorption spectrum characteristics in an unrecorded state in the "L-H" recording film; FIG. 26 is an exemplary view showing a light absorption spectrum characteristic change in a recorded state and an unrecorded state in the "L-H" recording film; FIG. 27 is an exemplary general structural formula of a cyanine dye utilized for a cation portion of the "L-H" recording film; FIG. 28 is an exemplary general structural formula of a styril dye utilized for a cation portion of the "L-H" recording film; FIG. 29 is an exemplary general structural formula of a monomethine cyanine dye utilized for a cation portion of the "L-H" recording film; FIG. 30 an exemplary general structural formula of a formazane metal complex utilized for an anion portion of the "L-H" recording film; FIG. 31 is an exemplary view showing an example of a structure and dimensions in an information storage medium; FIG. 32 is an exemplary view showing a value of a general parameter in a read-only type information storage medium; FIG. 33 is an exemplary view showing a value of a general parameter in a write-once type information storage medium; FIG. 34 is an exemplary view showing a value of a general parameter in a rewritable type information storage medium; FIGS. 35A, 35B and 35C are exemplary views comparing a detailed data structure in a system lead-in area SYLDI and a data lead-in area DTLDI in a variety of information storage mediums; FIG. 36 is an exemplary view showing a data structure in an RMD deprecation zone RDZ and a recording position management zone RMZ, which exist in the write-once type information storage medium; FIGS. 37A, 37B, 37C, 37D, 37E and 37F are exemplary views each showing a comparison of a data structure in a data area DTA and a data lead-out area DTLDO in a variety of information storage mediums; FIG. 38 is an exemplary view showing a data structure in recording position management data RMD; FIG. 39 is an exemplary view showing a structure of a border area in a write-once type information storage medium different from that in FIG. 38; - 10 - FIG. 40 is an exemplary view showing a structure of a border area in a write-once type information storage medium; FIG. 41 is an exemplary view showing a data structure in a control data zone CDZ and an R physical information zone RIZ; FIG. 42 is an exemplary view showing specific information contents in physical format information PFI and R physical information format information R_PFI; FIG. 43 is an exemplary view showing a comparison of the contents of detailed information recorded in allocation place information on a data area DTA; FIG. 44 is an exemplary view showing a detailed data structure in recording position management data RMD; FIG. 45 is an exemplary view showing a detailed data structure in recording position management data RMD; FIG. 46 is an exemplary view showing a detailed data structure in recording position management data RMD; FIG. 47 is an exemplary view showing a detailed data structure in recording position management data RMD; FIG. 48 is an exemplary view showing a detailed data structure in recording position management data RMD; FIG. 49 is an exemplary view showing a detailed data structure in recording position management data RMD; FIG. 50 is an exemplary view showing a data structure in a data ID; FIG. 51 is an exemplary view adopted to explain another embodiment relevant to a data structure in recording position management data RMD; FIG. 52 is an exemplary view adopted to explain the other embodiment relevant to a data structure in recording position management data RMD; FIG. 53 is an exemplary view showing another data structure in an RMD field 1; FIG. 54 is an exemplary view of another embodiment relating to physical format information and R physical format information. FIG. 55 is an exemplary view showing another embodiment relating to a data structure in a control data zone; FIG. 56 is an exemplary view schematically showing converting procedures for configuring a physical sector structure; FIG. 57 is an exemplary view showing a structure in a data frame; FIGS. 58A and 58B are exemplary views each showing an initial value assigned to a shift register when creating a frame after scrambled and a circuit configuration of a feedback resistor; FIG. 59 is an exemplary view of an ECC block structure; FIG. 60 is an exemplary view of a frame arrangement after scrambled; FIG. 61 is an exemplary view of a PO interleaving method; FIGS. 62A and 62B are exemplary views each showing a structure in a physical sector; FIG. 63 is an exemplary view of the contents of a sync code pattern; FIG. 64 is an exemplary view showing a detailed structure of an ECC block after PO interleaved, shown in FIG. 61; FIG. 65 is an exemplary view showing an example of a light absorption spectrum characteristic change before and after recorded, in an "H-L" recording film; FIG. 66 is an exemplary view showing an example of a light absorption spectrum characteristic change before and after recorded, in an "L-H" recording film; FIGS. 67A and 67B are exemplary views each showing a molecular structure changing situation in an azo metal complex; FIG. 68 is an exemplary view showing another example of a light absorption spectrum change before and after recorded, in an "L-H" recording film; FIG. 69 is an exemplary view showing another example of a light absorption spectrum change before and after recorded, in an "H-L" recording film; FIG. 70 is an exemplary view showing still another example of a light absorption spectrum change before and after recorded, in an "H-L" recording film; FIGS. VIA and 71B are exemplary illustrative cross section of a pre-pit in a system lead-in area SYLDI; FIG. 72 is an exemplary view of a reference code pattern; FIG. 73 is an exemplary view showing a comparison in data recording format of each of a variety of information storage mediums; FIGS. 74A and 74B are exemplary views of a comparison with a conventional example of a data structure in a variety of information storage mediums; FIG. 75 is an exemplary view of a comparison with a conventional example of a data structure in a variety of information storage mediums; FIG. 76 is an exemplary view of 180-degree phase modulation and an NRZ technique in wobble modulation; FIG. 77 is an exemplary view of a relationship between a wobble shape and an address bit in an address bit area; FIGS. 78A, 78B, 78C and 78D are comparative exemplary views of a positional relationship in a wobble sink pattern and a wobble data unit; FIG. 79 is an exemplary view relating to a data structure in wobble address information contained in a write-once type information storage medium; FIG. 80 is an exemplary view of an allocation place in a modulation area on a write-once type information storage medium; FIG. 81 is an exemplary view showing an allocation place in a physical segment on a write-once type information storage medium; FIGS. 82A and 82B are exemplary views of a layout in a recording cluster; FIG. 83 is an exemplary view showing a data recording method for rewritable data recorded on a rewritable-type information storage medium; FIG. 84 is an exemplary view of a data random shift of the rewritable data recorded on a rewritabletype information storage medium; FIG. 85 is an exemplary view of a method for additionally describing write-once type data recorded on a write-once type information storage medium; FIG. 86 is an exemplary view of specification of an optical disk in B format; FIG. 87 is a view showing an exemplary configuration of picket codes (error correcting blocks in the B format; FIG. 88 is an exemplary view of a wobble address in B format; FIG. 89 is an exemplary view showing a detailed structure of a wobble address obtained by combining an MSK system and an STW system with each other; FIG. 90 is an exemplary view showing a unit of 56 wobbles and an ADIP unit expressing a bit of "0" or "1"; FIG. 91 is an exemplary view showing an ADIP word consisting of 83 ADIP units and showing an address; FIG. 92 is an exemplary view showing an ADIP word; FIG. 93 is an exemplary view showing 15 nibbles contained in an ADIP word; FIG. 94 is an exemplary view showing a track structure in B format; FIG. 95 is an exemplary view showing a recording frame in B format; FIGS. 96A and 96B are exemplary views each showing a structure of a recording unit block; FIG. 97 is an exemplary view showing data run in and data run out structures; FIG. 98 is an exemplary view showing allocation of data relating to a wobble address; FIGS. 99A and 99B are exemplary views each showing an area of guard 3 arranged at the end of a data run out area; FIGS. 100A, 100B, 100C, 100D, 100E, and 100F are exemplary views showing a method for producing a writeonce type information storage medium; FIGS. 101A, 101B, and 101C are exemplary views showing a method for producing a stamper for producing a write-once type information storage medium; FIGS. 102A, 102B, 102C, 102D, and 102E are exemplary views showing a method for producing a stamper for producing a write-once type information storage medium; FIG. 103 is an exemplary view showing a spin coat condition for producing a write-once type information storage medium; FIG. 104 is an exemplary a view illustrating a relationship between a groove and a land in a writeonce type information storage medium; FIG. 105 is an exemplary a waveform chart showing an example of a signal recorded to carry out a test of recording and reproducing evaluation in a write-once type information storage medium; FIG. 106 is an exemplary view showing a general structural formula of organic metal complex simplex "A" ; FIG. 107 is an exemplary view showing a general structural formula of organic metal complex simplex B; FIG. 108 is an exemplary view showing a general structural formula of organic dye metal complex cation and anion U; FIG. 109 is an exemplary view showing a general structural formula of organic dye metal complex cation and anion W; FIG. 110 is an exemplary view showing a general structural formula of azo phthalocyanine metal complex Y; FIG. Ill is an exemplary view showing an example Ul of organic dye metal complex cation and anion U; FIG. 112 is an exemplary view showing an example Wl of organic metal complex cation and anion W; FIG. 113 is an exemplary view showing a formazane metal complex V; FIG. 114 is an exemplary view showing an example of organic metal complex cation and anion W; FIG. 115 is an exemplary view showing a general structural formula of organic metal complex cation and anion WW; FIG. 116 is an exemplary view showing a general structural formula of organic metal complex cation and anion WWW; FIG. 117 is an exemplary view showing a general structural formula of organic metal complex cation and anion WWWW; FIG. 118 is an exemplary view showing an example of organic metal complex cation and anion WW1; FIG. 119 is an exemplary view showing an example of organic metal complex cation and anion WWWl; FIG. 120 is an exemplary view showing an example of organic metal complex cation and anion WWWWl; FIG. 121 is an exemplary view showing an example of organic metal complex cation and anion WWWW2; FIG. 122 is an exemplary view showing a relationship (measurement result) between reproduction laser power and reproduction durability count for each organic dye material; FIG. 123 is an exemplary view showing examples of binary types; FIG. 124 is an exemplary view showing examples of tertiary types; FIG. 125 is an exemplary view showing comparative examples; FIG. 126 is an exemplary view showing combinations of reflection film materials and constitution and organic dye materials for recording films of example 1; FIG. 127 is an exemplary view showing evaluation results of example 1; FIG. 128 is an exemplary view showing combinations of reflection film materials and constitution and organic dye materials for recording films of example 1; and FIG. 129 is an exemplary view showing evaluation results of example 2. DETAILED DESCRIPTION OF THE INVENTION Various embodiments according to the invention will be described hereinafter with reference to the accompanying drawings. In general, according to one embodiment of the invention, a storage medium comprises a recording layer using an organic dye material formed on a substrate; and a reflection layer comprises Ag and an additive element which prevents degradation of recording and reproducing characteristics due to reaction with Ag and the organic dye material. Hereinafter, embodiments of a recording medium and a method for recording and reproducing the recording medium according to the invention will be described with reference to the accompanying drawings. Summary of characteristics and advantageous effect of the invention 1) Relationship between track pitch/bit pitch and optimal recording power: Conventionally, in the case of a principle of recording with a substrate shape change, if a track pitch is narrowed, a "cross-write" or a "cross-erase" occurs, and if bit pitches are narrowed, an inter-code crosstalk occurs. As in the present embodiment, since a principle of recording without a substrate shape change is devised, it becomes possible to achieve high density by narrowing track pitches/bit pitches. In addition, at the same time, in the above described principle of recording, recording sensitivity is improved, enabling high speed recording and multilayering of a recording film because optimal recording power can be lowly set. 2) In optical recording with a wavelength of 620 nm or less, an ECC block is composed of a combination of a plurality of small ECC blocks and each item of data ID information in two sectors is disposed in a small ECC block which is different from another: According to the embodiment, as shown in FIG. 2B, a local optical characteristic change in a recording layer 3-2 is a principle of recording, and thus, an arrival temperature in the recording layer 3-2 at the time of recording is lower than that in the conventional principle of recording due to plastic deformation of a transparent substrate 2-2 or due to thermal decomposition or gasification (evaporation) of an organic dye recording material. Therefore, a difference between an arrival temperature and a recording temperature in a recording layer 3-2 at the time of playback is small. In the present embodiment, an interleaving process between small ECC blocks and data ID allocation are contrived in one ECC block, thereby improving reproduction reliability in the case where a recording film is degraded at the time of repetitive playback. 3) Recording is carried out by light having a wavelength which is shorter than 620 nm, and a recorded portion has a higher reflection factor than a nonrecording portion: Under the influence of absorption spectrum characteristics of a general organic dye material, under the control of light having a wavelength which is shorter than 620 nm, the light absorbance is significantly lowered, and recording density is lowered. Therefore, a very large amount of exposure is required to generate a substrate deformation which is a principle of recording in a conventional DVD-R. By employing an "Low to High (hereinafter, abbreviated to as L-H) organic dye recording material" whose reflection factor is increased more significantly than that of an unrecorded portion in a portion (recording mark) recorded as in the present embodiment, a substrate deformation is eliminated by forming a recording mark using a "discoloring action due to dissociation of electron coupling", and recording sensitivity is improved. 4) "L-H" organic dye recording film and PSK/FSK modulation wobble groove: Wobble synchronization at the time of playback can be easily obtained, and reproduction reliability of a wobble address is improved. 5) "L-H" organic dye recording film and reproduction signal modulation degree rule: A high C/N ratio relating to a reproduction signal from a recording mark can be ensured, and reproduction reliability from the recording mark is improved. 6) Light reflection factor range in "L-H" organic dye recording film and mirror section: A high C/N ratio relating to a reproduction signal from a system lead-in area SYLDI can be ensured and high reproduction reliability can be ensured. 7) "L-H" organic dye recording film and light reflection factor range from unrecorded area at the time of on-track: A high C/N rate relating to a wobble detection signal in an unrecorded area can be ensured, and high reproduction reliability relevant to wobble address information can be ensured. 8) "L-H" organic dye recording film and wobble detection signal amplitude range: A high C/N ratio relating to a wobble detection signal can be ensured, and high reproduction reliability relevant to wobble address information can be ensured. «Table of Contents» Chapter 0: Description of Relationship between Wavelength and the Present Embodiment Wavelength used in the present embodiment. Chapter 1: Description of Combination of Constituent Elements of Information Storage Medium in the Present Embodiment: FIG. 1 shows an illustration of the contents of constituent elements of the information storage medium in the present embodiment. Chapter 2: Description of Difference in reproduction signal between Phase Change Recording Film and Organic Dye Recording Film 2-1) Difference in Principle of Recording/Recording Film and Difference in Basic Concept Relating to Generation of Reproduction Signal . . . Definition of A,max Write 2-2) Difference of Light Reflection Layer Shape in Pre-pit/Pre-groove Area Optical reflection layer shape (difference in spin coating and sputtering vapor deposition) and influence on a reproduction signal. Chapter 3: Description of Characteristics of Organic Dye Recording Film in the Present Embodiment 3-1) Problem(s) relevant to achievement of high density in write-once type recording film (DVD-R) using conventional organic dye material 3-2) Description of basic characteristics common to organic dye recording films in the present embodiment: Lower limit value of recording layer thickness, channel bit length/track pitch in which advantageous effect is attained in the invention, repetitive playback enable count, optimal reproduction power, Rate between groove width and land width Relationship with wobble address format Relationship in recording layer thickness between groove section and land section Technique of improving error correction capability of recording information and combination with PRML 3-3) Recording characteristics common to organic dye recording films in the present embodiment Upper limit value of optimal recording power 3-4) Description of characteristics relating to a "High to Low (hereinafter, abbreviated to as H-L)" recording film in the present embodiment: Upper limit value of reflection factor in unrecorded layer Relationship between a value of X,max write anc^ a value oflmax (absorbance maximum wavelength at unrecorded/recorded position) Relative values of reflection factor and degree of modulation at unrecorded/recorded position and light absorption values at reproduction wavelength ... n-k range Relationship in upper limit value between required resolution characteristics and recording layer thickness Chapter 4:Description of Reproducing Apparatus or Recording/Reproducing Apparatus and Recording Condition/Reproducing Circuit 4-1) Description of structure and characteristics of reproducing apparatus or recording/reproducing apparatus in the present embodiment: Use wavelength range, NA value, and RIM intensity 4-2) Description of reproducing circuit in the present embodiment 4-3) Description of recording condition in the present embodiment Chapter 5: Description of Specific Embodiments of Organic Dye Recording Film in the Present Embodiment 5-1) Description of characteristics relating to "L-H" recording film in the present embodiment Principle of recording and reflection factor and degree of modulation at unrecorded/recorded position 5-2) Characteristics of light absorption spectra relating to "L-H" recording film in the present embodiment: Condition for setting maximum absorption wavelength ^max write' value of ^1495 and a value of Ah405 5-3) Anion portion: Azo metal complex + cation portion: Dye 5-4) Use of "copper" as azo metal complex + main metal: Light absorption spectra after recorded is widen in a "H-L" recording film, and is narrowed in a "L-H" recording film. Upper limit value of maximum absorption wavelength change amount before and after recording: A maximum absorption wavelength change amount before and after recording is small, and absorbance at a maximum absorption wavelength changes. Chapter 6:Description Relating to Pre-groove shape/pre-pit shape in coating type organic dye recording film and on light reflection layer interface 6-1) Light reflection layer (material and thickness) : Thickness range and passivation structure ... Principle of recording and countermeasures against degradation (Signal is degraded more easily than substrate deformation or than cavity) 6-2) Description relating to pre-pit shape in coating type organic dye recording film and on light reflection layer interface: Advantageous effect achieved by widening track pitch/channel bit pitch in system lead-in area: Reproduction signal amplitude value and resolution in system lead-in area: Rule on step amount at land portion and pre-pit portion in light reflection layer 4-2: 6-3) Description relating to pre-groove shape in coating type organic dye recording film and on light reflection layer interface: Rule on step amount at land portion and pre-groove portion in light reflection layer 4-2: Push-pull signal amplitude range: Wobble signal amplitude range (combination with wobble modulation system) Chapter 7: Description of First Next-Generation Optical Disk: HD DVD System (Hereinafter, Referred to as H Format): Principle of recording and countermeasure against reproduction signal degradation (Signal is degraded more easily than substrate deformation or than cavity): Error Correction Code (ECC) structure, PRML (Partial Response Maximum Likelihood) System: Relationship between a wide flat area in the groove and wobble address format. In the write-once recording, overwriting is carried out in a VFO area which is non-data area. Influence of DC component change in overwrite area is reduced. In particular, advantageous effect on "LH" recording film is significant. Chapter 8: Description of Second Next-Generation Optical Disk: B format Principle of recording and countermeasures against reproduction signal degradation (Signal is degraded more easily than substrate deformation or cavity). Relationship between a wide flat area in the groove and wobble address format In the write-once recording, overwriting is carried out in a VFO area which is a non-data area. Influence of DC component change in overwrite area is reduced. In particular, advantageous effect in "LH" recording film is significant. Now, a description of the present embodiment will be given here. Chapter 0:Description of Relationship between Use Wavelength and the Present Embodiment As a write-once type optical disk obtained by using an organic dye material for a recording medium, there has been commercially available a CD-R disk using a recording/reproducing laser light source wavelength of 780 nm and a DVD-R disk using a recording/reproducing laser light beam wavelength of 650 nm. Further, in a next-generation write-once type information storage medium having achieved high density, it is proposed that a laser light source wavelength for recording or reproducing, which is close to 405 nm (namely, in the range of 355 nm to 455 nm), is used in either of H format (Dl) and B format (D2) of FIG. 1 described later. In a write-once type information storage medium using an organic dye material, recording/reproducing characteristics sensitively changes due to a slight change of a light source wavelength. In principle, density is increased in inverse proportion to a square of a laser light source wavelength for recording/reproducing, and thus, it is desirable that a shorter laser light source wavelength be used for recording/reproducing. However, for the above described reason, an organic dye material utilized for a CD-R disk or a DVD-R disk cannot be used as a write-once type information storage medium for 405 nm. Moreover, because 405 nm is close to an ultraviolet ray wavelength, there can easily occur a disadvantage that a recording material "which can be easily recorded with a light beam of 405 nm", is easily changed in characteristics due to ultraviolet ray irradiation, lacking a long period stability. Characteristics are significantly different from each other depending on organic dye materials to be used, and thus, it is difficult to determine the characteristics of these dye materials in general. As an example, the foregoing characteristics will be described by way of a specific wavelength. With respect to an organic dye recording material optimized with a light beam of 650 nm in wavelength, the light to be used becomes shorter than 620 nm, recording/reproducing characteristics significantly change. Therefore, in the case where a recording/reproducing operation is carried out with a light beam which is shorter than 620 nm in wavelength, there is a need for new development of an organic dye material which is optimal to a light source wavelength of recording light or reproducing light. An organic dye material of which recording can be easily carried out with a light beam shorter than 530 nm in wavelength easily causes characteristic degradation due to ultraviolet ray irradiation, lacking long period stability. In the present embodiment, a description will be given with respect to an embodiment relevant to an organic recording material suitable to use in close to 405 nm. Namely, a description will be given with respect to an embodiment relating to an organic recording material which can be stably used in the range of 355 nm to 455 nm in consideration of a fluctuation of a light emitting wavelength which depends on manufacturers of semiconductor laser light sources. That is, the scope of the present embodiment corresponds to a light beam which is adapted to a light source of 620 nm in wavelength, and desirably, which is shorter than 530 nm in wavelength (ranging from 355 nm to 455 nm in a definition in the narrowest range). In addition, the optical recording sensitivity due to light absorption spectra of an organic dye material is also influenced by a recording wavelength. An organic dye material suitable for long period stability is easily reduced in light absorbance relevant to a light beam which is shorter than 620 nm in wavelength. In particular, the light absorbance is significantly lowered with respect to a light beam which is shorter than 620 nm in wavelength, and in particular, is drastically reduced with respect to a light beam which is shorter than 530 nm in wavelength. Therefore, in the case where recording is carried out with a laser light beam ranging from 355 nm to 455 nm in wavelength, which is the severest condition, recording sensitivity is impaired because the light absorbance is low, and there is a need for a new design employing a new principle of recording as shown in the present embodiment. The size of a focusing spot used for recording or reproducing application is reduced in proportion to a wavelength of a light beam to be used. Therefore, from only a standpoint of the focusing spot size, in the case where a wavelength is reduced to the above described value, an attempt is made to reduce a track pitch or channel bit length by a wavelength component with respect to a current DVD-R disk (use wavelength: 650 ran) which is a conventional technique. However, as described later in "3-2-A] Scope requiring application of technique according to the present embodiment", as long as a principle of recording in a conventional write-once type information storage medium such as a DVD-R disk is used, there is a problem that a track pitch or a channel bit length cannot be reduced. A track pitch or a channel bit length can be reduced in proportion to the above described wavelength by utilizing a technique devised in the present embodiment described below. Chapter 1: Description of Combination of Constituent Elements of Information Storage Medium in the Present Embodiment In the present embodiment, there exists a great technical feature in that an organic recording medium material (organic dye material) adapted to a light source of 620 nm or less in wavelength has been devised. Such an organic recording medium (organic dye material) has a unique characteristic (Low to High characteristic) that a light reflection factor increases in a recording mark, which does not exist in a conventional CD-R disk or a DVD-R disk. Therefore, a technical feature of the present embodiment and a novel effect attained thereby occurs in a structure, dimensions, or format (information recording format) combination of the information storage medium which produces more effectively the characteristics of the organic recording material (organic dye materials) shown in the present embodiment. FIG. 1 shows a combination, which produces a new technical feature and advantageous effect in the present embodiment. That is the information storage medium in the present embodiment has the following constituent elements: A] an organic dye recording film; B] a pre-format (such as pre-groove shape/dimensions or pre-pit shape/dimensions); C] a wobble condition (such as wobble modulation method and wobble change shape, wobble amplitude, and wobble allocating method); and D] a format (such as format for recording data which is to be recorded or which has been recorded in advance in information storage medium). Specific embodiments of constituent elements correspond to the contents described in each column of FIG. 1. A technical feature and a unique advantageous effect of the present embodiment occur in combination of the specific embodiments of the constituent elements shown in FIG. 1. Hereinafter, a description will be given with respect to a combination state of individual embodiments at a stage of explaining the embodiments. With respect to constituent elements, which do not specify a combination, it denotes that the following characteristics are employed: A5) an arbitrary coating recording film; B3) an arbitrary groove shape and an arbitrary pit shape; C4) an arbitrary modulation system; C6) an arbitrary amplitude amount; and D4) an arbitrary recording method and a format in a write-once medium. Chapter 2: Description of Difference in reproduction signal between Phase Change Recording Film and Organic Dye Recording Film 2-1) Difference in Principle of Recording/Recording Film and Difference in Basic Concept Relating to Generation of Reproduction Signal FIG. 2A shows a standard phase change recording film structure (mainly used for a rewritable-type information storage medium), and FIG. 2B shows a standard organic dye recording film structure (mainly used for a write-once type information storage medium) In the description of the present embodiment, a whole recording film structure excluding transparent substrates 2-1 and 2-2 shown in FIGS. 2A and 2B (including light reflection layers 4-1 and 4-2) is defined as a "recording film", and is discriminated from recording layers 3-1 and 3-2 in which a recording material is disposed. With respect to a recording material using a phase change, in general, an optical characteristic change amount in a recorded area (in a recording mark) and an unrecorded area (out of a recording mark) is small, and thus, there is employed an enhancement structure for enhancing a relative change rate of a reproduction signal. Therefore, in a phase change recording film structure, as shown in FIG. 2A, an undercoat intermediate layer 5 is disposed between the transparent substrate 2-1 and a phase change type recording layer 3-1, and an upper intermediate layer 6 is disposed between the light reflection layer 4-2 and the phase change type recording layer 3-1. In the invention, as a material for the transparent substrates 2-1 and 2-2, there is employed a polycarbonate PC or an acrylic PMMA (poly methyl methacrylate) which is a transparent plastic material. A center wavelength of a laser light beam 7 used in the present embodiment is 405 nm, and refractive index r\2i, 22 tne polycarbonate PC at this wavelength is close to 1.62. Standard refractive index ni and absorption coefficient ki in 405 nm at GeSbTe (germanium antimony tellurium) which is most generally used as a phase change type recording material are ni =? 1.5 and k-i =? 2.5 in a crystalline area, whereas they are ni = 2.5 and ki =? 1.8 in an amorphous area. Thus, a refractive index (in the amorphous area) of a phase change type recording medium is different from a refractive index of the transparent substrate 2-1, and reflection of a laser light beam 7 on an interface between the layers is easily occurred in a phase change recording film structure. As described above, for the reasons why (1) a phase change recording film structure takes an enhancement structure; and (2) a refractive index difference between the layers is great or the like, a light reflection amount change at the time of reproduction from a recording mark recorded in a phase change recording film (a differential value of a light reflection amount from a recording mark and a light reflection amount from an unrecorded area) can be obtained as an interference result of multiple reflection light beams generated on an interface between the undercoat intermediate layer 5, the recording layer 3-1, the upper intermediate layer 6, and the light reflection layer 4-2. In FIG. 2A, although the laser light beam 7 is apparently reflected on an interface between the undercoat intermediate layer 5 and the recording layer 3-1, an interface between the recording layer 3-1 and the upper intermediate layer 6, and an interface between the upper intermediate layer 6 and the light reflection layer 4-2, in actuality, a reflection light amount change is obtained as an interference result between a plurality of multiple reflection light beams. In contrast, an organic dye recording film structure takes a very simple laminate structure made of an organic dye recording layer 3-2 and a light reflection layer 4-2. An information storage medium (optical disk) using this organic dye recording film is called a write-once type information storage medium, which enables only one time of recording. However, unlike a rewritable-type information storage medium using the phase change recording medium, this medium cannot carry out an erasing process or a rewriting process of information which has been recorded once. A refractive index at 405 nm of a general organic dye recording material is often close to n2 1-4 (n32 = 1.4 to 1.9 in the refractive index range at 405 nm of a variety of organic dye recording materials) and an absorption coefficient is often close to k2 0-2 0.1 to 0.2 in the absorption coefficient range at 405 nm of a variety of organic dye recording materials). Because a refractive index difference between the organic dye recording material and the transparent substrate 2-2 is small, there hardly occurs a light reflection amount on an interface between the recording layer 3-2 and the transparent substrate 2-2. Therefore, an optical reproduction principle of an organic color recording film (reason why a reflection light amount change occurs) is not "multiple interference" in a phase change recording film, and a main factor is a "light amount loss (including interference) midway of an optical path with respect to the laser light beam 7 which comes back after being reflected in the light reflection layer 4-2". Specific reasons which cause a light amount loss midway of an optical path include an "interference phenomenon due to a phase difference partially caused in the laser light 7" or an "optical absorption phenomenon in the recording layer 3-2". The light reflection factor of the organic dye recording film in an unrecorded area on a mirror surface on which a pre-groove or a pre-pit does not exist is featured to be simply obtained by a value obtained by subtracting an optical absorption amount when the recording layer 3-2 is passed from the light reflection factor of the laser light beam 7 in the light reflection layer 4-2. As described above, this film is different from a phase change recording film whose light reflection factor is obtained by calculation of "multiple interference". First, a description will be given with respect to a principle of recording, which is used in a current DVD-R disk as a conventional technique. In the current DVD-R disk, when a recording film is irradiated with the laser light beam 7, the recording layer 3-2 locally absorbs energy of the laser light beam 7, and becomes hot. If a specific temperature is exceeded, the transparent substrate 2-2 is locally deformed. Although a mechanism, which induces deformation of the transparent substrate 2-2, is different depending on manufacturers of DVD-R disks, it is said that this mechanism is caused by: 1) local plastic deformation of the transparent substrate 2-2 due to gasification energy of the recording layer 3-2; and 2) transmission of a heat from the recording layer 3-2 to the transparent substrate 2-2 and local plastic deformation of the transparent substrate 2-2 due to the heat. If the transparent substrate 2-2 is locally plastically deformed, there changes an optical distance of the laser light beam 7 reflected in the light reflection layer 4-2 through the transparent substrate 2-2, the laser light beam 7 coming back through the transparent substrate 2-2 again. A phase difference occurs between the laser light beam 7 from a recording mark, the laser light beam coming back through a portion of the locally plastically deformed transparent substrate 2-2, and a laser light beam 7 from the periphery of the recording mark, the laser light beam coming back through a portion of a transparent substrate 2-2 which is not deformed, and thus, a light amount change of reflection light beam occurs due to interference between these light beams. In addition, in particular, in the case where the above described mechanism of (1) has occurred, a change of a substantial refractive index n^2 produced by cavitation of the inside of the recording mark in the recording layer 3-2 due to gasification (evaporation), or alternatively, a change of a refractive index n2 produced due to thermal decomposition of an organic dye recording material in the recording mark, also contributes to the above described occurrence of a phase difference. In the current DVD-R disk, until the transparent substrate 2-2 is locally deformed, there is a need for the recording layer 3-2 becoming hot (i.e., at a gasification temperature of the recording layer 3-2 in the above described mechanism of (1) or at an internal temperature of the recording layer 3-2 required for plastically reforming the transparent substrate 2-2 in the mechanism of (2)) or there is a need for a part of the recording layer 3-2 becoming hot in order to cause thermal decomposition or gasification (evaporation). In order to form a recording mark, there is a need for large amount of power of the laser light beam 7. In order to form the recording mark, there is a necessity that the recording layer 3-2 can absorb energy of the laser light beam 7 at a first stage. The light absorption spectra in the recording layer 3-2 influence the recording sensitivity of an organic dye recording film. A principle of light absorption in an organic dye recording material which forms the recording layer 3-2 will be described with reference to (A3) of the present embodiment. FIG. 3 shows a specific structural formula of the specific contents "(A3) azo metal complex + Cu" of the constituent elements of the information storage medium shown in FIG. 1. A circular periphery area around a center metal M of the azo metal complex shown in FIG. 3 is obtained as a light emitting area 8. When a laser light beam 7 passes through this light emitting area 8, local electrons in this light emitting area 8 resonate to an electric field change of the laser light beam 7, and absorbs energy of the laser light beam 7. A value converted to a wavelength of the laser light beam with respect to a frequency of an electric field change at which these local electrons resonate most and easily absorbs the energy is called a maximum absorption wavelength, and is represented by A,max. As a range of the light emitting area 8 (resonation range) as shown in FIG. 3 increases, the maximum absorption wavelength ^max is shifted to the long wavelength side. In addition, in FIG. 3, the localization range of local electrons around the center metal M (how large the center metal M can attract the local electrons to the vicinity of the center) is changed by changing atoms of the center metal M, and the value of the maximum absorption wavelength A,max changes. Although it can be predicted that the light absorption spectra of the organic dye recording material in the case where there exists only one light emitting area 8 which is absolute 0 degree at a temperature and high in purity draws narrow linear spectra in close to a maximum absorption wavelength Xmax, the light absorption spectra of a general organic recording material including impurities at a normal temperature, and further, including a plurality of light absorption areas exhibit a wide light absorption characteristic with respect to a wavelength of a light beam around the maximum absorption wavelength X,max. FIG. 4 shows an example of light absorption spectra of an organic dye recording material used for a current DVD-R disk. In FIG. 4, a wavelength of a light beam to be irradiated with respect to an organic dye recording film formed by coating an organic dye recording material is taken on a horizontal axis, and absorbance obtained when an organic dye recording film is irradiated with a light beam having a respective wavelength is taken on a vertical axis. The absorbance used here is a value obtained by entering a laser light beam having incident intensity lo from the side of the transparent substrate 2-2 with respect to a state in which a write-once type information storage medium has been completed (or alternatively, a state in which the recording layer 3-2 has been merely formed on the transparent substrate 2-2 (a state that precedes forming of the optical reflection layer 4-2 with respect to a structure of FIG. 2B)), and then, measuring reflected laser light intensity Ir (light intensity It of the laser light beam transmitted from the side of the recording layer 3-2). The absorbance Ar (At) is represented by: Ar = -Iog10(lr/Io) (A-l) Ar = -logio(It/Io) (A-2) Unless otherwise specified, although a description will be given assuming that the absorbance denotes absorbance Ar of a reflection shape expressed by formula (A-l), it is possible to define absorbance At of a transmission shape expressed by formula (A-2) without being limited thereto in the present embodiment. In the embodiment shown in FIG. 4, there exist a plurality of light absorption areas, each of which includes the light emitting area 8, and thus, there exist a plurality of positions at which the absorbance becomes maximal. In this case, there exist a plurality of maximum absorption wavelength Xmax when the absorbance takes a maximum value. A wavelength of the recording laser light in the current DVD-R disk is set to 650 nm. In the case where there exist a plurality of the maximum absorption wavelengths the present embodiment, a value of the maximum absorption wavelength ^max which is the closest to the wavelength of the recording laser light beam becomes important. Therefore, only in the description of the present embodiment, the value of the maximum absorption wavelength A,max set at a position which is the closest to the wavelength of the recording laser light beam is defined as "A,max write"; and is discriminated from another Xmax (Xmax 0)• 2-2) Difference of light reflection layer shape in pre-pit/pre-groove area FIGS. 5A and 5B each show a comparison in shape when a recording film is formed in a pre-pit area or a pre-groove area 10. FIG. 5A shows a shape relevant to a phase change recording film. In the case of forming any of the undercoat intermediate layer 5, the recording layer 3-1, the upper intermediate layer 6, and the light reflection layer 4-1 as well, any of methods of sputtering vapor deposition, vacuum vapor deposition, or ion plating is used in vacuum. As a result, in all of the layers, irregularities of the transparent substrate 2-1 are duplicated comparatively faithfully. For example, in the case where a sectional shape in the pre-pit area or pre-groove area 10 of the transparent substrate 2-1 is rectangular or trapezoidal, the sectional shape of the recording layer 3-1 and the light reflection layer 4-1 each is also rectangular or trapezoidal. FIG. 5B shows a general recording film sectional shape of a current DVD-R disk which is a conventional technique as a recording film in the case where an organic dye recording film has been used. In this case, as a method for forming the recording film 3-2, there is used a method called spin coating (or spinner coating) which is completely different from that shown in FIG. 5A. The spin coating used here denotes a method for dissolving in an organic solvent an organic dye recording material which forms the recording layer 3-2; applying a coating onto the transparent substrate 2-2; followed by rotating the transparent substrate 2-2 at a high speed to spread a coating agent to the outer periphery side of the transparent substrate 2-2 by a centrifugal force; and gasifying the organic solvent, thereby forming the recording layer 3-2. Using this method, a process for coating the organic solvent is used, and thus, a surface of the recording layer 3-2 (an interface with the light reflection layer 2-2) is easily flattened. As a result, the sectional shape on the interface between the light reflection layer 2-2 and the recording layer 3-2 is obtained as a shape which is different from the shape of the surface of the transparent substrate 2-2 (an interface between the transparent substrate 2-2 and the recording layer 3-2). For example, in a pre-groove area in which the sectional shape of the surface of the transparent substrate 2-2 (an interface between the transparent substrate 2-2 and the recording layer 3-2) is rectangular or trapezoidal, the sectional shape on the interface between the light reflection layer 2-2 and the recording layer 3-2 is formed in a substantially V-shaped groove shape. In a pre-pit area, the above sectional shape is formed in a substantially conical side surface shape. Further, at the time of spin coating, an organic solvent is easily collected at a recessed portion, and thus, the thickness Dg of the recording layer 3-2 in the pre-pit area or pre-groove area 10 (i.e., a distance from a bottom surface of the pre-pit area or pre-groove area to a position at which an interface relevant to the light reflection layer 2-2 becomes the lowest) is larger than the thickness Dl in a land area 12 (Dg Dl). As a result, an amount of irregularities on an interface between the transparent substrate 2-2 and the recording area 3-2 in the pre-pit area or pre-groove area 10 becomes substantially smaller than an amount of irregularities on the transparent substrate 2-2 and the recording layer 3-2. As described above, the shape of irregularities on the interface between the light reflection layer 2-2 and the recording layer 3-2 becomes blunt and an amount of irregularities becomes significantly small. Thus, in the case where the shape and dimensions of irregularities on a surface of the transparent substrate 2 (pre-pit area or pre-groove area 10) are equal to each other depending on a difference in method for forming a recording film, the diffraction intensity of the reflection light beam from the organic dye recording film at the time of laser light irradiation is degraded more significantly than the diffraction intensity of the reflection light beam from the phase change recording film. As a result, in the case where the shape and dimensions of irregularities on the surface of the transparent substrate 2 (pre-pit area or pre-groove area 10) are equal to each other, as compared with use of the phase change recording film, use of the conventional organic dye recording film is disadvantageously featured in that: 1) a degree of modulation of a light reproduction signal from the pre-pit area is small, and signal reproduction reliability from the pre-pit area is poor; 2) a sufficiently large track shift detecting signal is hardly obtained in accordance with a pushpull technique from the pre-groove area; and 3) a sufficient large wobble detecting signal is hardly obtained in the case where wobbling occurs in the pre-groove area. In addition, in a DVD-R disk, specific information such as address information is recorded in a small irregular (pit) shape in a land area, and thus, a width Wl of the land area 12 is larger than a width Wg of the pre-pit area or pre-groove area 10 (Wg Wl). Chapter 3: Description of Characteristics of Organic Dye Recording Film in the Present Embodiment 3-1) Problem(s) relevant to achievement of high density in write-once type recording film (DVD-R) using conventional organic dye material As has been described in "2-1) Difference in recording principle/recording film structure and difference in basic concept relating to generation of reproducing signal", a general principle of recording of a current DVD-R and CD-R, which is a write-once type information storage medium using a conventional organic dye material includes "local plastic deformation of transparent substrate 2-2" or "local thermal decomposition or "gasification" in recording layer 3-2". FIGS. 6A and 6B each show a plastic deformation state of a specific transparent substrate 2-2 at a position of a recording mark 9 in a write-once type information storage medium using a conventional organic dye material. There exist two types of typical plastic deformation states. There are two cases, i.e., a case in which, as shown in FIG. 6A, a depth of a bottom surface 14 of a pre-groove area at the position of the recording mark 9 (an amount of step relevant to an adjacent land area 12) is different from a depth of a bottom surface of a pre-groove area 11 in an unrecorded area (in the example shown in FIG. 6A, the depth of the bottom surface 14 in the pre-groove area at the position of the recording mark 9 is shallower than that in the unrecorded area); and a case in which, as shown in FIG. 6B, a bottom surface 14 in a pre-groove area at the position of the recording mark 9 is distorted and is slightly curved (the flatness of the bottom surface 14 is distorted: In the example shown in FIG. 6B, the bottom surface 14 in the pre-groove area at the position of the recording mark 9 is slightly curved toward the lower side). Both of these cases are featured in that a plastic deformation range of the transparent substrate 2-2 at the position of the recording mark 9 covers a wide range. In the current DVD-R disk which is a conventional technique, a track pitch is 0.74 jam, and a channel bit length is 0.133 )im. In the case of a large value of this degree, even if the plastic deformation range of the transparent substrate 2-2 at the position of the recording mark 9 covers a wide range, comparatively stable recording and reproducing processes can be carried out. However, if the track pitch is narrower than 0.74 fj,m described above, the plastic deformation range of the transparent substrate 2-2 at the position of the recording mark 9 covers a wide range, and thus, the adjacent tracks are adversely affected, and the recording mark 9 of the existing adjacent track is substantially erased (cannot be reproduced) due to a "cross-write" or overwrite in which the recording mark 9 widens to the adjacent tracks. In addition, in a direction (circumferential direction) along the tracks, if the channel bit length is narrower than 0.133 (im, there occurs a problem that inter-code interference appears; an error rate at the time of reproduction significantly increases; and the reliability of reproduction is lowered. 3-2) Description of basic characteristics common to organic dye recording film in the present embodiment 3-2-A] Range requiring application of technique according to the present embodiment As shown in FIGS. 6A and 6B, in a conventional write-once type information storage medium including plastic deformation of the transparent substrate 2-2 or local thermal decomposition or gasification phenomenon in the recording film 3-2, a description will be given below with respect to what degree of track pitch is narrowed when an adverse affect appears or what degree of channel pit length is narrowed when an adverse effect appears and a result obtained after technical discussion has been carried out with respect to a reason for such an adverse effect. A range in which an adverse effect starts appearing in the case of utilizing the conventional principle of recording indicates a range (suitable for the achievement of high density) in which advantageous effect is attained due to a novel principle of recording shown in the present embodiment. 1) Condition of thickness Dg of recording layer 3-2 When an attempt is made to carry out thermal analysis in order to theoretically identify a lower limit value of an allowable channel bit length or a lower limit value of allowable track pitch, a range of the thickness Dg of a recording layer 3-2 which can be substantially thermally analyzed becomes important. In a conventional write-once type information storage medium (CD-R or DVD-R) including plastic deformation of the transparent substrate 2-2 as shown in FIGS. 6A and 6B, with respect to a change of light reflection amount in the case where an information reproduction focusing spot is provided in the recording mark 8 and in the case where the spot is in an unrecorded area of the recording layer 3-2, the largest factor is "an interference effect due to a difference in optical distance in the recording mark 9 and in unrecorded area". In addition, a difference in its optical difference is mainly caused by "a change of the thickness Dg of a physical recording layer 3-2 due to plastic deformation of the transparent substrate 2-2 (a physical distance from an interface between the transparent substrate 2-2 and the recording layer 3-2 to an interface between the recording layer 3-2 and a light reflection layer 4-2) and "a change of refractive index n32 °f the recording layer 3-2 in the recording mark 9". Therefore, in order to obtain a sufficient reproduction signal (change of light reflection amount) between the recording mark 9 and the unrecorded area, when a wavelength in vacuum of laser light beam is defined as X, it is necessary for the value of the thickness 3-2 in the unrecorded area has a size to some extent as compared with X/n32. If not, a difference (phase difference) in optical distance between the recording mark 9 and the unrecorded area does not appear, and light interference effect becomes small. In reality, a minimum condition: Dg A./8n32 (1) must be met, and desirably, a condition that: Dg X/4n32 (2) At a time point of current discussion, the vicinity of A, = 405 nm is assumed. A value of refractive index n2 °f an organic dye recording material at 405 nm ranges from 1.3 to 2.0. Therefore, as a result of substituting n2 = 2.0 in formula (1), it is conditionally mandatory that a value of the thickness Dg of the recording layer 3-2 is: Dg 25 nm (3) Here, discussion is made with respect to a condition when an organic dye recording layer of a conventional write-once type information storage medium (CD-R or DVD-R) including plastic deformation of the transparent substrate 2-2 has been associated with a light beam of 405 nm. As described later, in the present embodiment, although a description is given with respect to a case in which plastic deformation of the transparent substrate 2-2 does not occur and a change of an absorption coefficient k2 is a main factor of a principle of recording, it is necessary to carry out track shift detection by using a DPD (Differential Phase Detection) technique from the recording mark 9, and thus, in reality, the change of the refractive index n32 is caused in the recording mark 9. Therefore, the condition for formula (3) becomes a condition, which should be met, in the present embodiment in which plastic deformation of the transparent substrate 2-2 does not occur. From another point of view as well, the range of the thickness Dg can be specified. In the case of a phase change recording film shown in FIG. 5A, when a refractive index of the transparent substrate is r\2i, a step amount between a pre-pit area and a land area is X/(8n2i) when the largest track shift detection signal is obtained by using a push-pull technique. However, in the case of an organic dye recording film shown in FIG. 5B, as described previously, the shape on an interface between the recording layer 3-2 and the light reflection layer 4-2 becomes blunt, and a step amount becomes small. Thus, it is necessary to increase a step amount between a pre-pit area and a land area on the transparent substrate 2-2 more significantly than X/(8n22) For example, the refractive index at 405 nm in the case where polycarbonate has been used as a material for the transparent substrate 2-2 is n22 1-62, and thus, it is necessary to increase a step amount between the pre-pit area and the land area more significantly than 31 nm. In the case of using a spin coating technique, if the thickness Dg of the recording layer 3-2 in the pre-groove area is greater than a step amount between the pre-pit area and the land area on the transparent substrate 2-2, there is a danger that thickness Dl of the recording layer 3-2 in a land area 12 is eliminated. Therefore, from the above described discussion result, it is necessary to meet a condition that: Dg ^ 31 nm (4) The condition for formula (4) is also a condition, which should be met in the present embodiment in which plastic deformation of the transparent substrate 2-2 does not occur. Although conditions for the lower limit values have been shown in formulas (3) and (4), the value Dg = 60 nm obtained by substituting n2 = 1.8 for an equal sign portion in formula (2) has been utilized as the thickness Dg of the recording layer 3-2 used for thermal analysis. Then, assuming polycarbonate used as a standard material of the transparent substrate 2-2, 150°C which is a glass transition temperature of polycarbonate has been set as an estimate value of a thermal deformation temperature at the side of the transparent substrate 2-2. For discussion using thermal analysis, a value of k32 = 0.1 to 0.2 has been assumed as a value of an absorption coefficient of the organic dye recording film 3-2 at 405 nm. Further, discussion has been made with respect to a case in which an NA value of a focusing objective lens and an incident light intensity distribution when an objective lens is passed is NA = 60 and H format ((D1):NA = 0.65 in FIG. 1) and B format ((D2):NA = 0.85 in FIG. 1) which is assumed condition in a conventional DVD-R format. 2) Condition for lower limit value of channel bit length A check has been made for a lengthwise change in a direction along a track of an area reaching a thermal deformation temperature at the side of a transparent substrate 2-2 which comes into contact with a recording layer 3-2 when recording power has been changed. Discussion has been made with respect to a lower limit value of an allowable channel bit length considering a window margin at the time of reproduction. As a result, if the channel bit length is slightly lower than 105 nm, it is considered that a lengthwise change in a direction along a track in an area which reaches the thermal deformation temperature at the side of the transparent substrate 2-2 occurs according to the slight change of recording power, and a sufficient window margin cannot be obtained. On discussion of thermal analysis, an analogous tendency is shown in the case where the NA value is any one of 0.60, 0.65, and 0.85. Although a focusing spot size is changed by changing the NA value, a possibility cause is believed to be that a thermal spreading range is wide (a gradient of a temperature distribution at the side of the transparent substrate 2-2 which comes into contact with the recording layer 3-2) is comparatively gentle). In the above thermal analysis, the temperature distribution at the side of the transparent substrate 2-2 which comes into contact with the recording layer 3-2 is discussed, and thus, an effect of the thickness Dg of the recording layer 3-2 does not appear. Further, in the case where a shape change of the transparent substrate 3-3 shown in FIGS. 6A and 6B occurs, a boundary position of a substrate deformation area blurs (is ambiguous), and thus, a window margin is lowered more significantly. When a sectional shape of an area in which the recording mark 9 is formed is observed by an electron microscope, it is believed that a blurring amount of the boundary position of the substrate deformation area increases as the value of the thickness Dg of the recording layer 3-2 increases. With respect to the effect of the thermal deformation area length due to the above recording power change, in consideration of the blurring of the boundary position of this substrate deformation area, it is considered necessary that the lower limit value of the channel bit length allowed for allocation of a sufficient window margin is in order of two times of the thickness Dg of the recording layer 3-2, and it is desirable that the lower limit value is greater than 120 nm. In the foregoing, a description has been principally given with respect to discussion using thermal analysis in the case where thermal deformation of the transparent substrate 2-2 occurs. There also exists a case in which plastic deformation of the transparent substrate 2-2 is very small as another orinciple of recording (mechanism of forming the recording mark 9) in a conventional write-once type information storage medium (CD-R or DVD-R) and thermal deformation or gasification (evaporation) of the organic dye recording material in the recording layer 3-2 mainly occurs. Thus, an additional description rfill be given with respect to such a case. Although the gasification (evaporation) temperature of the organic dye recording material is different depending on the type of the organic dye material, in general, the temperature ranges 220°C to 370°C, and a thermal decomposition temperature is lower than this range. Although a glass transition temperature 150°C of a polycarbonate resin has been presumed as an arrival temperature at the time of substrate deformation in the above discussion, a temperature difference between 150°C and 220°C is small, and, when the transparent substrate 2-2 reaches 150°C, the inside of the recording layer 3-2 exceeds 220°C. Therefore, although there exists an exception depending on the type of the organic recording material, even in the case where plastic deformation of the transparent substrate 2-2 is very small and thermal decomposition or gasification (evaporation) of the organic dye recording material in the recording layer mainly occurs, there is obtained a result which is substantially identical to the above discussion result. When the discussion result relating to the above channel bit length is summarized, in the conventional write-once type information storage medium (CD-R or DVD-R) including plastic deformation of the transparent substrate 2-2, it is considered that, when a channel bit length is narrower than 120 nm, the lowering of a window margin occurs, and further, if the length is smaller than 105 nm, stable reproduction becomes difficult. That is, when the channel bit is smaller than 120 nm (105 nm), advantageous effect is attained by using a novel principle of recording shown in the present embodiment. 3) Condition for lower limit value of track pitches When a recording layer 3-2 is exposed at recording power, energy is absorbed in the recording layer 3-2, and a high temperature is obtained. In a conventional write-once type information storage medium (CD-R or DVD-R), it is necessary to absorb energy in the recording layer 3-2 until the transparent substrate 3-2 has reached a thermal deformation temperature. A temperature at which a structural change of the organic dye recording material occurs in the recording layer 3-2 and a value of a refractive index r\2 or an absorption coefficient k^2 starts its change is much lower than an arrival temperature for the transparent substrate 2-2 to start thermal deformation. Therefore, the value of the refractive index 1132 or absorption coefficient k^2 changes in a comparatively wide range in the recording layer 3-2 at the periphery of a recording mark 9, which is thermal deformed at the side of the transparent substrate 2-2, and this change seems to cause "cross-write" or "cross-erase" for the adjacent tracks. It is possible to set a lower limit value of track pitch in which "cross-write" or "crosserase" does not occur with the width of an area which reaches a temperature which changes the refractive index n^2 or absorption coefficient k^2 i-n the recording layer 3-2 when the transparent substrate 2-2 exceeds a thermal deformation temperature. From the above point of view, it is considered that "crosswrite" or "cross-erase" occurs in location in which the track pitch is equal to or smaller than 500 ran. Further, in consideration of an effect of warping or inclination of an information storage medium or a change of recording power (recording power margin), it can be concluded difficult to set the track pitch to 600 nm or less in the conventional write-once type information storage medium (CD-R or DVD-R) in which energy is absorbed in the recording layer 3-2 until the transparent substrate 2-2 has reached a thermal deformation temperature. As described above, even if the NA value is changed from 0.60, 0.65, and then, to 0.85, substantially similar tendency is shown because the gradient of the temperature distribution in the peripheral recording layer 3-2 when the transparent substrate 2-2 has reached a thermal deformation temperature at a center part is comparatively gentle, and the thermal spread range is wide. In the case where plastic deformation of the transparent substrate 2-2 is very small and thermal decomposition or gasification (evaporation) of the organic dye recording material in the recording layer 3-2 mainly occurs as another principle of recording (mechanism of forming the recording mark 9) in the conventional write-once type information storage medium (CD-R or DVD-R), as has been described in the section "(2) Condition for lower limit value of channel bit", the value of track pitch at which "cross-write" or "cross-erase" starts is obtained as a substantially analogous result. For the above described reason, advantageous effect is attained by using a novel principle of recording shown in the present embodiment when the track pitch is set to 600 nm (500 nm) or lower. 3-2-B] Basic characteristics common to organic dye recording material in the invention As described above, in the case where plastic deformation of the transparent substrate 2-2 is very small and thermal decomposition or gasification (evaporation) of the organic dye recording material in the recording layer 3-2 mainly occurs as another principle of recording (mechanism of forming the recording mark 9) in the conventional write-once type information storage medium (CD-R or DVD-R), there occurs a problem that a channel bit length or track pitches cannot be narrowed because the inside of the recording layer 3-2 or a surface of the transparent substrate 2-2 reaches a high temperature at the time of forming the recording mark 9. In order to solve the above described problem, the present embodiment is primarily featured in "inventive organic dye material" in which "a local optical characteristic change in the recording layer 3-2, which occurs at a comparatively low temperature, is a principle of recording" and "setting environment (recording film structure or shape) in which the above principle of recording easily occurs without causing a substrate deformation and gasification (evaporation) in the recording layer 3-2. Specific characteristics of the present embodiment can be listed below. a] Optical characteristic changing method inside of recording layer 3-2 Chromogenic characteristic change Change of light absorption sectional area due to qualitative change of light emitting area 8 (FIG. 3) or change of molar molecule light absorption coefficient The light emitting area 8 is partially destroyed or the size of the light emitting area 8 changes, whereby a substantial light absorption sectional area changes. In this manner, an amplitude (absorbance) at a position of changes in the recording mark 9 while a profile (characteristics) of light absorption spectra (FIG. 4) itself is maintained. Change of electronic structure (electron orbit) relevant to electrons which contribute to a chromogenic phenomenon Change of light absorption spectra (FIG. 4) based on discoloring action due to cutting of local electron orbit (dissociation of local molecular bonding) or change of dimensions or structure of light emitting area 8 (FIG. 3) Intra-molecular (inter-molecular) change of orientation or array Optical characteristic change based on orientation change in azo metal complex shown in FIG. 3, for example Molecular structure change in molecule For example, discussion is made with respect to an organic dye material which causes either of dissociation between anion portion and cation portion, thermal decomposition of either of anion portion and cation portion, and a tar phenomenon that a molecular structure itself is destroyed, and carbon atoms are precipitated (denaturing to black coal tar). As a result, the refractive index n^2 or absorption coefficient k^2 in the recording mark 9 is changed with respect to an unrecorded area, enabling optical reproduction. P] Setting recording film structure or shape, making it easy to stably cause an optical characteristic change of [a] above: The specific contents relating to this technique will be described in detail in the section "3-2-C] Ideal recording film structure which makes it easy to cause a principle of recording shown in the present embodiment" and subsequent. y] Recording power is reduced in order to form recording mark in a state in which inside of recording layer or transparent substrate surface is comparatively low at temperature The optical characteristic change shown in [a] above occurs at a temperature lower than a deformation temperature of the transparent substrate 2-2 or a gasification (evaporation) temperature in the recording layer 3-2. Thus, the exposure amount (recording power) at the time of recording is reduced to prevent the deformation temperature from being exceeded on the surface of the transparent substrate 2-2 or the gasification (evaporation) temperature from being exceeded in the recording layer 3-2. The contents will be described later in detail in the section "3-3) Recording characteristics common to organic dye recording layer in the present embodiment". In addition, in contrast, it becomes possible to determine whether or not the optical characteristic change shown in [a] above occurs by checking a value of the optimal power at the time of recording. 8] Electron structure in a light emitting area is stabilized, and structural decomposition relevant to ultraviolet ray or reproduction light irradiation is hardly generated When ultraviolet ray is irradiated to the recording layer 3-2 or reproduction light is irradiated to the recording layer 3-2 at the time of reproduction, a temperature size in the recording layer 3-2 occurs. There is a request for a seemingly contradictory performance that characteristic degradation relevant to such a temperature rise is prevented and recording is carried out at a temperature lower than a substrate deformation temperature or a gasification (evaporation) temperature in the recording layer 3-2. In the present embodiment, the above described seemingly contradictory performance is ensured by "stabilizing an electron structure in a light emitting area". The specific technical contents will be described in "Chapter 4 Specific Description of Embodiments of Organic Dye Recording Film in the Present Embodiment". e] Reliability of reproduction information is improved for a case in which reproduction signal degradation due to ultraviolet ray or reproduction light irradiation occurs In the present embodiment, although a technical contrivance is made for "stabilizing an electron structure in a light emitting area", the reliability of the recording mark 9 formed in a principle of recording shown in the present embodiment may be principally lowered as compared with a local cavity in the recording layer 3-2 generated due to plastic deformation or gasification (evaporation) of the surface of the transparent substrate 2-2. As countermeasures against it, in the present embodiment, advantageous effect that the high density and the reliability of recording information are achieved at the same time in combination with strong error correction capability (novel ECC block structure), as described later in "Chapter 7: Description of H Format" and "Chapter 8: Description of B Format". Further, in the present embodiment, PRML (Partial Response Maximum Likelihood) technique is employed as a reproduction method, as described in the section "4-2 Description of reproducing circuit in the present embodiment", the high density and the reliability of recording information are achieved at the same time in combination with an error correction technique at the time of ML demodulation. Among the specific characteristics of the above described present embodiment, a description has been given with respect to the fact that items [a] to [y] are the contents of technical contrivance newly devised in the present embodiment in order to achieve "narrow track pitch" and "narrow channel bit length". In addition, "narrow channel bit length" causes the achievement of "reduction of minimum recording mark length". The meanings (objects) of the present embodiment relating to the remaining items [8] and [e] will be described in detail. At the time of reproduction in the H format in the present embodiment, a passage speed (line speed) of a focusing spot of light passing through the recording layer 3-2 is set to 6.61 m/s, and the line speed in the B format is set in the range of 5.0 m/s to 10.2 m/s. In any case, the line speed at the time of reproduction in the present embodiment is equal to or greater than 5 m/s. As shown in FIG. 31, a start position of a data lead-in area DTLDI in the H format is 47.6 mm in diameter. In view of the B format as well, user data is recorded in location equal to or greater than 45 mm in diameter. An inner periphery of 45 mm in diameter is 0.141 m, and thus, the rotation frequency of an information storage medium when this position is reproduced at a line speed of 5 m/s is obtained as 35.4 rotations/s. Video image information such as TV program is provided as one of the methods utilizing a write-once type information storing medium according to the present embodiment. For example, when a user presses "pause (temporary stop) button" at the reproduction of the user's recorded video image, a reproduction focusing spot stays on a track of its paused position. When the spot stops on the track of the paused position, the user can start reproduction at the paused position immediately after a "reproduction start button" has been pressed. For example, after the user has pressed a "pause (temporary stop) button", in the case where a customer visits the user's home immediately after the user has gone to toilet, there is a case in which the pause button is left to have been pressed for one hour while the user meets the customer. The write-once type information storage medium makes 35.4 x 60 x 60 ^ 130,000 rotations for one hour, and the focusing spot traces on the same track during this period (130,000 repetitive playbacks). If the recording layer 3-2 is degraded due to repetitive playback and video image information cannot be reproduced after this period, the user coming back one hour later cannot see any portion of video image, and thus, gets angry, and in the worst case, there is a danger that the problem may be taken to court. Therefore, a minimum condition that, if the recorded video image information is not destroyed even if such a pausing is left for one hour or longer (even if continuous playback in the same track occurs), no video image data is destroyed, requires to guarantee that at least 100,000 repetitive playback occurs, no reproduction degradation occurs. There is a rare case in which a user repeats one-hour pausing (repetitive playback) 10 times with respect to the same location in a general use condition. Therefore, when it is guaranteed that the write-once type information storage medium according to the present embodiment desirably makes 1,000,000 repetitive playbacks, no problem occurs with use by the general user, and it is considered sufficient to set to about 1,000,000 times the upper limit value of the repetitive playback count as long as the recording layer 3-2 is not degraded. If the upper limit value of the repetitive playback count is set to a value which significantly exceeds 1,000,000 times, there occurs inconvenience that "recording sensitivity is lowered" or "medium price increases". In the case where the upper limit value of the above repetitive reproduction count is guaranteed, a reproduction power value becomes an important factor. In the present embodiment, recording power is defined in a range set in formulas (8) to (13). It is said that a semiconductor laser beam is featured in that continuous light irradiation is not stable in a value equal to or smaller than 1/80 of the maximum use power. Because the power, which is 1/80 of the maximum use power, is in location in which light irradiation is just started (mode initiation is started), mode hopping is likely to occur. Therefore, at this light irradiation power, the light reflected in the light reflection layer 4-2 of the information storage medium comes back to a semiconductor laser light source, there occurs a "return light noise" featured in that the light emission amount always changes. Accordingly, in the present embodiment, the values of the reproduction power is set below around the value which is 1/80 of the value described at the right side of formula (12) or formula (13): [Optical reproduction power] 0.19 x (0.65/NA)2 x (V/6.6) (B-l) [Optical reproduction power] 0.19 x (0.65/NA)2 x (V/6.6)1-2 (B-2) In addition, the value of the optimal reproduction power is restricted by a dynamic range of a power monitoring optical detector. Although not shown in an information recording/reproducing unit 141 of FIG. 11, a recording/reproducing optical head exists. This optical head incorporates an optical detector which monitors a light emission amount of a semiconductor laser light source. In the present embodiment, in order to improve light irradiation precision of the reproduction power at the time of reproduction, this optical detector detects a light emission amount and applies a feedback to an amount of a current to be supplied to the semiconductor laser light source at the time of light irradiation. In order to lower a price of the optical head, it is necessary to use a very inexpensive optical detector. A commercially available, inexpensive optical detector is often molded with a resin (an optical detecting unit is surrounded). As disclosed in "Chapter 0: Description of Relationship between Use Wavelength and the Present Embodiment", 530 nm or less (in particular, 455 nm or less) is used as a light source wavelength in the present embodiment. In the case of this wavelength area, a resin with which the optical detecting unit is molded (mainly, epoxy resin) causes such a degradation that occurs when ultraviolet ray has been irradiated if the wavelength light is irradiated (such as dark yellow discoloring or occurrence of cracks (fine white stripes)) and the optical detection characteristics are impaired. In particular, in the case of the write-once type information storage medium shown in the present embodiment, a mold resin degradation is likely to occur because the storage medium has a pre-groove area 11 as shown in FIGS. 8A, 8B and 8C. As a focus blurring detection system of an optical head, in order to remove adverse effect due to the diffraction light from this pre-groove area 11, there is most often employed a "knife-edge technique" of allocating an optical detector at an image forming position relevant to the information storage medium (image forming magnification M is in order of 3 times to 10 times). When the optical detector is arranged at the image forming position, high optical density is irradiated onto a mold resin because light beams are focused on the optical detector, and resin degradation due to this light irradiation is likely to occur. This mold resin characteristic degradation mainly occurs due to a photon mode (optical action), and however, it is possible to predict an upper limit value of an allowable irradiation amount in comparison with a light emission amount in a thermal mode (thermal excitation). Assuming the worst case, let us assume an optical system in which an optical detector is arranged at an image forming position as an optical head. From the contents described in "(1) Condition for thickness Dg of recording layer 3-2" in "3-2-A] Range requiring application of technique according to the present embodiment", when an optimal characteristic change (thermal mode) occurs in the recording layer 3-2 at the time of recording in the present embodiment, it is considered that a temperature temporarily rises in the range of 80°C to 150°C in the recording layer 3-2. In view of a room temperature of about 15°C, a temperature difference ranges from 65°C to 135°C. Pulse light emissions occur at the time of recording, and continuous light emissions occur at the time of reproduction. At the time of reproduction, the temperature rises in the recording layer 3-2 and a temperature difference occurs. When an image forming magnification of a detecting system in the optical head is M, the optical density of the detected light focused on the optical detector is obtained as 1/M2 of the optical density of convergence light irradiated on the recording layer 3-2, and thus, a temperature rise amount on the optical detector at the time of reproduction is obtained as ATreaci/M2 which is a rough estimate. In view of the fact that an upper limit value of optical density, which can be irradiated on the optical detector, is converted by the temperature rise amount, it is considered that the upper limit value is in order of iyi2 1°C. The image foaming magnification of the detecting system in the optical head M is in order of 3 times to 10 times in general, if the magnification M2 =. tentatively estimated, it is necessary to set reproduction power so as to obtain: ATread/ATwrite = 20 (B-3) Assuming that a duty ratio of recording pulses at the time of recording is estimated as 50%, the following is required: [Optimal reproduction power] [Optimal recording power]710 (B-4) Therefore, in view of formulas (8) to (13) described later and the above formula (B-4), optimal reproduction power is assigned as follows: [Optimal reproduction power] [Optimal reproduction power] [Optimal reproduction power] [Optimal reproduction power] [Optimal reproduction power] [Optimal reproduction power] (Refer to "3-2-E] Basic characteristics relating to thickness distribution of recording layer in the present embodiment for definition of parameters".) For example, when NA = 0.65 and V = 6.6 m/s, the following is obtained: [Optimal reproduction power] [Optimal reproduction power] [Optimal reproduction power] In reality, the optical detector is fixed as compared with the fact the information storage medium rotates and relatively moves, and thus, in consideration of this fact, it is necessary to further set the optimal reproduction power to be in order of 1/3 or less of the value obtained in the above formula. In the information recording/reproducing apparatus according to the present embodiment, a value of the reproduction power is set to 0.4 mW. 3-2-C] Ideal recording film structure in which a principle of recording shown in the present embodiment is easily generated A description will be given with respect to a method for "setting an environment" (recording film structure or shape) in which the above principle of recording is easily generated in the present embodiment. As an environment in which an optical characteristic change inside of the above described recording layer 3-2 is likely to occur, the present embodiment is featured in that a technical contrivance is carried out in recording film structure or shape such as: "in an area for forming the recording mark 9, a critical temperature at which an optical characteristic change is likely to occur is exceeded, and at a center part of the recording mark 9, a gasification (evaporation) temperature is not exceeded, and a surface of a transparent substrate 2-2 in the vicinity of the center part of the recording mark 9 does not exceed a thermal temperature". The specific contents relating to the above description will be described with reference to FIGS. 7A, 7B and 7C. In FIGS. 7A, 7B and 1C, the open (blank) arrow indicates an optical path of an irradiation laser light beam 7, and the arrow of the dashed line indicates a thermal flow. A recording film structure shown in FIG. 7A indicates an environment in which an optical characteristic change inside of a recording layer 3-2 corresponding to the present embodiment is most likely to occur. That is, in FIG. 7A, the recording layer 3-2 consisting of an organic dye recording material has uniform thickness anywhere in the range shown in formula (3) or formula (4) (where the thickness is sufficiently large), and receives irradiation of the laser light beam 7 in a direction vertical to the recording layer 3-2. As described in detail in "6-1) light reflection layer (material and thickness)", a silver alloy is used as a material for a light reflection layer 4-2 in the present embodiment. A material including a metal with high light reflection factor, in general, has high thermal conductivity and heat radiation characteristics without being limited to the silver alloy. Therefore, although a temperature of the recording layer 3-2 is risen by absorbing the energy of the irradiated laser light beam 7, a heat is radiated toward the light reflection layer 4-2 having heat radiation characteristics. Although a recording film shown in FIG. 7A is formed anywhere in a uniform shape, a comparatively uniform temperature rise occurs inside of the recording layer 3-2, and a temperature difference at points a, P, and y at the center part is comparatively small. Therefore, when the recording mark 9 is formed, when a critical temperature at which an optical characteristic change at the points a and P occurs is exceeded, a gasification (evaporation) temperature is not exceeded at the point a of the center part; and a surface of a transparent substrate (not shown) which exists at a position which is the closest to the point a of the center part does not exceed a thermal deformation temperature. In comparison, as shown in FIG. 7B, a step is provided partly of the recording film 3-2. At the points 5 and e, the radiation of the laser light beam 7 is subjected in a direction oblique to a direction in which the recording layer 3-2 is arrayed, and thus, an irradiation amount of the laser light beam 7 per a unit area is relatively lowered as compared with the point cc of the center part. As a result, a temperature rise amount in the recording layer 3-2 at the points 8 and e is lowered. At the points 8 and E as well, thermal radiation toward the light reflection layer 4-2 occurs, and thus, the arrival temperature at the points 8 and s is sufficiently lowered as compared with the point a of the center part. Therefore, a heat flows from the point P to the point a and a heat flows from the point a to the point P, and thus, a temperature difference at the points P and y relevant to the point a of the center part becomes very small. At the time of recording, a temperature rise amount at the points P and y is low, and a critical temperature at which an optical characteristic change occurs is hardly exceeded at the points p and a. As countermeasures against it, in order to produce an optical characteristic change occurs at the points P and y (in order to produce a critical temperature or more), it is necessary to increase an exposure amount (recording power) of the laser light beam 7. In the recording film structure shown in FIG. 7B, a temperature difference at the point a of the center part relevant to the points P and y is very large. Thus, when a current temperature has risen at a temperature at which an optical characteristic change occurs at the points P and y, a gasification (evaporation) temperature is exceeded at the point a of the center part or the surface of a transparent substrate (not shown) in the vicinity of the point a of the center part hardly exceeds a thermal deformation temperature. In addition, even if the surface of the recording layer 3-2 at the side at which irradiation of the laser light beam 7 is subjected is vertical to the irradiation direction of the laser light beam 7 anywhere, in the case where the thickness of the recording layer 3-2 changes depending on a location, there is provided a structure in which an optical characteristic change inside of the recording layer 3-2 according to the present embodiment hardly occurs. For example, as shown in FIG. 7C, let us consider a case in which the thickness Dl of a peripheral part is significantly small with respect to the thickness Dg of the recording layer 3-2 at the point a of the center part (for example, formula (2) or formula (4) is not satisfied). Even at the point a of the center part, although heat radiation toward the light reflection layer 4-2 occurs, the thickness Dg of the recording layer 3-2 is sufficiently large, thus making it possible to achieve heat accumulation and to achieve a high temperature. In comparison, at the points 2, and rat which the thickness Dl is significantly small, a heat is radiated toward the light reflection layer 4-2 without carrying out heat accumulation, and thus, a temperature rise amount is small. As a result, heat radiation toward points p, 8, and £, in order and heat radiation toward points y, e, and r\| in order occurs as well as heat radiation toward the light reflection layer 4-2, and thus, as in FIG. 7B, a temperature difference at the point a of the center part relevant to points P and y becomes very large. When an exposure amount of the laser light beam 7 (recording power) is increased in order to produce an optical characteristic change at the points P and y (in order to produce a critical temperature or more), the gasification (evaporation) temperature at the point a of the center part is exceeded or the surface of the transparent substrate (not shown) in the vicinity of the point a of the center part easily exceeds a thermal deformation temperature. Based on the contents described above, referring to FIGS. 8A, 8B and 8C, a description will be given with respect to: the contents of a technical contrivance in the present embodiment relating to the pre-groove shape/dimensions for providing "setting of environment (structure or shape of a recording film)" in which a principle of recording according to the present embodiment is likely to occur; and the contents of a technical contrivance in the present embodiment relating to a thickness distribution of the recording layer. FIG. 8A shows a recording film structure in a conventional write-once type information storage medium such as CD-R or DVD-R; and FIGS. 8B and 8C each show a recording film structure in the present embodiment. In the invention, as shown in FIGS. 8A, 8B and 8C, a recording mark 9 is formed in a pre-groove area 11. 3-2-D] Basic characteristics relating to pregroove shape/dimensions in the present embodiment As shown in FIG. 8A, there have been many cases in which a pre-groove area 11 is formed in a "V-groove" shape in a conventional write-once type information storage medium such as CD-R or DVD-R. In the case of this structure, as described in FIG. 7B, the energy absorption efficiency of the laser light beam 7 is low, and the temperature distribution non-uniformity in the recording layer 3-2 becomes very large. The present embodiment is featured in that, in order to make close to an ideal state of FIG. 7A, a planar shape orthogonal to a traveling direction of the incident laser light beam 7 is provided in the pre-groove area 11 at the side of at least the "transparent substrate 2-2". As described with reference to FIG. 7A, it is desirable that this planar area be as wide as possible. Therefore, the present embodiment is secondarily featured in that the planar area is provided in the pre-groove area 11 and the width Wg of the pre-groove area 11 is wider than the width Wl of a land area (Wg Wl). In this description, the width Wg of the pregroove area and the width Wl of the land area are defined as their respective widths at a position at which there crosses a plane having an intermediate height between a height at a planar position of the pre-groove area and a height at a position at which the land area becomes the highest and an oblique surface in the pre-groove. A discussion has been made using thermal analysis, data has been recorded in a write-once type information storage medium actually produced as a prototype, substrate deformation observation due to a sectional SEM (scanning type electronic microscope) image at the position of the recording mark 9 has been made, and observation of the presence or absence of a cavity generated due to gasification (evaporation) in the recording layer 3-2 has been repeated. As a result, it is found that advantageous effect is attained by widening the width Wg of the pre-groove area more significantly than the width Wl of the land area. Further, a ratio of the pre-groove area width Wg and the land area width Wl is Wg:Wl = 6:4, and desirably, is greater than Wg:Wl = 7:3, whereby it is considered that a local optical characteristic change in the recording layer 3-2 is likely to occur while the change is more stable at the time of recording. As described above, when a difference between the pre-groove area width Wg and the land area width Wl is increased, a flat surface is eliminated from the top of the land area 12, as shown in FIG. 8C. In the conventional DVDR disk, a pre-pit (land pre-pit: not shown) is formed in the land area 12, and a format for recording address information or the like in advance is realized here. Therefore, it is conditionally mandatory to form a flat area in the land area 12. As a result, there has been a case in which the pre-groove area 11 is formed in the "V-groove" shape. In addition, in the conventional CD-R disk, a wobble signal has been recorded in the pre-groove area 11 by means of frequency modulation. In a frequency modulation system in the conventional CD-R disk, slot gaps (a detailed description of each format is given in detail) are not constant, and phase adjustment at the time of wobble signal detection (PLL: synchronization of PLL (Phase Lock Loop)) has been comparatively difficult. Thus, a wall face of the pre-groove area 11 is concentrated (made close to the V-groove) in the vicinity of a center at which the intensity of a reproducing focusing spot is the highest and a wobble amplitude amount is increased, whereby the wobble signal detection precision has been guaranteed. As shown in FIGS. 8B and 8C, after the flat area in the pre-groove area 11 in the present embodiment has been widened, when the oblique surface of the pre-groove area 11 is shifted to the outside relatively than a center position of the reproducing focusing spot, a wobble detection signal is hardly obtained. The present embodiment is featured in that the width Wg of the pre-groove area described above is widened and the H format utilizing PSK (Phase Shift Keying) in which slot gaps at wobble detection is always fixedly maintained or the B format utilizing FSK (Frequency Shift Keying) or STW (Saw Tooth Wobble) are combined, whereby stable recording characteristics are guaranteed (suitable to high speed recording or layering) at low recording power and stable wobble signal detection characteristics are guaranteed. In particular, in the H format, in addition to the above combination, "a ratio of a wobble modulation is lowered more significantly than that of a non-modulation area", thereby facilitating synchronization at the time of wobble signal detection more significantly, and further, stabilizing wobble signal detection characteristics more significantly. 3-2-E] Basic characteristics relating to thickness distribution of recording layer 3-2 in the present embodiment In the present description, as shown in FIGS. 8B and 8C, the thickness in a portion at which the recording layer 3-2 in the land area 12 is the thickest is defined as recording layer thickness Dl in the land area 12; and a portion at which the recording layer 3-2 in the pre-groove area 11 is the thickest is defined as recording layer thickness Dg in the pre-groove area. As has been described with reference to FIG. 1C, the recording layer thickness Dl in the land area is relatively increased, whereby a local optical characteristic change in the recording layer is stably likely to occur at the time of recording. In the same manner as that described above, a discussion has been made using thermal analysis, data has been recorded in a write-once type information storage medium actually produced as a prototype, substrate deformation observation and observation of the presence or absence of a cavity generated due to gasification (evaporation) in the recording layer 3-2 by a sectional SEM (scanning type electronic microscope) image at the position of the recording mark 9 have been made. As a result, it has been found necessary to set a ratio between the recording layer thickness Dg in the pre-groove area and the recording layer thickness Dl in the land area to be equal to or smaller than Dg:Dl = 4:1. Further, Dg:Dl = 3:1 is set, and desirably, Dg:Dl = 2:1 is set, thereby making it possible to guarantee stability of a principle of recording in the present embodiment. 3-3) Recording characteristics common to organic dye recording film in the present embodiment As one of "3-2-B] basic characteristics common to an organic dye recording material in the present embodiment", the present embodiment is featured by recording power control, as described in item [y] . The formation of the recording mark 9 due to a local optical characteristic change in the recording layer 3-2 occurs at a temperature, which is much lower than a plastic deformation temperature of the conventional transparent substrate 2-2, at a thermal decomposition temperature in the recording layer 3-2, or a gasification (evaporation) temperature. Thus, an upper limit value of recording power is restricted so as not ensure that the transparent substrate 2-2 locally exceeds a plastic deformation temperature at the time of recording or a thermal decomposition temperature or a gasification (evaporation) temperature is locally exceeded in the recording layer 3-2. In parallel to discussion using thermal analysis, by using an apparatus described later in "4-1) Description of structure and characteristics of reproducing apparatus or recording/reproducing apparatus in the present embodiment" and by using a recording condition described later in "4-3) Description of recording condition in the present embodiment", there has been made a demonstration of a value of optimal power in the case where recording has been carried out in a principle of recording shown in the present embodiment. A numerical aperture (NA) value of an objective lens in the recording/reproducing apparatus used in a demonstration test has been 0.65, and a line speed at the time of recording has been 6.61 m/s. As a value of recording power (Peak Power) defined later in "4-3) Description of recording condition in the present embodiment", it has been found that: • Gasification (evaporation) occurs with most of an organic dye recording material at 30 mW, and a cavity occurs in a recording mark; A temperature of the transparent substrate 2-2 at a position in the vicinity of the recording layer 3- 2 significantly exceeds a glass transition temperature; • A temperature of the transparent substrate 2-2 at a position in the vicinity of the recording layer 3-2 reaches a plastic deformation temperature (glass transition temperature) at 20 mW; • 15 mW or less is desirable in consideration of a margin such as surface pre-warping or recording power change of an information storage medium. The "recording power" described above denotes a sum of exposure amount irradiated to the recording layer 3-2. The optical energy density at a center part of a focusing spot and at a portion at which the optical intensity density is the highest is obtained as parameters targeted for discussion in the present embodiment. The focusing spot size is inversely proportional to the NA value, and thus, the optical energy density at the center part of the focusing spot increases in proportion to a square of the NA value. Therefore, the current value can be converted to a value of optimal recording power in the B format described later or another format (another NA value) shown in FIG. 1 (D3) by using a relational formula below: [Recording power applicable to different NA values] = [Recording power when NA = 0.65] x 0.652/NA2 (5) Further, optimal recording power changes depending on a line speed V in phase change type recording material. In general, it is said that optimal recording power changes in proportion to a 1/2 square of a line speed V in phase change type recording material, and changes in proportion to a line speed V in organic dye recording material. Therefore, a conversion formula of optimal recording power considering a line speed V, obtained by extending formula (5), is obtained as follows: [General recording power] = [Recording power when NA = 0.65; 6.6 m/s] x (0.65/NA)2 x (V/6.6) (6) or [General recording power] = [Recording power when NA = 0.65; 6.6 m/s] x (0.65/NA)2 x (V/6.6)l/2 (7) When the above discussion result is summarized, as recording power for guaranteeing a principle of recording shown in the present embodiment, it is desirable to set an upper limit value such as: [Optimal recording power] [Optimal recording power] [Optimal recording power] [Optimal recording power] [Optimal recording power] [Optimal recording power] From among the above formulas, a condition for formula (8) or formula (9) is obtained as a mandatory condition; a target condition for formula (10) or formula (11) is obtained; and a condition for formula (12) or formula (13) is obtained as a desirable condition. 3-4) Description of characteristics relating to "H-L" recording film in the present embodiment A recording film having characteristics that a light reflection amount in a recording mark 9 is lower than that in an unrecorded area is referred to as an "H-L" recording film. In contrast, a recording film in which the above light reflection amount is high is referred to as an "L-H" recording film. Among them, with respect to the "H-L" recording film, the present embodiment is featured in that: 1) an upper limit value is provided at a ratio of absorbance at a reproduction wavelength relevant to absorbance at a Viax write position of light absorption spectra; and 2) a light absorption spectra profile is changed to form a recording mark. A detailed description relating to the above contents will be given with reference to FIGS. 9 and 10. In the "H-L" recording film in the present embodiment, as shown in FIG. 9, a wavelength of A.max write is shorter than a use wavelength utilized for recording/reproduction (in the vicinity of 405 nm). As is evident from FIG. 10, in the vicinity of a wavelength of A,max write' change of absorbance is small between an unrecorded portion and a recorded portion. If a change of absorbance is small between the unrecorded portion and the recorded portion, a large reproduction signal amplitude cannot be obtained. Even if a wavelength change of a recording or reproducing laser light source occurs, in view of the fact that recording or reproduction can be stably carried out, in the present embodiment, as shown in FIG. 9, a design of the recording film 3-2 is made so that a wavelength of A,max Write arrives at the outside ranging from 355 nm to 455 nm, i.e., arrives at the shorter wavelength side than 355 nm. The relative absorbance at 355 nm, 455 run, and 405 nm described in "Chapter 0: Description of Relationship between Use Wavelength and the Present Embodiment" when the absorbance at a position of A,max write defined in "2-1) Difference in principle of recording/recording film structure and difference in basic concept relating to reproduction signal generation", is defined as Ah355, Ah455, and Ah4Q5. In the case where of Ah4Q5 = 0.0, the light reflection factor from a recording film in an unrecorded state coincides with that at 405 nm in the light reflection layer 4-2. A light reflection factor of the light reflection layer 4-2 will be described later in detail in the section "6-1) Light reflection layer". Hereinafter, a description will be given with respect to the fact that the light reflection factor of the light reflection layer 4-2 is defined as 100% for the sake of simplification. In the write-once type information storage medium using an "H-L" recording film in the present embodiment, a reproduction circuit is used in common to a case of using a read-only type information storage medium (HD DVD-ROM disk) in the case of a one-sided single layer film. Therefore, in this case, an optical reflection factor is defined as 45% to 85% in accordance with a light reflection factor of the reflection only information storage medium (HD DVD-ROM disk) of a one-sided single layer film. Therefore, it is necessary to set the light reflection factor at an unrecorded position to 40% or more. Because 1 - 0.4 = 0.6, it is possible to intuitively understand whether or not the absorbance Ah4Q5 at 405 nm may be set: Ah405 In the case where formula (14) above is met, it is possible to easily understand that the light reflection factor can be set to 40% or more. Thus, in the present embodiment, an organic dye recording material, which meets formula (14) in an unrecorded location, is selected. The above formula (14) assumes that, in FIG. 9, the light reflection factor is obtained as 0% when the light reflection layer 4-2 is reflected over the recording layer 3-2 with a light beam having a wavelength of A,max write- However, in reality, at this time, the light reflection factor is not obtained as 0%, and has a certain degree of light reflection factor. Thus, strictly, there is a need for correction relevant to formula (14). In FIG. 9, if the light reflection factor is defined as RXmax write when the light reflection layer 4-2 has been reflected over the recording layer 3-2 with a light beam having a wavelength of A,max Write' a strict conditional formula in which the light reflection factor at an unrecorded position is set to 40% or more is obtained as follows: I - Ah405 x (1 - R^max write) ^ 0.4 (15) In the "H-L" recording layer, in many cases, write) - °-25, and thus, formula (15) is established as follows: Ah4o5 0.8 (16) In the "H-L" recording film according to the present embodiment, it is conditionally mandatory to meet formula (16). Characteristics of the above formula (14) has been provided, and further, a detailed optical film design has been made under a condition that the film thickness of the recording layer 3-2 meets the condition for formula (3) or formula (4), in consideration of a variety of margins such as a film thickness change or a wavelength change of reproduction light. As a result, it has been found desirable that: Ah405 0.3 (17) Assuming that formula (14) is established, when: the recording/reproducing characteristics are more stable. This is because, in the case where formula (14) meets any of at least formulas (18) and (19) when formula (14) is established, the value of Ah becomes 0.6 or less in the range of 355 nm to 405 nm or in the range of 405 nm to 455 nm (occasionally in the range of 355 nm to 455 nm), and thus, even if a fluctuation occurs at a light emission wavelength of a recording laser light source (or a reproducing laser light source), a value of absorbance does not change drastically. As a specific principle of recording of the "H-L" recording film in the present embodiment, there is utilized a phenomenon of "array change between molecules" or "molecular structure change in molecule" in a recording mechanism listed in item [a] in "3-2-B] Basic featured common to organic dye recording material in the present embodiment" which has been described as a specific principle of recording of the "H-L" recording film in the present embodiment. As a result, as described in the above item (2), a light absorption spectrum profile is changed. The light absorption spectrum profile in a recording mark in the present embodiment is indicated by the solid line shown in FIG. 10, and the light absorption spectrum profile in an unrecorded location is superimposed by the dashed line, thereby making it possible to compare these profiles with each other. In the present embodiment, the light absorption spectrum profile in the recording mark changes comparatively broadly, and there is a possibility that a molecular structure change in molecules occurs and partial precipitation (coal tar) of carbon atoms occurs. The present embodiment is featured in that a value of a wavelength ^-Imax a^ which the absorbance in the recording mark becomes maximal is made closer to a reproduction wavelength of 405 nm than a value of a wavelength write at an unrecorded position, thereby generating a reproduction signal in the "H-L" recording film. In this manner, the absorbance at the wavelength A,lmax at which the absorbance is the highest becomes smaller than "1", and a value of the absorbance A14Q5 at a reproduction wavelength of 405 nm becomes greater than a value of Ah4Q5- As a result, a total light reflection factor in a recording mark is lowered. In the H format in the present embodiment, as a modulation system, there is employed ETM (Eight to Twelve: 8-bit data code is converted to 12-channel bit) and RLL (1, 10) (Among a code train after modulated, a minimum inversion length relevant to a 12-channel bit length T is 2T, and a maximum inversion length is 11T). Where performance evaluation of a reproduction circuit described later in "4-2) Description of reproducing circuit in the present embodiment) is carried out, in order to stably carry out reproduction by the reproducing circuit, it has been found necessary to meet that a ratio of [differential value 111 = IHH ~ IHL between the I11H and reproduction signal amount IHL from a recording mark having a sufficiently long length (11T)] is: I11/I11H °-4 (2°) or preferably, I11/I11H > 0.2 (21) In the present embodiment, a PRML method is utilized at the time of signal reproduction recorded at high density, and a signal processor circuit and a state transition chart shown in FIGS. 15 to 17 is used (A detailed description is given later). In order to precisely carry out detection in accordance with a PRML technique, the linearity of a reproduction signal is requested. The characteristic of the signal processor circuit shown in FIGS. 15 and 16 has been analyzed based on the state transition chart shown in FIG. 17, in order to ensure the linearity of the above reproduction signal. As a result, it has been found necessary to meet that a ratio relevant to the above of a value when a recording mark having a length of 3T and a reproduction signal amplitude from a repetition signal of an unrecorded space is defined as 13 meets: l3/Ill 0.35 (22); or desirably, I3/In 0.2 (23) In view of a condition for the above formula (16), the present embodiment is technically featured in that a value of AlQS been set so as to meet formulas (20) and (21). Referring to formula (16), the following is obtained: 1 - 0.3 = 0.7 (24) In view of formula (24), from a correlation with formula (20), the following condition is derived: (A1405 ~ 0.3)/0.7 0.4, that is, A1405 2. 0.58 (25) Formula (25) is a formula derived from a very coarse result of discussion, and is merely shown as a basic concept. Because the Ah4Q5 setting range is specified in accordance with formula (16), in the present embodiment, at least a condition for A14Q5 is mandatory as: A1405 > 0.3 (26) As a method for selecting an organic dye material suitable to a specific "H-L" recording layer, there is selected an organic dye material for which, in the present embodiment, based on an optical film design, a refractive factor range in an unrecorded state is 1.3 to 2.0; the absorption coefficient range is 0.1 to 0.2, desirably n32 = 1.7 to 1.9; the absorption coefficient range is k-2 = 0.15 to 0.17, and a series of conditions described above are met. In the "H-L" recording film shown in FIG. 9 or 10, in light absorption spectra in an unrecorded area, although a wavelength of write is shorter than a wavelength of reproduction light or recording/reproducing light (for example, 405 nm), the wavelength of write longer than a wavelength of reproduction light or recording/reproducing light (for example, 405 nm), without being limited thereto. In odder to meet the above formula (22) or formula (23), the thickness Dg of the recording layer 3-2 is influenced. For example, if the thickness Dg of the recording layer 3-2 significantly exceeds an allowable value, optical characteristics of only a part coming into contact with the transparent substrate 2-2 in the recording layer 3-2 are changed as a state that follows forming of the recording mark 9, whereby the optical characteristics of a portion coming into contact with the light reflection layer 4-2 adjacent to its location are obtained as a value equal to that in the unrecorded area. As a result, a reproduction light amount change is lowered, and a value of 13 in formula (22) or formula (23) is reduced, and a condition for formula (22) or formula (23) cannot be met. Therefore, in order to meet formula (22), as shown in FIGS. 8B and 8C, it is necessary to make a change to the optical characteristics of a portion which comes into contact with the light reflection layer 4-2 in the recording mark 9. Further, if the thickness Dg of the recording layer 3-2 significantly exceeds an allowable value, a temperature gradient occurs in the thickness direction in the recording layer 3-2 when the recording mark is formed. Then, before reaching the optical characteristic change temperature at a portion coming into contact with the light reflection layer 4-2 in the recording layer 3-2, a gasification (evaporation) temperature of a portion coming into contact with the transparent substrate 2-2 is exceeded or a thermal deformation temperature is exceeded in the transparent substrate 2-2. For the above reason, in the present embodiment, in order to meet formula (22), the thickness Dg of the recording layer 3-2 is set to "3T" or less based on the discussion of thermal analysis; and a condition meeting formula (23) is such that the thickness Dg of the recording layer 3-2 is set to "3 x 3T" or less. Basically, in the case where the thickness Dg of the recording layer 3-2 is equal to or smaller than "3T", although formula (22) can be met, the thickness may be set to "T" or less in consideration of effect of a tilt due to a facial motion or warping of the write-once type information storage medium or a margin relevant to a focal blurring. In consideration of a result obtained by formulas (1) and (2) described previously, the thickness Dg of the recording layer 3-2 in the present embodiment is set in the range assigned in a required minimum condition that: 9T > Dg > X/8n32 (27) and in a desired condition that: 3T > Dg > X/4n32 (28) Without being limited thereto, the severest condition can be defined as: T > Dg > L/4n32 (29) As described later, a value of the channel bit length T is 102 nm in the H format, and is 69 nm to 80 nm in the B format. Thus, a value of 3T is 306 nm in the H format and is 207 nm to 240 nm in the B format. A value of 9T is 918 nm in the H format and is 621 nm to 720 nm in the B format. Here, although an "H-L" recording film has been described, the conditions for formulas (27) to (29) can be applied to an "L-H" recording film without being limited thereto. Chapter 4 Description of Reproducing Apparatus or Recording/Reproducing Apparatus and Recording Condition/Reproducing Circuit 4-1) Description of structure and characteristics of reproducing apparatus or recording/reproducing apparatus in the present embodiment FIG. 11 shows an illustration of a structure in an embodiment of an information recording/reproducing apparatus. In FIG. 11, an upper side of a control unit 143 mainly indicates an information recording control system for an information storage medium. In the embodiment of the information reproducing apparatus, a structure excluding the information recording control system in FIG. 11 corresponds to the above structure. In FIG. 11, the arrow drawn by the thick solid line indicates a flow of main information which designates a reproduction signal or a recording signal; the arrow of the thin solid line denotes a flow of information; the arrow of the one-dotted chain line denotes a reference clock line; and the arrow of the thin dashed line denotes a command indicating direction. An optical head (not shown) is arranged in an information recording/reproducing unit 141 shown in FIG. 11. In the present embodiment, although a wavelength of a light source (semiconductor laser) used in the optical head is 405 nm, the present embodiment is not limited thereto, and there can be used a light source having a use wavelength equal to or shorter than 620 nm or 530 nm or a light source ranging from 355 nm to 455 nm, as described previously. In addition, two objective lenses used to focus the light beam having the above wavelength onto the information storage medium may be incorporated in the optical head. In the case where a recording/reproducing operation is carried out with respect to an information storage medium in the H format, an objective lens having a NA value of 0.65 is used. A structure is provided such that, in the case where a recording/reproducing operation is carried out with respect to an information storage medium in the B format, an objective lens having NA = 0.85 is used. As an intensity distribution of incident light immediately before the light is incident to an objective lens, the relative intensity at the periphery of the objective lens (at the boundary position of an aperture) when the center intensity is set to "1" is referred to as "RIM Intensity". A value of the RIM intensity in the H format is set in the range of 55% to 70%. At this time, a wave surface aberration amount in the optical head is optically designed so as to be 0.33A, (0.33X or less) with respect to a use wavelength A,. In the present embodiment, a partial response maximum likelihood (PRML) is used for information reproduction to achieve high density of an information storage medium (FIG. 1, point [A]). As a result of a variety of tests, when PR(1, 2, 2, 2, 1) is used as a PR class to be used, line density can be increased and the reliability of a reproduction signal can be improved (i.e., demodulation reliability can be improved) when a servo correction error such as a focal blurring or a track shift has occurred. Thus, in the present embodiment, PR(1, 2, 2, 2, 1) is employed (FIG. 1, point [Al]). In the present embodiment, a channel bit pattern after modulated is recorded in an information storage medium in accordance with a (d, k; m, n) modulation rule (In the above described method, this denotes RLL(d, k) of m/n modulation). Specifically, ETM (Eight to Twelve Modulation) for converting 8-bit data to a 12-channel bit (m = 8, n = 12) is employed as a modulation system, and a condition of RLL (1, 10) in which a minimum value having continuous "0"s is defined as d = 1, and a maximum value is defined as k = 10 as a run length limited RLL restriction for apply limitation to a length that follows "0" in the channel bit pattern after modulated must be met. In the present embodiment, in order to achieve high density of an information storage medium, a channel bit gap is reduced to the minimum. As a result, for example, after a pattern "101010101010101010101010" which is a repetition of a pattern of d = 1 has been recorded in the information storage medium, in the case where the data is reproduced in an information recording/reproducing unit 141, the data is close to a shutdown frequency having MTF characteristics of a reproducing optical system, and thus, a signal amplitude of a reproduced raw signal is formed in a shape almost hidden by noise. Therefore, a partial response maximum likelihood (PRML) technique is used as a method for thus reproducing a recording mark or a pit, which has been dense up to the vicinity of a limit of the MTF characteristics (shutdown frequency). That is, a signal reproduced from the information recording/reproducing unit 141 receives reproducing waveform correction by a PR equalizer circuit 130. A signal having passed through the PR equalizer circuit 130 is sampled by converting a signal after passing through the PR equalizer circuit 130 to a digital amount in accordance with a timing of a reference clock 198 sent from a reference clock generating circuit 160; the sampled signal is converted to a digital data by an AD converter 169; and a Viterbi decoding process is carried out in a Viterbi decoder 156. The data after Viterbi-decoded is processed as data, which is completely similar to binary data at a conventional slice level. In the case where the PRML technique has been employed, if a sampling timing obtained by the AD converter 169 is shifted, an error rate of the data after Viterbi decoded increases. Therefore, in order to enhance precision of the sampling timing, the information reproducing apparatus or information recording/reproducing apparatus according to the present embodiment has another sampling timing sampling circuit in particular (combination of Schmidt trigger binarizing circuit 155 and PLL circuit 174). This Schmidt trigger circuit 155 has a specific value (forward direction voltage value of diode in actuality) at a slice reference level for binarizing, and is featured in that binarizing is provide only when the specific width has been exceeded. Therefore, for example, as described above, in the case where a pattern of "101010101010101010101010" has been input, a signal amplitude is very small, and thus, switching of binarizing does not occur. In the case where "1001001001001001001001" or the like, for example, being a pattern of a rarer fraction than the above, has been input, an amplitude of a reproducing raw signal increases, and thus, the polarity switching of a binary signal occurs in accordance with a timing of "1" by a Schmidt trigger binarizing circuit 155. In the present embodiment, an NRZI (Non Return to Zero Invert) technique is employed, and a position of "1" of the above pattern coincides with an edge section (boundary section) of a recording mark or a pit. A PLL circuit 174 detects a shift in frequency and phase between a binary signal which is an output of this Schmidt trigger binarizing circuit 155 and a signal of a reference clock 198 sent from a reference clock generating circuit 160 to change the frequency and phase of the output clock of the PLL circuit 174. A reference clock generating circuit 160 applies a feedback to (a frequency and a phase) of a reference clock 198 so as to lower an error rate after Viterbi decoded, by using an output signal of this PLL circuit 174 and decoding characteristic information on a Viterbi decoder 156 and a convergence length (information on (distance to convergence)) in a path metric memory in the Viterbi decoder 156, although is not specifically shown). The reference clock 198 generated by this reference clock generating circuit 160 is utilized as a reference timing at the time of reproduction signal processing. A sync code position sampling unit 145 serves to detect the presence and position of a sync code, which coexists in an output data train of the Viterbi decoder 156 and to sample a start position of the above output data. While this start position is defined as a reference, a demodulator circuit 152 carries out a demodulating process with respect to data temporarily stored in a shift resistor circuit 170. In the present embodiment, the above temporarily stored data is returned to its original bit pattern with reference to a conversion table recorded in a demodulating conversion table recording unit 154 on 12-channel bit by bit basis. Then, an error correcting process is performed by an ECC decoding circuit 162, and descrambling is carried out by a descrambling circuit 159. Address information is recorded in advance by wobble modulation in a recording type (rewritable type or write-once type) information storage medium according to the present embodiment. A wobble signal detecting unit 135 reproduces this address information (i.e., judges the contents of a wobble signal), and supplies information required to provide an access to a desired location to the control unit 143. A description will be given with respect to an information recording control system provided at the upper side than the control unit 143. After data ID information has been generated from a data ID generating unit 165 in accordance with a recording position on an information storage medium, when copy control information is generated by a CPR_MAI data generating unit 167, a variety of information on data ID, IED, CPRJMAI, and EDC is added to information to be recorded by a data ID, IED, CPR_MAI, and EDC adding unit 168. After the added information has been descrambled by the descrambling circuit 157, an ECC block is formed by an ECC encoding circuit 161, and the ECC block is converted to a channel bit pattern by a modulating circuit 151. A sync code is added by a sync code generating/adding unit 146, and data is recorded in an information storage medium in the information recording/reproducing unit 141. At the time of modulation, DSV values after modulated are sequentially calculated by a DSV (Digital Sum Value) calculating unit 148, and the serially calculated values are fed back to code conversion after modulated. FIG. 12 shows a detailed structure of peripheral portions including the sync code position detector unit 145 shown in FIG. 11. A sync code is composed of a sync position detecting code section and a variable code section having a fixed pattern. From the channel bit pattern output from a Viterbi decoder, a sync position detecting code detector unit 182 detects a position of a sync position detecting code section having the above fixed pattern. Variable code transfer units 183 and 184 sample data on a variable code which exists before and after the detected position, and judge in which sync frame in a sector the sync code is positioned, the sync code being detected by an identifying unit 185 for detecting a sync position having the above fixed pattern. User information recorded on an information storage medium is sequentially transferred in order of a shift register circuit 170, a demodulation processing unit 188 in a demodulator circuit 152, and an ECC decoding circuit 162. In the present embodiment, in the H format, the high density of the information storage medium is achieved (in particular, line density is improved) by using the PRML system for reproduction in a data area, a data lead-in area, and a data lead-out area. In addition, compatibility with a current DVD is ensured and reproduction stability is ensured by using a slice level detecting system for reproducing in a system lead-in area and a system lead-out area. (A detailed description will be given later in "Chapter 7: Description of H Format".) 4-2) Description of reproducing circuit in the present embodiment FIG. 13 shows an embodiment of a signal reproducing circuit using a slice level detecting system used at the time of reproduction in a system lead-in area and a system lead-out area. A quadrature optical detector 302 in FIG. 13 is fixed into the optical head, which exists in the information recording/reproducing unit 141 in FIG. 11. Hereinafter, a signal having taken a sum of detection signals obtained from optical detecting cells la, Ib, Ic, and Id of the quadrature optical detector 302 is referred to as a "lead channel 1 signal". From a preamplifier 304 to a slicer 310 in FIG. 13 corresponds to a detailed structure in the slice level detecting circuit 132 in FIG. 11. A reproduction signal obtained from an information storage medium is subjected to a waveform equalizing process by a pre-equalizer 308 after the signal has passed through a high path filter 306 which shuts out a frequency component lower than a reproduction signal frequency bandwidth. According to testing, it has found that this pre-equalizer 308 minimizes a circuit scale by using a 7-tap equalizer and can detect a reproduction signal precisely. Thus, in the present embodiment, the 7-tap equalizer is used. A VFO circuit/PLL 312 in FIG. 13 corresponds to the PLL circuit 174 in FIG. 11; and a demodulating/ECC decoding circuit 314 in FIG. 13 corresponding to the decoding circuit 152 and the ECC decoding circuit 162 in FIG. 11. FIG. 14 shows a detailed structure in a circuit of the slicer 310 in FIG. 13. A binary signal after sliced is generated by using a comparator 316. In response to an inverting signal of binary data after binarized is set at a slice level at the time of binarizing. In the present embodiment, a cutoff frequency of this low path filter is set to 5 KHz. When this cutoff frequency is high, a slice level change is fast, and the low path filter is affected by noise. In contrast, if a cutoff frequency is low, a slice level response is slow, and thus, the filter is affected by dust or scratch on the information storage medium. The cutoff frequency is set to 5 KHz in consideration of a relationship between RLL(1, 10) and a reference frequency of a channel bit described previously. FIG. 15 shows a signal processor circuit using a PRML detecting technique used for signal reproduction in a data area, a data lead-in area, and a data leadout area. A quadrature optical detector 302 in FIG. 15 is fixed into the optical head, which exists in the information recording/reproducing unit 141 in FIG. 11. Hereinafter, a signal having taken a sum of detection signals obtained from the optical detecting cells la, lb, Ic, and Id of the quadrature optical detector 302 is referred to as a "lead channel 1 signal". A derailed structure in the PR equalizer circuit 130 in FIG. 11 is composed of circuits from a preamplifier 304 to a tap controller 332, an equalizer 330, and an offset canceller 336 in FIG. 15. A PLL circuit 334 in FIG. 15 is a part in the PR equalizer circuit 130, and denotes an element other than the Schmidt trigger binarizing circuit 155. A primary cutoff frequency of a high path filter circuit 306 in FIG. 15 is set at 1 KHz. A pre-equalizer circuit 308 uses a 7-tap equalizer in the same manner as that in FIG. 13 (because the use of the 7-tap equalizer minimizes a circuit scale and can detect a reproduction signal precisely). A sample clock frequency of an A/D converter circuit 324 is set to 72 MHz, and a digital output is produced as an eight-bit output. In the PRML detecting technique, if a reproduction signal is affected by a level change (DC offset) of its entire signal, an error is likely to occur at the time of Viterbi demodulation. In order to eliminate such an effect, there is provided a structure of correcting an offset by the offset canceller 336 using a signal obtained from an equalizer output. In the embodiment shown in FIG. 15, an adaptive equalizing process is carried out in the PR equalizer circuit 130. Thus, a tap controller for automatically correcting tap coefficients in the equalizer 330 is utilized by utilizing an output signal of the Viterbi decoder 156. FIG. 16 shows a structure in the Viterbi decoder 156 shown in FIG. 11 or 15. A branch metric relevant to all branches, which can be predicted in response to an input signal, is calculated by a branch metric calculating unit 340, and the calculated value is sent to an ACS 342. The ACS 342 is an acronym of Add Compare Select, which calculates a path metric obtained by adding branch metrics in response to each of the passes which can be predicted in the ACS 342 and transfers the calculation result to a path metric memory 350. At this time, in the ACS 342, a calculating process is carried out with reference to the information contained in the path metric memory 350. A path memory 346 temporarily stores a value of the path metric corresponding to each path (transition) state and such each path, which can be predicted in the memory 346, the value being calculated by the ACS 342. An output switch unit 348 compares a path metric corresponding to each path, and selects a path when a path metric value becomes minimal. FIG. 17 shows a state change in PR(1, 2, 2, 2, 1) class in the present embodiment. A change of a state which can be obtained in the PR(1, 2, 2, 2, 1) class can be made as only a change shown in FIG. 17, and a path which can exist (which can be predicted) at the time of decoding is identified in the Viterbi decoder 156 based on a transition chart in FIG. 17. 4-3) Description of recording condition in the present embodiment "A description of optimal recording power (peak power) in the present embodiment has been given in "3-3) Recording characteristics common to organic dye recording film in the present embodiment". Referring to FIG. 18, a description will be given with respect to a recording waveform (exposure condition at the time of recording) used when the optimal recording power is checked. The exposure levels at the time of recording have four levels of recording power (peak power), bias power 1, bias power 2, and bias power 3. When a long (4T or more) recording mark 9 is formed, modulation is carried out in the form of multi-pulses between recording power (peak power) and bias power 3. In the present embodiment, in any of the H format and B format systems, a minimum mark length relevant to a channel bit length T is obtained as 2T. In the case where this minimum mark of 2T is recorded, one write pulse of recording power (peak power) after bias power 1 is used as shown in FIG. 18, and bias power 2 is temporarily obtained immediately after the write pulse. In the case where a 3T recording mark 9 is recorded, bias power 2 is temporarily used after exposing two write pulses, a first pulse and a last pulse of recording power (peak power) level that follows bias power 1. In the case where a recording mark 9 having a length of 4T or more is recorded, bias power 2 is used after multipulse and write pulse exposure. The vertical dashed line in FIG. 18 shows a channel clock cycle. In the case where a 2T minimum mark is recorded, the laser power is risen at a position delayed by TSFP from a clock edge, and fallen at a position, which is backward by TELP from an edge of a succeeding clock. A cycle during which the laser power is set at bias power 2 is defined as TLO Values of TSFP, TELp, and TLC are recorded in physical format information PFI contained in a control data zone CDZ as described later in the case of the H format. In the case where a 3T or more long recording mark is formed, the laser power is risen at a position delayed by TSFP from a clock edge, and lastly, ended with a last pulse. Immediately after the last pulse, the laser power is kept at the bias power 2 during a period of TLQ. Shift times from a clock edge to a rise/fall timing of the last pulse are defined as TSLP^ TELP- In addition, a shift time from a clock edge to a fall timing of the last pulse is defined as TEEp, and further, an interval of a single pulse of a multi-pulse is defined as T^p. Each of intervals TELP - TSFP, TMP, TELP - TSLP, and TLC is defined as a half-value wide relevant to a maximum value, as shown in FIG. 19. In addition, in the present embodiment, the above parameter setting range is defined as follows: 0.25T O.OOT LOOT - 0.10T O.OOT 0.1ST Further, in the present embodiment, the values of the above described parameters can be changed as shown in FIGS. 20A, 20B and 20C according to a recording mark length (Mark Length) and the immediately preceding/immediately succeeding space length (Leading/Trailing space length). FIGS. 21A, 21B and 21C each shows parameter values when optimal recording power of the write-once type information storage medium recorded in a principle of recording shown in the present embodiment has been checked, as described in the section "3-3) Recording characteristics common to organic dye recording film in the present embodiment". At this time, the values of bias power 1, bias power 2, and bias power 3 are 2.6 mW, 1.7 mW, and 1.7 mW, and reproduction power is 0.4 mW. Chapter 5: Specific Description of Organic Dye Recording Film in the Present Embodiment 5-1) Description of characteristics relating to "L-H" recording film in the present embodiment A description will be given with respect to an "LH" recording film having characteristics in which a light reflection amount is lowered in a recording mark as compared with that in an unrecorded area. From among principles of recording described in "3-2-B] Basic characteristics common to organic dye recording material in the present embodiment", a principle of recording in the case of using this recording film mainly utilizes any of: - Chromogenic characteristic change; - Change of electron structure (electron orbit) relevant to elements which contribute to chromogenic phenomenon [discoloring action or the like]; and - Array change between molecules, and changes characteristics of light absorption spectra. The "L-H" recording film is featured in that the reflection amount range in an unrecorded location and a recorded location has been specified in view of characteristics of a read-only type information storage medium having a one-sided two-layered structure. FIG. 22 shows a light reflection factor range in an unrecorded area (nonrecording portion) of the "H-L" recording film and the "L-H" recording film according to the present embodiment. In the present embodiment, the lower limit value 8 of the reflection factor at the non-recording portion of the "H-L" recording film is specified so as to be higher than an upper limit value y at the nonrecording portion of the "L-H" recording film. When the above information storage medium has been mounted on an information recording/reproducing apparatus or an information reproducing apparatus, a light reflection factor of the non-recording portion is measured by the slice level detector unit 132 or the PR equalizer circuit 130 shown in FIG. 11, thereby making it possible to judge whether the film is the "H-L" recording film or "L-H" recording film, and thus, making it very easy to judge type of recording film. Measurement has been carried out while producing the "H-L" recording film and the "L-H" recording film under a changed manufacturing condition, when a light reflection factor a between the lower limit value 8 at the non-recording portion of the "H-L" recording film and the upper limit value y at the non-recording portion of the "L-H" recording film is set in the range of 32% to 40%. As a result, it has been found that high manufacturing performance of the recording film is obtained and medium cost reduction is facilitated. After an optical reflection factor range 801 of a nonrecording portion ("L" portion) of the "L-H" recording film is made coincident with a light reflection factor range 803 of a one-sided double recording layer in the read-only type information storage medium, when a light reflection factor range 802 of a non-recording portion ("H" portion") of the "H-L" recording film is made coincident with a light reflection factor range 804 of a one-sided single layer in the read-only type information storage medium, a reproducing circuit of the information reproducing apparatus can be used in common to be well compatible with the read-only type information storage medium, and thus, the information reproducing apparatus can be produced inexpensively. Measurement has been carried out while producing the "H-L" recording film and the "L-H" recording film under a variety of changed manufacturing conditions, in order to facilitate price reduction of a medium while improving the manufacturing performance of the recording film. As a result, the lower limit value (3 of the light reflection factor of the non-recording portion ("L" portion) of the "L-H" recording film is set to 18%, and the upper limit value y is set to 32%; and the lower limit value 8 of the light reflection factor of the non-recording portion ("H" portion) of the "H-L" recording film is set to 40%, and the upper limit value e is set to 85%. FIGS. 23 and 24 show reflection factors at a nonrecording position and a recorded position in a variety of recording films in the present embodiment. In the case where an H format has been employed (refer to "Chapter 7: Description of H Format"), an optical reflection factor range at the non-recording portion is specified as shown in FIG. 22, whereby a signal appears in a same direction in an emboss area (such as system leas-in area SYLDI) and a recording mark area (data lead-in area DTLDI, data lead-out area DTLDO, or data area DTA) in the "L-H" recording film while a groove level is defined as a reference. Similarly, in the "HL" recording film, while a groove level is defined as a reference, a signal appears in an opposite direction in an emboss area (such as system lead-in area SYSDI) and a recording mark area (data lead-in area DTLDI, data lead-out area DTLDO, or data area DTA). Utilizing this phenomenon, a detecting circuit design corresponding to the "L-H" recording film and "H-L" recording film is facilitated in addition to use for recording film identification between the "L-H" recording film and the "H-L" recording film. In addition, the reproduction signal characteristics obtained from a recording mark recorded on the "L-H" recording film shown in the present embodiment is adjusted to conform to signal characteristics obtained from the "H-L" recording film to meet formulas (20) to (23). In this manner, in the case of using either one of the "L-H" recording film and the "H-L" recording film, the same signal processor circuit can be used, and the signal processor circuit can be simplified and reduced in price. 5-2) Characteristics of light absorption spectra relating to "L-H" recording film in the present embodiment As has been described in "3-4) Description of characteristics relating to "H-L" recording film in the present embodiment, the relative absorbance in an unrecorded area is basically low in the "H-L" recording film, and thus, when reproduction light has been irradiated at the time of reproduction, there occurs an optical characteristic change generated by absorbing energy of the reproduction light. Even if an optical characteristic change (update of recording action) has occurred after the energy of the reproduction light has been absorbed in a recording mark having high absorbance, a light reflection factor from the recording mark is lowered. Thus, reproduction signal processing is less affected because such a change works in a direction in which an amplitude of a reproduction signal (In = IHH ~ ^IIL.) °f tne reproduction signal increases. In contrast, the "L-H" recording film has optical characteristics that "a light reflection factor of an unrecorded portion is lower than that in a recording mark". This means that, as is evident from the contents described with respect to FIG. 2B, the absorbance of the unrecorded portion is higher than that in the recording mark. Thus, in the "L-H" recording film, signal degradation at the time of reproduction is likely to occur as compared with the "H-L" recording film. As described in "3-2-B] Basic characteristics common to organic dye recording material in the invention", there is a need for improving reliability of reproduction information in the case where reproduction signal degradation has occurred due to ultraviolet ray or reproduction light irradiation". As a result of checking the characteristics of an organic dye recording material in detail, it has been found that a mechanism of absorbing the energy of reproduction light to cause an optical characteristic change is substantially analogous to that of an optical characteristic change due to ultraviolet ray irradiation. As a result, if there is provided a structure of improving durability relevant to ultraviolet ray irradiation in an unrecorded area, signal degradation at the time of reproduction hardly occurs. Thus, the present embodiment is featured in that, in the "L-H" recording film, a value of Xmax write (maximum absorption wavelength which is the closest to wavelength of recording light) is longer than a wavelength of recording light or reproduction light (close to 405 nm). In this manner, the absorbance relevant to the ultraviolet ray can be reduced, and the durability relevant to ultraviolet ray irradiation can be significantly improved. As is evident from FIG. 26, a difference in absorbance between a recorded portion and an unrecorded portion in the vicinity of A,max Write ^s small, and a degree of reproduction signal modulation (signal amplitude) in the case where the wavelength light in the vicinity of max write is reduced. In view of a wavelength change of a semiconductor laser light source, it is desirable that a sufficiently large degree of reproduction signal modulation (signal amplitude) be taken in the range of 355 nm to 455 nm. Therefore, in the present embodiment, a design of a recording film 3-2 is made so that a wavelength of A.max write exists out of the range of 355 nm to 455 nm (i.e., at a longer wavelength than 455 nm). FIG. 25 shows an example of light absorption spectra in the "L-H" recording film in the present embodiment. As described in "5-1) Description of features relating to "L-H" recording film, a lower limit value (3 of a light reflection factor at a nonrecording portion ("L" section) of the "L-H" recording film is set to 18%, and an upper limit value y is set to 32% in the present embodiment. From 1 - 0.32 = 0.68, in order to meet the above condition, it is possible to intuitively understand whether or not a value A14Q5 °f ^he absorbance in an unrecorded area at 405 nm should meet: A1405 68% (36) Although the light reflection factor at 405 nm of the light reflection layer 4-2 in FIGS. 2A and 2B is slightly lowered than 100%, it is assumed that the factor is almost close to 100% for the sake of simplification. Therefore, the light reflection factor when absorbance Al = 0 is almost 100%. In FIG. 25, the light reflection factor of the whole recording film at a wavelength of A,max Write is designated by write- At this time, assuming that the light reflection factor is zero (R-rnax write 0) / formula (36) is derived. However, in actuality, the factor is not set to "0", and thus, it is necessary to drive a severer formula. A severe conditional formula for setting the upper light value y of the light reflection factor of the non-recording portion '"L" portion) of the "L-H" recording film to 32% is given by: 1 - A1405 x (1 - R^max write) °-32 (37) In a conventional write-once type information storage medium, only the "H-L" recording film is used, and there is no accumulation of information relating to the "L-H" recording film. However, in the case of using the present embodiment described later in "5-3) Anion portion: azo metal complex + cation portion: dye" and "5-4) Using "copper" as azo metal complex + center metal", the most severest condition which meets formula (37) is obtained as: A1405 80% (38) In the case of using an organic dye recording material described later in the embodiment, when an optical design of a recording film is made including a margin such as a characteristic variation at the time of manufacture or a thickness change of the recording layer 3-2, it has been found that a minimum condition which meet the reflection factor described in the section "Description of featured relating to "L-H" recording film" in the present embodiment: A1405 > 40% (39) may be met. Further, by meeting either of: A1355 > 40% (40) A1455 > 40% (41) it is possible to ensure stable recording characteristics or reproduction characteristics even if a wavelength of a light source is changed in the range of 355 nm to 405 nm or in the range of 405 ran to 455 nm (in the range of 355 nm to 455 nm in the case where both of the formulas are met at the same time) . FIG. 26 shows a light absorption spectrum change after recorded in the "L-H" recording film according to the present embodiment. It is considered that a value of a maximum absorption wavelength Xlmax in a recording mark deviates from a wavelength of lmax write' anc* an inter-molecular array change (for example, an array change between azo metal complexes) occurs. Further, it is considered that a discoloring action (cutting of local electron orbit (local molecular link dissociation) ) occurs in parallel to a location in which both of the absorbance in location of ^lmax the absorbance Al at 405 nm are lowered and the light absorption spectra spreads itself. In the "L-H" recording film according to the present embodiment as well, by meeting each of formulas (20), (21), (22), and (23), the same signal processor circuit is made available for both of the "L-H" recording film and the "H-L" recording film, thereby promoting simplification and price reduction of the signal processor circuit. In formula (20), when: is modified, IllH IllL/0-6 (43) is obtained. As described previously, in the present embodiment, a lower limit value p of a light reflection factor of an unrecorded portion ("L" portion) of an "L-H" recording film is set to 18%, and this value corresponds to IHL- Further, conceptually, the above value corresponds to: IllH - 1 - Ah405 x (1 - RVax write) (44). Thus, from formulas (43) and (44), the following formula is established: 1 - Ah405 x (1 - RA-max write) 0.18/0.6 (45) If 1 - RX,max write ^ ®r formula (45) is modified as follows: Ah405 In comparison between the above formulas (46) and (36), it is found that the values of A14Q5 and Ah4Q5 may be seemingly set in the vicinity of 68% to 70% as values of absorbance. Further, in view of a case in which the value of A14Q5 is obtained in the range of formula (39) and performance stability of a signal processor circuit, a sever condition is obtained as: Ah405 If possible, it is desirable to meet; Ah405 0.3 (48) 5-3) Anion portion: Azo metal complex + cation portion: dye A description will be specifically given with respect to an organic dye material in the present embodiment having characteristics described in "5-1) Description of characteristics relating to "L-H" recording film in the present embodiment", the present embodiment meeting a condition shown in "5-2) Characteristics of optical absorption spectra relating to "L-H" recording film" in the present embodiment". The thickness of the recording layer 3-2 meets the conditions shown in formulas (3), (4), (27), and (28), and is formed by spinner coating (spin coating). For comparison, a description will be given by way of example. A crystal of a "salt" is assembled by "ion coupling" between positively charged "sodium ions" and negatively charged "chloride ions". Similarly, in polymers as well, there is a case in which a plurality of polymers are combined with each other in the form close to "ion coupling", forming configuring an organic dye material. The organic dye recording film 3-2 in the present embodiment is composed of a positively charged "cation portion" and a negatively charged "anion portion". In particular, the above recording film is technically featured in that: coupling stability is improved by utilizing a "dye" having chromogenic characteristics for the positively charged "cation portion" and utilizing an organic metal complex for the negatively charged "anion portion"; and there is met a condition that "8] an electron structure in a chromogenic area is stabilized, and structural decomposition relevant to ultraviolet ray or reproduction light irradiation hardly occurs" shown in "3-2-B] Basic feature common to organic dye recording material in the present embodiment". Specifically, in the present embodiment, an "azo metal complex" whose general structural formula is shown in FIG. 3 is utilized as an organic metal complex. In the present embodiment which comprises a combination of an anion portion and a cation portion, cobalt or nickel is used as a center metal M of this azo metal complex, thereby enhancing optical stability. There may be used: scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chrome, molybdenum, tungsten, manganese, technetium, rhenium, iron, ruthenium, osmium, rhodium, iridium, palladium, platinum, copper, silver, gold, zinc, cadmium, or mercury and the like without being limited thereto. In the present embodiment, as a dye used for the cation portion, there is used any of a cyanine dye whose general structural formula is shown in FIG. 27; a styril dye whose general structural formula is shown in FIG. 28; and a monomethine cyanine dye whose general structural formula is shown in FIG. 29. Although an azo metal complex is used for the anion portion in the present embodiment, a formazane metal complex whose general structural formula is shown in FIG. 30 may be used without being limited thereto, for example. The organic dye recording material comprising the anion portion and cation portion is first powdered. In the case of forming the recording layer 3-2, the powdered organic dye receding material is dissolved in organic solvent, and spin coating is carried out on the transparent substrate 2-2. At this time, the organic solvent to be used includes: a fluorine alcohol based TFP (tetrafluoro propanol) or pentane; hexane; cyclohexane; petroleum ether; ether or analogous, nitrile or analogous, and any of a nitro compound or sulfur-containing compound or a combination thereof. 5-4) Using "copper" as azo metal complex + center metal FIGS. 65 and 66 each show an example of a light spectrum change before and after recording (forming a recording mark) in an "H-L" recording film and an "L-H" recording film using an optical characteristic change according to the present embodiment as a principle of recording. A wavelength of X,max write before recording (in an unrecorded area) is defined as.bmax Write; a half value width of a light absorption spectrum (b) around this X,max write (a width of a wavelength area meeting a range of "A 0.5" when the absorbance A at krnax write is "1") is defined as Was; and a wavelength °f ^max write °f a light absorption spectrum (a) after recorded (in a recording mark) is defined as ^.amax write- The recording film 3-2 having the characteristics shown in FIGS. 65 and 66 utilizes a "change of an electron structure (electron orbit) relevant to elements which contribute to a chromogenic phenomenon and a "molecular structure change in molecules" from among the principles of recording shown in [a] of "3-2-B] Basic characteristics common to organic dye recording material in the invention". If there occurs a "change of an electron structure (electron orbit) relevant to electrons which contribute to a chromogenic phenomenon", for example, the dimensions or structure of the light emitting area 8 as shown in FIG. 3 changes. For example, if dimensions of the light emitting area 8 change, the resonant absorption wavelength of the local electrons also changes, and thus, the maximum absorption wavelength of light absorption spectra changes from raax Write to max write- Similarly, if a "molecular structure change in molecules" occurs, a structure of the light emitting area 8 also changes, and thus, the maximum absorption wavelength of the light absorption spectra also changes. When a change amount of the maximum absorption wavelength is defined as AA,max, the following relationship is established: A^max - I amax write ~"max write I (49) When the maximum absorption wavelength of the light absorption spectra thus changes, the half value width Was of the light absorption spectra also changes concurrently. A description will be given with respect to an effect on a reproduction signal obtained from a recording mark position when the maximum absorption wavelength of the light absorption spectra and the half value width Was of the light absorption spectra have thus changed at the same time. The light absorption spectra in a pre-recording/unrecorded area are represented as (b) in FIG. 65 (FIG. 66), and thus, the absorbance with a reproduction light beam having 405 nm is obtained as Ah4Q5 (Alos) If only the maximum absorption wavelength changes to Xamax write as optical spectra after recorded (in recording mark) and a change of the half value width Was has not occurred, the light absorption spectra are theoretically obtained as shown in (c) of FIG. 65 (FIG. 66). Then, the absorbance with a reproduction light beam having 405 nm changes to A405- However, in actuality, the half value width changes, and the absorbance after recorded (in recording mark) is obtained as A14Q5 (Ah4Q5). A change amount \|A]_4Q5 - Ah4Q5 of the absorbance before and after recorded is proportional to a reproduction signal amplitude value. Thus, in the example shown in FIG. 65 (FIG. 66), the maximum absorption wavelength change and the half width value change work as an offset action relevant to an increase of the reproduction signal amplitude. Therefore, there occurs a problem that a C/N ratio of a reproduction signal is impaired. A first application example of the present embodiment for solving the above problem is featured in that the characteristics of the recording layer 3-2 is set (film-designed) so that a maximum absorption wavelength change and a half value width change work relevant to an increase of the reproduction signal amplitude in a synergetic manner. That is, as is easily predicted from the change shown in FIG. 65 (FIG. 66), the characteristics of the recording layer 3-2 is set (film-designed) so that a change occurs in a direction in which a half value width widens independent of a moving direction of A,amax Write after recorded relevant to bmax write before recorded in the "H-L" recording film or in a direction in which the half value width narrows independent of a moving direction of A,amax write after recorded relevant to bmax write before recorded in the "L-H" recording film. Now, a second application example in the present embodiment will be described here. As described previously, there is a case in which the C/N ratio of the reproduction signal is lowered by offsetting a difference between Ah4Q5 and A1405 due to the maximum absorption wavelength change and the change of the half value width Was. Further, in the above first application example or the embodiment shown in FIG. 65 or FIG. 66, the maximum absorption wavelength change and the half value width Was of the light absorption spectra change at the same time, a value of the absorbance "A" after recorded (in recording mark) is affected by both of the maximum absorption wavelength change amount AXmax and the half value width change amount. When the write-once type information storage medium 12 has been mass-produced, it is difficult to precisely control values of both of the maximum absorption wavelength change amount A^max and the half value width change amount. Thus, when the information is recorded in the mass-produced write-once type information storage medium 12 has been recorded, a fluctuation of the reproduction signal amplitude increases. Then, the reliability of the reproduction signal is lowered when the signal has been reproduced by the information reproducing apparatus shown in FIG. 11. In contrast, the second application example in the present embodiment is featured in that a material of which the maximum absorption wavelength does not change between before and after recorded (between the recording mark and the unrecorded area). Therefore, a fluctuation of values of the absorbance "A" after recorded (in recording mark) is suppressed and a fluctuation between the individuals of the reproduction signal amplitude from the above value fluctuation is reduced, whereby the reliability of the reproduction signal has been improved. In this second application example, the maximum absorption wavelength does not change between before and after recording (in recording mark and in unrecorded area), and the value of the absorbance "A" is determined depending on only the spread of the light absorption spectra before and after recording (in recording mark and in unrecorded area). When a large number of write-once type information storage mediums 12 have been mass-produced, it is sufficient if only the spread of the light absorption spectra before and after recorded (in recording mark and in unrecorded area) is controlled, and thus, a fluctuation in characteristics between mediums can be reduced. Even if a contrivance is made so that a maximum absorption wavelength before and after recording (in recording mark and in unrecorded area) does not change, strictly, it is difficult to completely match the values of A,bmax write anc-amax write other, as shown in FIG. 68. The half value width Was of the light absorption spectra around Xbmax write shown in FIG. 65 or 66 is often included in the range of 100 nm to 200 nm in a general organic dye recording material. Therefore, if the value of the maximum absorption wavelength change amount AXmax exceeds 100 nm, it is possible to easily predict from FIG. 65 or 66 that there occurs a large difference between the absorbance Ah4Q5 (A14Q5) obtained from the characteristics of item (b) and the absorption A4Q5 obtained from the characteristics of item (c). Accordingly, the fact that "the maximum absorption wavelength does not change" as the second application example mans that the following condition is met: AA,max Further, when a condition that the maximum absorption wavelength change amount AXmax is 1/3 of the value obtained by formula (50), i.e., AXmax a difference between the absorbance Ah4Q5 (A14Q5) obtained from the characteristics of item (b) and the absorption A4Q5 obtained from the characteristics of item (c) is very small, and a fluctuation in reproduction signal characteristics between the mediums can be reduced. FIG. 68 shows the "L-H" recording film characteristics, which meet formula (50) or formula (51). The light absorption spectra before recorded (in unrecorded area) are obtained as wide spectra as shown in the characteristic (b) of FIG. 68, and the absorbance Ah4Q5 at a reproduction wavelength of 405 nm is obtained as a sufficient small value. The absorbance Ah405 after recorded (in recording mark) narrows in width as shown in the characteristic (a) of FIG. 68, and the absorbance AlQS at a reproduction wavelength of 405 nm rises. In order to meet formula (50) or formula (51), the present embodiment utilizes an "orientation change in molecules" in item [a] of "3-2-B] Basic characteristics common to organic dye recording material in the invention" as a principle of recording. In the azo metal complex shown in FIG. 3, a plurality of benzene nucleus rings are located on the same plane because the benzene nucleus rings are radically coupled with each other. That is, in FIG. 3, four benzene nuclear rings which exist more upwardly than the center metal M forms an U (up-side) plane which the benzene nucleus group produced; and four benzene nuclear rings which exist more downwardly than the center metal M forms a D (down-side) plane which the benzene nucleus group produced. A mutually parallel relationship is always maintained between the above U plane and D plane in any case (irrespective of whether pre-recording or postrecording may be). Side chain groups of Rl and R3 are arranged in a form orthogonal to the above U plane and D plane. Ion coupling is carried out between the center metal atom M and the oxygen atom 0, and a plane formed by a line segment for connecting 0-M-O is located in parallel to the above U plane and D plane. The light emitting area 8 surrounded in a round area shown in FIG. 3 has such a three-dimensional structure. For further description, a direction oriented from a direction of R4 to a direction of R5 in the U plane is tentatively defined as a "Yu direction", and a direction oriented from a direction of R4 to a direction of R5 in the D plane is defined as a "Yd direction". Orientation coupling is carried out between a nitrogen atom N included in the U plane or D plane and the center metal atom M sandwiched between these two planes so that a position of the nitrogen atom N around the center metal atom M can be rotated. That is, a structure is provided such that the Yd direction can be rotated with respect to the Yu direction while a mutually parallel relationship is maintained between the above U plane and D plane. In the azo metal complex shown in FIG. 3, the Yu direction and Yd direction can be parallel to each other, as shown in FIG. 67A (the orientations can be made identical or opposite to each other as shown in FIG. 67A); and the Yu direction and Yd direction can be in a skew position relationship as shown in FIG. 67B. Of course, an arbitrary angle relationship between FIGS. 67A and 67B can be also established. As described previously, the side chain groups of Rl and R3 are arranged in a form orthogonal to the above U plane and D plane. Thus, in the structure of FIG. 67A, collision is likely to occur between the side chain group of Rl or R3 and another side chain group of R4 or the like. Therefore, as shown in FIG. 67B, a time point at which the Yu direction and Yd direction are in a skew position relationship (when the U plane is seen from far above, the Yu direction and Yd direction are seen as if it were orthogonal to each other) is the most stable in a structural point of view. The light absorption wavelength in the light emitting area 8 when the state shown in FIG. 67B is established coincides with a value of Xamax write = ^bmax write shown in FIG. 68. If the relationship between the Yu direction and Yd direction deviates from the state shown in FIG. 67B, the electron structure in the light emitting area 8 and the local distance of light absorption electrons (the size of local area) slightly change, and the light absorption wavelength deviates from the value of amax write = bmax write- BY means of spinner coating, a relationship between the above Yu direction and Yd direction is arbitrarily oriented in the recording layer 3-2 (in unrecorded state) immediately after formed on the transparent substrate 2-2. Therefore, the distribution width of light absorption spectra widens as shown in characteristic (b) of FIG. 68. In order to form a recording mark, when a temperature in the recording layer 3-2 is locally risen, a molecular orientation moves because of a high temperature, and finally, an almost stable state shown in FIG. 67B is established in a structural point of view. Then, the electron structures in the light emitting area 8 coincide with each other anywhere in the recording mark, and the current spectra changes to narrow light absorption spectra in width, as shown in characteristic (a) of FIG. 68. As a result, the absorbance at a reproduction wavelength (for example, 405 nm) changes from Al^QS to Ah4Q5- A description will be made with respect another advantageous effect of using the light emitting area 8 in an azo metal complex. A dye is utilized for a cation portion in the case of utilizing a combination of the anion portion and the cation portion described previously. Although the chromogenic area in each of the dyes shown in FIGS. 27 to 29 occupies a portion in each of the dye structures, a relative occupying capacitance of the chromogenic area in the recording layer 3-2 is decreased by combining this area with an anion portion which does not contribute to the chromogenic area. Therefore, a light absorption sectional area is relatively lowered, and a molar molecule light absorption coefficient is lowered. As a result, a value of the absorbance at a position of A,max write shown in FIG. 25 is reduced, and recording sensitivity is lowered. In contrast, in the case of utilizing the chromogenic characteristics at the periphery of the center metal of an azo metal complex itself described here, the azo metal complex itself emits light, and thus, there does not exist a redundant portion which does not contribute to a chromogenic area such as the anion portion described previously. Therefore, there is no unnecessary factor that the relative occupying capacitance of the chromogenic area decreases. Further, as shown in FIG. 3, the occupying capacitance of the light emitting area 8 in the azo metal complex is wide, and thus, the light absorption sectional area increases, and a value of the molar molecule light absorption coefficient rises. As a result, there is provided advantageous effect that the value of the absorbance at a position of Xmax write shown in FIG. 25 increases, and the recording sensitivity is improved. The present embodiment is featured in that the structural stability of the chromogenic area has been achieved by optimizing the center metal of the azo metal complex as a specific method for "8] stabilizing an electron structure in a chromogenic area so that structural decomposition relevant to ultraviolet ray or reproduction light irradiation hardly occurs" described in "3-2-B] Basic characteristics common to organic dye recording material in the invention". It is known that metal ions have their unique ionization tendency. These metal atoms are arranged in stronger order of ionization tendency, i.e., Na > Mg > Al > Zn > Fe > Ni > Cu > Hg > Ag > Au. The ionization tendency of the metal atoms represents "nature of metal radiating electrons to form positive ions". After a variety of metal atoms has been incorporated as the center metal of the azo metal complex having the structure shown in FIG. 3, where reproduction stability (stability of chromogenic characteristics when a light beam in the vicinity of 405 nm is repeatedly irradiated with reproduction power) is repeatedly checked, it has been found that the metal atoms with high ionization tendency radiates electrons more remarkably and are easily decoupled; and the light emitting area 8 is easily destroyed. As a result of a number of tests, in order to ensure structural stabilization of the chromogenic area, it has been found desirable to use a metal material (Ni, Cu, Hg, Ag, Au) after nickel (Ni) as the center metal. Further, from the viewpoint of "structural stability of high chromogenic area", "low price", and "use safety", it is the most desirable to use copper (Cu) as the center metal as the present embodiment. In the present embodiment, any of CH3, CxHy, H, Cl, F, NC>2, S02, and S02NHCH3 is used as Rl, R2, R3, R4, or R5 which is a side chain shown in FIG. 3. Now, a description will be given with respect to a method for forming an organic dye recording material having a molecular structure shown in FIG. 3 as the recording layer 3-2 on a transparent substrate 2-2. The powdered organic dye recording material of 1.49 g is dissolved in 100 nm of TFP (tetrafluoro propanol) which is a fluorine alcohol based solvent. The above numeric value denotes that 1.4 wt% is obtained as a mixture ratio, and an actual use amount changes depending on a manufacture amount of the write-once type information storage medium. It is desirable that the mixture ratio ranges from 1.2 wt% to 1.5 wt%. As a solvent, it is conditionally mandatory that a surface of the transparent substrate 2-2 made of a polycarbonate resin is not dissolved, and the above described alcohol based solvent is used. Because the above TFP (tetrafluoro propanol) has polarity, the solubility of the powdered organic dye recording material is improved. While the transparent substrate 2-2 on a spindle motor is rotated, the organic dye recording material dissolved in the solvent is applied to the center part of the transparent substrate 2-2 until the solvent has evaporated after the material has been spread by utilizing a centrifugal force, and then, the recording layer 3-2 is compressed in accordance with a baking process for increasing the entire temperature. FIG. 69 shows a third application example in which a basic principle of the second application example in the present embodiment is applied to the "H-L" recording film. The maximum absorption wavelength amax write °f absorption spectra (a) after recorded (in recording mark) is equalized with respect to the maximum absorption wavelength A,bmax Write °f absorption spectra (b) before recorded (in unrecorded area). As an example of a specific organic dye material which achieves the third application example, an azo metal complex is used for an anion portion. For a cation portion, there is used an "anion/cation type organic dye recording material" utilizing dye molecules having an absorption wavelength A,bmax write on a shorter wavelength side than a reproduction signal wavelength (for example, 405 nm), as shown in FIG. 69. In this case, in the azo metal complex shown in FIG. 3, at an a position or a y position in the D plane, which a benzene nucleus group produces and a P position or a 8 position in the U plane which a benzene nucleus group produces, color dye molecules (positively charged cation portion) are allocated by an inter-ion force. As in the second application example, a principle of changing (recording) the light absorption spectra before and after recorded while keeping unchanged the maximum absorption wavelength A,bmax write °f the light absorption spectra (b) before recorded (in unrecorded area) and the maximum absorption wavelength A,amax Write of the light absorption spectra (a) after recorded (in recording mark) utilizes rotation between the U plane (Yu direction) which the benzene nucleus group produces and the D plane (Yd direction) which the benzene nucleus group produces. Further, in the third application example, the electron coupling force in the light emitting area 8 is improved, whereby "degradation of an electron structure (electron orbit) with respect to electrons which contribute to a chromogenic phenomenon" hardly occurs. As a result, an area in the absorption spectra (b) before recorded (in unrecorded area) (an integration result in spectra wavelength direction) can be adjusted to conform to an area in the absorption spectra (a) after recorded (in receding mark). In this manner, the absorbance "A" at the maximum absorption wavelength A,amax write in tne absorption spectra (a) after recorded (in recording mark) becomes greater than the absorbance "1" at the maximum absorption wavelength ?ibmax wrj_te before recorded (in unrecorded area), and a value of A14Q5 rises more significantly than a value of Ah4Q5, as shown in FIG. 69. In the case where degradation in the light emitting area 8 such as discoloring action does not occur, the area in the absorption spectra before and after recorded (the integration result in the spectra wavelength direction) is kept unchanged. Thus, the absorbance Aamax in the maximum absorption wavelength amax write increases with a decrease in the width of the absorption spectra before and after recorded. When a difference clearly occurs between the value of the absorbance Al^gs and the value of Ah4Q5 at the reproduction wavelength of 405 nm (when a reproduction signal can be detected at a good C/N ratio), from FIG. 69, it is found necessary to meet a condition that the value of the absorbance Aamax in the maximum absorption wavelength Xamax write ^s: Aamax 1-2 (52) Further, in order to stably ensure the reliability of reproduction of a detection signal, it is necessary to meet a condition: Aamax > 1.5 (53) Although there has been shown an example of providing a structure in which an azo metal complex is utilized for an anion portion and dyes are utilized for a cation portion as a specific organic dye recording material which achieve the third application example, the invention (third application example) include an organic dye recording material having "H-L" recording characteristics; meeting formula (50) or formula (51) with respect to the maximum absorption wavelength change amount before and after recorded; and changing the absorbance at the maximum absorbance wavelength without being limited thereto, as the specific organic dye recording material which achieves the third application example. Further, a fourth application example is shown in FIG. 70. In a phase change recording film, "atoms are allocated in order (in crystalline state) before recorded", and "atoms are arranged in random (in amorphous state) after recorded". In the fourth application example, a feature of this phase change recording film is combined with a feature that "the maximum absorption wavelength does not change before and after recorded" shown in the second application example. Although a specific organic dye recording material in the fourth application example has a structure of utilizing the azo metal complex shown in the third application example for an anion portion and dyes for a cation portion as a specific organic recording material in the fourth application example, the detailed contained atoms, these application examples are different from each other in terms of detailed contained atoms, detailed intra-molecular structure, or a method for manufacturing the recording layer 3-2. That is, a time required for solidification of the recording layer 3-2 is taken by using an organic solvent which hardly evaporates after applying an organic dye recording material dissolved in an organic solvent on the transparent substrate 2-2 by spinner coating, or alternatively, a temperature of the transparent substrate 2-2 is increased in advance at the time of the application, and then, the temperature of the transparent substrate 2-2 is slowly decreased at the time of evaporation of an organic solvent, whereby a contrivance is made so that the intra-molecular (or inter-molecular) orientation or array can be easily arranged in order at the stage of the solidification of the recording layer 3-2. As a result, as shown in characteristic (b) of FIG. 70, the width of the light absorption spectra before recorded (in unrecorded area) becomes narrow. Next, contrivance is made to apply a recording pulse at the time of recording (for example, after the inside of the recording layer 3-2 has locally exceeded an optical characteristic change temperature, the width of the recording pulse is narrowed instead of increasing the height of the recording pulse at the time of applying the same energy so as to provide rapid cooling), and the intra-molecular (or inter-molecular) orientation or array after recorded (in recording mark) is arranged in random. As a result, the width of the light absorption spectra after recorded (in recording mark) widens as shown in characteristic (a) of FIG. 70. A large difference in absorbance "A" before and after recorded is produced by adjusting a reproduction light wavelength to conform to a lower end position of the light absorption spectra. Although an example of providing a structure in which an azo metal complex is utilized for an anion portion and dyes are utilized for a cation portion as a specific organic dye recording material which achieve the fourth application example, the invention (fourth application example) include an organic dye recording material having "H-L" recording characteristics; meeting formula (50) or formula (51) with respect to the maximum absorption wavelength change amount before and after recorded; and changing the absorbance at the maximum absorbance wavelength without being limited thereto, as the specific organic dye recording material which achieves the fourth application example. Chapter 6: Description Relating to Pre-groove shape/pre-pit shape in coating type organic dye recording film and on light reflection layer interface 6-1) Light reflection layer As described in "Chapter 0: Description of Relationship between Use Wavelength and the Present Embodiment", the present embodiment assumes a range of 355 nm to 455 nm in particular around 405 ran. When the metal materials each having a high light reflection factor at this wavelength bandwidth are arranged in order from the highest light reflection factor, Ag is in the order of around 96%; Al is in the order of around 80%, and Rh is in the order of around 80%. In a write-one type information storage medium using an organic dye recording material, as shown in FIG. 2B, the reflection light from the light reflection layer 4-2 is a standard, and thus, the light reflection layer 4-2 requires a high light reflection factor in characteristics. In particular, in the case of the "HL" recording film according to the present embodiment, the light reflection factor in an unrecorded area is low. Thus, if the light reflection factor in the light reflection layer 4-2 simplex is low, in particular, a reproduction signal C/N ratio from a pre-pit (emboss) area is low, lacking the stability at the time of reproduction. Thus, in particular, it is mandatory that the light reflection factor in the light reflection layer 4-2 simplex is high. Therefore, in the present embodiment, in the above wavelength bandwidth, a material mainly made of Ag (silver) having the highest reflection factor is used. As a material for the light reflection layer 4-2, there occurs a problem that "atoms easily move" or "corrosion easily occurs" if silver is used alone. To solve the first problem, when partial alloying is carried out by adding other atoms, silver atoms hardly move. In the first embodiment in which other atoms are added, the light reflection layer 4-2 is made of AgNdCu according to the first embodiment. AgNdCu is in a solid soluble state, and thus, the reflection factor is slightly lowered than a state in which silver is used alone. In the second embodiment in which other atoms are added, the light reflection layer 4-2 is made of AgPd, and an electric potential is changed, whereby corrosion hardly occurs in an electrochemical manner. If the light reflection layer 4-2 corrodes due to silver oxidization or the like, the light reflection factor is lowered. In an organic dye recording film having a recording film structure shown in FIG. 2B, in particular, in the case of an organic dye recording film shown in "Chapter 3: Description of Characteristics of Organic Dye Recording Film in the Present Embodiment", in particular, a light reflection factor on an interface between the recording layer 3-2 and the light reflection later 4-2 is very important. If correction occurs on this interface, the light reflection factor is lowered, and an optical interface shape blurs. In addition, the detection signal characteristics from a track shift detection signal (push-pull signal) or a wobble signal and a pre-pit (emboss) area are degraded. In addition, in the case where the width Wg of the pregroove area 11 is wider than the width Wl of the land area, a track shift detection signal (push-pull signal) or a wobble signal is hardly generated, thus increasing effect of degradation of the light reflection factor on the interface between the recording layer 3-2 and the light reflection layer 4-2 due to corrosion. In order to prevent degradation of the light reflection factor on this interface, AgBi is used for the light reflection layer 4-2 as the third embodiment. AgBi forms a very stable phase and prevents degradation of the light reflection factor on the above interface because a passive coat film is formed on a surface (interface between the recording layer 3-2 and the light reflection layer 4-2). That is, if Bi (bismuth) is slightly added to Ag, Bi is isolated from the above interface, the isolated Bi is oxidized. Then, a very fine film (passive coat film) called oxidized bismuth is formed to function to preclude internal oxidization. This passive coat film is formed on the interface, and forms a very stable phase. Thus, the degradation of a light reflection factor does not occur, and the stability of detection signal characteristics from a track shift detection signal (push-pull signal) or a wobble signal and a pre-pit (emboss) area is guaranteed over a long period of time. At a wavelength band ranging from 355 nm to 455 nm, the silver simplex has the highest light reflection factor, and the light reflection factor is lowered as an additive amount of other atoms is increased. Thus, it is desirable that an additive amount of Bi atoms in AgBi in the present embodiment be equal to or smaller than 5 at%. The unit of at% used here denotes atomic percent, and indicates that five Bi atoms exist in a total atom number 100 of AgBi, for example. When characteristics have been evaluated by actually producing the passive coat film, it has found that a passive coat film can be produced as long as an additive amount of Bi atoms is equal to or greater than 0.5 at%. Based on a result of this evaluation, an additive amount of Bi atoms in the light reflection layer 4-2 in the present embodiment is defined as 1 at%. In this third embodiment, only one atom Bi is added, and an additive amount of atoms can be reduced as compared with AgNdCu according to the first embodiment (a case in which two types of atoms Nd and Cu is added in Ag), and AgBi can increase the light reflection factor more significantly than AgNdCu. As a result, even in the case of the "H-L" recording film according to the present embodiment or in the case where the width Wg of the pre-groove area 11 is wider than the with Wl of the land area, as shown in FIGS. 8B and 8C, a detection signal can be stably obtained from a track shift detection signal (push-pull signal) or a wobble signal and a pre-pit (emboss) area with high precision. The third embodiment is not limited to AgBi, and a ternary system including AgMg, AgNi, AgGa, AgNx, AgCo, AgAl or the atoms described previously may be used as a silver allow which produces a passive coat film. The thickness of this light reflection layer 4-2 is set in the range of 5 nm to 200 nm. If the thickness is smaller than 5 nm, the light reflection layer 4-2 is not uniform, and is formed in a land shape. Therefore, the thickness of the light reflection layer 4-2 is set to 5 nm. When an AgBi film is equal to or smaller than 80 nm in thickness, the film permeates to its back side. Thus, in the case of a one-sided single recording layer, the thickness is set in the range of 80 nm to 200 nm, and preferably, in the range of 100 nm to 150 nm. In the case of a onesided double recording layer, the thickness is set in the range of 5 nm to 15 nm. Write-once type information storage mediums having high density and used for a method for recording information in a storage medium which uses an organic dye material, the storage mediums carrying out recording and reproduction by using a light beam of 620 nm or less in wavelength, include: a one-sided single-layer medium as shown in FIG. IB; and a onesided double-layer medium as shown in FIG. 1C. The one-sided single-layer medium is sequentially composed of a transparent substrate 2-2, a recording layer (recording film) 3-2, and a light reflection layer (light reflection film) 4-2 from a light incident side. A storage medium (referred to as LO) close to the light incident side of the one-sided double-layer medium is sequentially composed of the transparent substrate 2-2, the recording layer 3-2, and a semipermeable light reflection layer 4-2 from the light incident side. A storage medium (referred to as LI) distant from the light incident side is sequentially composed of the recording layer 3-2, the light reflection layer 4-2, and the substrate 2-2 from the light incident side. A layer for optically separating two layers, a so called interlayer separating layer (interlayer separation film) 7-1, is formed between the medium LO and the medium LI. In addition, the transparent substrate 2-2 of the medium LI may not be always transparent, and an opaque substrate may be used. In the following description, in the case where a layer is merely referred to as a light reflection layer, it denotes a generic name of the light reflection layer 4-1 and the semipermeable light reflection layer 4-2. In order to obtain high signal characteristics on an entire surface of an optical storage medium, there is a need for providing a high reflectivity in a state in which the transparent substrate 2-2, the recording layer 3-2, and the light reflection layer 4-2 have been laminated. Thus, it is desirable that a light reflection film simplex have a high reflectivity. In order to achieve this, a material mainly made of Ag (silver) having the highest reflectivity is used in the above wavelength band (405 nm and its proximity, for example, 355 nm to 455 nm). On the other hand, as described in section 6-1), in a silver simplex used as a material for a light reflection film, there occurs a problem that light reflection characteristics are changed by the fact that "atoms easily move" and "corrosion easily occurs", and the performance is degraded in terms of information repetition reproduction, count, and storage service life. As a means for solving these problems, a method using a variety of silver alloys is conventionally known. However, in the storage medium according to the present invention, there is used an organic dye recording material which has not been used conventionally. Thus, in the conventional method, the above-described problems have not been solved. A conventionally known method for preventing movement of single silver atoms in a light reflection film includes a method for adding to silver an element which has a pinning effect. On the other hand, there has not been clarified an element which prevents movement of single silver atoms without lowering a reflectivity in the above-described wavelength band or significantly lowering thermal characteristics. With respect to a disclosed conventional technique, as long as an amount of additives is not particularly large, there is substantially no advantageous effect. On the other hand, there are two methods for preventing corrosion of silver in a reflection film; (1) a electrochemical method; and (2) a method for forming a passive coat on an interface. With respect to (1) the electrochemical method, as long as an amount of additives is not particularly large, there is substantially no advantageous effect. In addition, with respect to (2) the method for forming the passive coat on the interface as well, there has not been achieved a method for forming a rigid passive coat without lowering the reflectivity in the abovedescribed wavelength band or significantly lowering the thermal characteristics. This is because, in order to complete a storage medium embodiment, characteristics greatly depend on what configuration of a storage medium is used, and thus, it is impossible to obtain problems to be solved and a proper means for solving these problems merely by investigating general material characteristics. In addition, in the case of the present embodiment, in addition to these problems, it has been difficult to achieve the embodiment by the use of the organic dye recording material which has not been used conventionally, as described below. In order to prevent movement of single silver atoms and prevent corrosion of silver in a reflection film without lowering the reflectivity in the abovedescribed waveform band or without significantly lowering the thermal characteristics, the present embodiment is featured by a light reflection layer of a storage medium shown in FIGS. IB and 1C using an organic dye material recorded with a light beam of 620 nm or less in wavelength in which prevention layers 8, 8-1, and 8-2 which prevent a characteristic change of a light reflection layer are provided between a light reflection layer and a recording layer. The causes for characteristic change are movement of atoms and reaction (corrosion). The reaction used here includes a chemical reaction or performance degradation caused by a light reflection layer coming into contact with an organic dye material which is a recording film. The prevention layer used here may not be formed to have a finite thickness (passive coat formed on interface), and may be formed as a layer (electrochemical layer) having electrically different characteristics, the layer being formed by a semiconductor apparatus or a semiconductor device and the like. The light reflection layer used here is composed essentially of silver Ag, contains at least one type of additive elements selected from: aluminum Al; gold Au; bismuth Bi; calcium Ca; cerium Ce, cobalt Co, gallium Ga, lanthanum La; magnesium Mg; nitrogen N; nickel Ni; neodium Nd; palladium Pd; yttrium Y; tungsten W, and zirconium Zr, and ranges from 0.05 at% to 5 at% in total of additive elements. It is impossible to avoid entry of a very small amount of elements into Ag and additive elements used as a base material for a reflection film material. With respect to these elements, even if a very small amount thereof is detected by analysis, it is impossible to say they are a different material. Therefore, this material is not said to be different from the scope of the present invention. For example, let us consider a light reflection layer using AgBi. AgBi forms a passive coat on a surface (interface between recording layer 3-2 and light reflection layer 4-2). Thus, this element forms a very high stable phase, and prevents degradation of the light reflectivity on the above-described interface. That is, if a small amount of Bi (bismuth) is added to Ag, Bi floats on the interface, and is oxidized. Then, a very delicate film (passive coat) called bismuth oxide is formed, and functions to stop internal oxidization or reaction, or alternatively, degradation of the reflection film. In addition, in a combination with the organic dye recording material used in the present embodiment, it has been found that there is attained advantageous effect of preventing movement of single silver atoms without lowering the reflectivity in the above-described wavelength band or significantly lowering the thermal characteristics. In general, the concentration of additive elements in an Ag alloy is greatly influenced by a reflectivity or optical characteristics, thermal characteristics, and easiness of movement of single silver atoms. Therefore, an Ag alloy in which a concentration change occurs is considered to be generally low in advantageous effect of preventing movement of single silver atoms without lowering the reflectivity or significantly lowering the thermal characteristics. In the present embodiment, it is considered that advantageous effect has been attained in a configuration which seems to have been ineffective conventionally because a specific organic dye material is used. Therefore, the present invention is greatly featured by a light reflection layer of a storage medium using an organic dye material recorded with a light beam of 620 nm or less in wavelength in which there is formed a prevention layer which prevents reaction between a light reflection layer and a recording layer caused by the light reflection layer coming into contact with an organic dye material or a characteristic change or degradation of an optical reflection layer. These advantageous effects are considered as being attained by combining the organic dye material and the Ag alloy according to the present embodiment. In addition, apart from Bi, it has been found that similar advantageous effect is attained in Ca, Ce, Co, Ga, Ni, La, Mg, W, and Zr (elements for forming a passive coat including Bi is referred to as additive elements of group 1). On the other hand, in Al, Au, Pd, Pt, and Rh (referred to as additive elements of group 2), electrochemically advantageous effect is strong. Thus, it is effective to use these additive elements of group 2 in combination with the additive elements of group 1. In addition, with respect to N (nitrogen), a reaction product with Ag-N serves as part of a passive coat. Thus, the passive coat may be formed of a plurality of layers without being limited to a single layer. In addition to the additive elements of group 1, it is effective to add Cu, Nd, or Y (referred to as additive elements of group 3). With respect to group 2, group 3, and N, even if comparatively large amounts of these elements are added or reacted, no precipitation occurs, and solid solution or reaction with Ag can be obtained. Thus, if an amount of additives increases, the reflectivity or thermal conductivity is rapidly lowered. Therefore, careful consideration is required for the amount of additives and adding process. Among them, for example, in the case where AgAl is used, if an amount of additives increases, the lowering of the reflectivity and thermal conductivity of the reflection film becomes very substantial. When the content of additive elements 0.05 at% or less, advantageous effect is low. In addition, when it is 5 at% or more, advantageous effect is low. In the case where an amount of additive elements is 0.05 at% or less, in particular, performance of forming a passive coat and preventing corrosion is lowered. Conversely, in the case where an amount of additive elements is 5 at% or more, the lowering of the reflectivity and thermal characteristics becomes substantial. The above-described amount of additive elements denotes an amount analyzed by forming a reflection film simplex on a substrate on which no reaction occurs or a substrate composed of elements separated by analysis even if a reaction occurs. Therefore, in the storage medium, the additive elements move from the inside of the reflection film onto an interface of an organic dye material and the like, thereby forming a passive coat, and thus, locally different portions may exist. Therefore, an amount of additive elements indicates a value obtained by analyzing an amount added to the reflection layer without forming a passive coat. With respect to the concentration of the additive elements in the reflection layer, the additive elements occasionally move onto an interface with an opposite adhesive layer in addition to moving onto the interface with the organic dye recording material which is a recording layer, thereby forming a passive coat. To which interface a larger amount of the elements move depends on type of organic dye recording material to be used, Ag alloy of reflection layer to be used and type of adhesive to be used. 6-2) Description relating to pre-pit shape in coating type organic dye recording film and on light reflection layer interface In an H format according to the present embodiment, as shown in FIGS. 35A, 35B and 35C, the system lead-in area SYLDI is provided. In this area, an emboss pit area 211 is provided, and, as shown in FIGS. 71A and 71B, information is recorded in advance in the form of a pre-bit. A reproduction signal in this area is adjusted to conform to reproduction signal characteristics from a read-only type information storage medium, and a signal processor circuit in an information reproducing apparatus or an information recording/reproducing apparatus shown in FIG. 11 is compatible with a read-only type information storage medium and a write-once type information storage medium. A definition relevant to a signal detected from this area is adjusted to conform with a definition of "3-4): Description of characteristics relating to "H-L" recording film in the invention". That is, a reproduction signal amount from the space area 14 having a sufficiently large length (11T) is defined as IllHf and a reproduction signal from the pre-pit (emboss) area 13 having a sufficiently large length (11T) is defined as IHL- In addition, a differential value between these amounts is defined as !]_]_ = IHH ~ IHL- n the present embodiment, in accordance with the reproduction signal characteristics from the read-only type information storage medium, the reproduction signal in this area is set to be: Ill/Inn 0.3 (54) and desirably, is set to be: I11/I11H > O-5 (55) When a repetitive signal amplitude of the space area 14 relevant to the pre-pit (emboss) area 13 having a 2t length is defined as 12, the amplitude is set to be: I2/In > 0.5 (56) and desirably, is set to be: I2/In > 0.7 (57) A description will be given with respect to a physical condition for meeting the above formula (54) or formula (55). As has been described in FIG. 2B, the signal characteristics from a pre-pit are mainly dependent on the reflection in the light reflection layer 4-2. Therefore, the reproduction signal amplitude value _]_ is determined depending on a step amount Hpr between the space area 14 and the pre-pit (emboss) area 13 in the light reflection layer 4-2. When optical approximation calculation is made, this step amount Hpr, with respect to a reproduction light wavelength A, and a refractive index n32 in tne recording layer 3-2, has the following relationship: 111 « sin2{(27i x Hpr x n32)/M (58) From formula (58), it is found that In becomes maximal when Hpr ^ X/(4 x n32). In order to meet formula (54) or formula (55), from formula (58), it is necessary to meet: Hpr > K/ (12 x n32) (59) and desirably, Hpr > A,/(6 x n32) (60) As described in "Chapter 0: Description of Relationship between Use Wavelength and the Present Embodiment", X = 355 nm to 455 nm is used in the embodiment, and as described in "2-1) Difference in Principle of Recording/Recording Film and Difference in Basic Concept Relating to Generation of Reproduction Signal", n32 = 1.4 to 1.9 is established. Thus, when this value is substituted into formula (59) or formula (60), a step is produced so as to meet a condition: Hpr > 15.6 nm (62) and desirably, Hpr > 31.1 nm (63) In the conventional write-once type information storage medium, as shown in FIG. 71B, the thickness of the recording layer 3-2 is small in the space area 14, and thus, a step on an interface between the light reflection layer 4-2 and the recording layer 3-2 is small, and formula (62) has not successfully met. In contrast, in the present embodiment, a contrivance has been made to ensure that a relationship between the thickness Dg of the recording layer 3-2 in the pre-pit (emboss) area 13 and the thickness Dl of the recording layer 3-2 in the space area 14 conform with a condition described in "3-2-E] Basic characteristics relating to thickness distribution of recording layer in the present embodiment for definition of parameters". As a result, as shown in FIG. 71B, a sufficiently large step Hpr which meets formula (62) or formula (63) has been successfully provided. By carrying out optical approximation discussion as described above, in the present embodiment, in order to have sufficient resolution of a reproduction signal so as to meet formula (56) or formula (57), a contrivance is made so that the width Wp of the pre-pit (emboss) area 13 is equal to or smaller than half of track pitches as shown in FIG. 71B, and a reproduction signal from the pre-pit (emboss) area 13 can be largely taken. 6-3) Description relating to pre-groove shape in coating type organic dye recording film and on light reflection layer interface: Chapter 7: Description of H Format Now, an H format in the present embodiment will be described here. FIG. 31 shows a structure and dimensions of an information storage medium in the present embodiment. As embodiments, there are explicitly shown three types of embodiments of information storage mediums such as: - "read-only type information storage medium" used exclusively for reproduction in which recording cannot be carried out; - "write-once type information storage medium" capable of additional recording; and - "rewritable type information storage medium" capable of rewriting or recording any times As shown in FIG. 31, the above three types of information storage mediums are common to each other in a majority of structure and dimensions. In all of the three types of information storage mediums, from their inner periphery side, a burst cutting area BCA, a system lead-in area SYLDI, a connection area CNA, a data lead-in area DTLSI, and a data area DTA have been arranged. All the mediums other than an OPT type readonly medium is featured in that a data lead-out area DTLDO is arranged at the outer periphery. As described later, in the OPT type read-only medium, a middle area MDA is arranged at the outer periphery. In either of the write-once type and rewritable type mediums, the inside of this area is for read-only (additional writing disabled). In the read-only type information storage medium, information is recorded in the data lead-in area DTLDI in the form of emboss (pre-pit). In contrast, in the write-once type and the rewritable type information storage medium, new information can be additionally written (rewritten in the rewritable type) by forming a recording mark in the data lead-in area DTLDI. As described later, in the write-once type and rewritable type information storage medium, in the data lead-out area DTLDO, there coexist an area in which additional writing can be carried out (rewriting can be carried out in the rewritable type) and a read-only area in which information is recorded in the form of emboss (pre-pit). As described previously, in the data area DTA, data lead-in area DTLVI, data lead-out area DTSDO, and middle area MDA shown in FIG. 31, high density of the information storage medium is achieved (in particular, line density is improved) by using a PRML (Partial Response Maximum Likelihood) method for reproduction of signals recorded therein. In addition, in the system lead-in area SYLDI and the system leadout area SYLDO, compatibility with a current DVD is realized and the stability of reproduction is improved by using a slice level detecting system for reproduction of signals recorded therein. Unlike the current DVD specification, in the embodiment shown in FIG. 31, the burst cutting area BCA and system lead-in area SYLDI are separated from each other in location without being superimposed on each other. These areas are physically separated from each other, thereby making it possible to prevent interference between the information recorded in the system lead-in area SYLDI at the time of information reproduction and the information recorded in the burst cutting area BCA and to allocate information reproduction with high precision. In the case where an "L-H" type recording film has been used as another embodiment, there is a method for forming fine irregularities in advance in location for allocating the burst cutting area BCA. A description will be given later with respect to information on polarity (identification of "H-L" or "L-H") of a recording mark which exists at a 192nd byte in FIG. 42. In this section, a description will be given with respect to the present embodiment in which an "L-H" recording film as well as the "H-L" recording film is also incorporated in a specification and a scope of selecting the recording film is widened to enable high speed recording or supply of an inexpensive medium. As described later, the present embodiment also considers a case of using the "L-H" recording film. Data recorded in the burst cutting area BCA (barcode data) is formed by locally carrying out laser exposure to a recording film. As shown in FIGS. 35A, 35B and 35C, the system lead-in area SYLDI is formed of the emboss bit area 211, and thus, the reproduction signal from the system lead-in area SYLDI appears in a direction in which a light reflection amount decreases as compared with a light reflection level from the mirror surface 210. If while the burst cutting area BCA is formed as the mirror surface 210, in the case where the "L-H" recording film has been used, a reproduction signal from the data recorded in the burst cutting area BCA appears in a direction in which a light reflection amount increases more significantly than a light reflection level from the mirror surface 210 (in an unrecorded state). As a result, a significant step occurs between a position (amplitude level) of a maximum level and a minimum level of the reproduction signal from the data recorded in the burst cutting area BCA and a position (amplitude level) of a maximum level and a minimum level of the reproduction signal from the system lead-in area SYLDI. As described later with respect to FIGS. 35A, 35B and 35C, an information reproducing apparatus or an information recording/reproducing apparatus carry out processing in accordance with the steps of: 1) reproducing information in the burst cutting area BCA; 2) reproducing information contained in a information data zone CDZ in the system lead-in area SYLDI; 3) reproducing information contained in the data lead-in area DTLDI (in the case of write-once type or rewriting type); 4) readjusting (optimizing) a reproduction circuit constant in a reference code recording zone RCZ; and 5) reproducing information recorded in the data area DTA or recording new information. Thus, if there exists a large step between a reproduction signal amplitude level from the data formed in the burst cutting area BCA and a reproduction signal amplitude level from the system lead-in area SYLDI, there occurs a problem that the reliability of information reproduction is lowered. In order to solve this problem, in the case where the "L-H" recording film is used as a recording film, the present embodiment is featured in that fine irregularities are formed in advance in thus burst cutting area BCA. When such fine irregularities are formed, the light reflection level becomes lower than that from the mirror surface 210 due to a light interference effect at the stage prior to recording data (barcode data) by local laser exposure. Then, there is attained an advantageous effect that a step is remarkably decreased between a reproduction signal amplitude level (detection level) from the data formed in the burst cutting area BCA and a reproduction signal amplitude level (detection level) from the system lead-in area SYLDI; the reliability of information reproduction is improved; and processing going from the above item 1) to item 2) is facilitated. In the case of using the "L-H" recording film, the specific contents of fine irregularities formed in advance in the burst cutting area BCA include the emboss pit area 211 like the system lead-in area SYLDI. Another embodiment includes a method for forming the groove area 214 or the land area and the groove area 213 like the data lead-in area DTLDI or data area DTA. As has been described in the description of embodiments in which the system lead-in area SYSDI and burst cutting area BCA are separately arranged, if the burst cutting area BCA and the emboss bit area 211 overlaps each other, there increases a noise component from the data provided in the burst cutting area BCA due to unnecessary interference to a reproduction signal. When the groove area 214 or the land area and groove area 213 is formed without forming the emboss pit area 211 as an embodiment of the fine irregularities in the burst cutting area BCA, there is attained an advantageous effect that there decreases a noise component from the data formed in the burst cutting area BCA due to unnecessary interference to a reproduction signal and the quality of a reproduction signal is improved. When track pitches of the groove area 214 or the land area and groove area 213 formed in the burst cutting area BCA are adjusted to conform with the those of the system lead-in area SYLDI, there is attained an advantageous effect that the manufacturing performance of the information storage medium is improved. That is, at the time of original master manufacturing of the information storage medium, emboss pits in the system lead-in area are produced while a feed motor speed is made constant. At this time, the track pitches of the groove area 214 or the land area and groove area 213 formed in the burst cutting area BCA are adjusted to conform with those of the emboss pits in the system lead-in area SYLDI, thereby making it possible to continuously maintain a constant motor speed in the burst cutting area BCA and the system lead-in area SYLDI. Thus, there is no need for changing the speed of the feed motor midway, and thus, the pitch non-uniformity hardly occurs, and the manufacturing performance of the information storage medium is improved. FIG. 32 shows parameter values according to the present embodiment in a read-only type information storage medium; FIG. 33 shows parameter values according to the present embodiment in a write-once type information storage medium; and FIG. 34 shows parameter values according to the present embodiment in a rewritable type information storage medium. As is evident in comparison between FIG. 32 or 33 and FIG. 34 (in particular, in comparison of section (B)), the rewritable type information storage medium has higher recording capacity than the read-only type or write-once type information storage medium by narrowing track pitches and line density (data bit length). As described later, in the rewritable type information storage medium, the track pitches are narrowed by reducing effect of a cross-talk of the adjacent tracks by employing land-groove recording. Alternatively, any of the read-only type information storage medium, write-once information storage medium, and rewritabletype information storage medium is featured in that the data bit length and track pitches (corresponding to recording density) of the system lead-in/system leadout areas SYLDI/SYLDO are greater than those of the data lead-in/data lead-out area DTLDI/DTLDO (in that the recording density is low). The data bit length and track pitches of the system lead-in/system lead-out areas SYLDI/SYLDO are close to the values of the current DVD lead-in area, thereby realizing compatibility with the current DVD. In the present embodiment as well, like the current DVD-R, an emboss step in the system lead-in/system lead-out areas SYLDI/SYLDO of the write-once type information storage medium is shallowly defined. In this manner, there is attained advantageous effect that a depth of a pregroove of the write-once information storage medium is shallowly defined and a degree of modulation of a reproduction signal from a recording mark formed on a pre-groove by additional writing is increased. In contrast, as a counteraction against it, there occurs a problem that the degree of modulation of the reproduction signal from the system lead-in/system lead-out areas SYLDI/SYLDO decreases. In order to solve this problem, the data bit length (and track pitches) of system lead-in/system lead-out areas SYLDI/SYLDO are roughened and a repetition frequency of pits and spaces at the narrowest position is isolated (significantly reduced) from an optical shutdown frequency of an MTF (Modulation Transfer Function) of a reproduction objective lens, thereby making it possible to increase the reproduction signal amplitude from the system lead-in/system lead-out areas SYLDI/SYLDO and to stabilize reproduction. FIGS. 35A, 35B and 35C show a comparison of detailed data structure in a system lead-in area SYLDI and a data lead-in area DTLDI in a variety of information storage mediums. FIG. 35A shows a data structure of a read-only type information storage medium; FIG. 35B shows a data structure of a rewritable-type information storage medium; and FIG. 35C shows a data structure of a write-once type information storage medium. As shown in FIG. 35A, except that only a connection zone CNZ is formed as a mirror surface 210, the read-only type information storage medium is featured in that the emboss pit area 211 having emboss pits formed therein is provided in all of the system lead-in area SYLDI and data lead-in area DTLDI and data area DTA. The emboss pit area 211 is provided in the system lead-in area SYLDI, and the connection zone CNZ is provided in the mirror surface 210. As shown in FIG. 35B, the rewritable-type information storage medium is featured in that the land area and the groove area 213 are formed in the data lead-in area DTLSI and the data area DTA. The write-once type information storage medium is featured in that the groove area 214 is formed in the data lead-in area DTLDI and the data area DTA. Information is recorded by forming a recording mark in the land area and the groove area 213 or groove area 214. The initial zone INZ indicates a start position of the system lead-in area SYLDI. As significant information recorded in the initial zone INZ, there is discretely arranged data ID (Identification Data) information including information on physical sector numbers or logical sector numbers described previously. As described later, one physical sector records information on a data frame structure composed of data ID, IED (ID Error Detection code), main data for recording user information, and EDC (Error detection code); and the initial zone records information on the above described data frame structure. However, in the initial zone INZ, all the information on the main data for recording the user information is all set to "OOh", and thus, the significant information contained in the initial zone INZ is only data ID information. A current location can be recognized from the information on physical sector numbers or logical sector numbers recorded therein. That is, when an information recording/reproducing unit 141 shown in FIG. 11 starts information reproduction from an information storage medium, in the case where reproduction has been started from the information contained in the initial zone INZ, first, the information on physical sector numbers or logical sector numbers recorded in the data ID information is sampled, and the sampled information is moved to the control data, zone CDZ while the current location in the information storage medium is checked. A buffer zone 1 BFZl and a buffer zone 2 BFZ2 each are composed of 32 ECC blocks. As shown in FIGS. 32, 33 and 34, one ECC block corresponds to 1024 physical sectors. In the buffer zone I BFZl and the buffer zone 2 BFZ2 as well, like the initial zone INZ, main data information is set to all "OOh". The connection zone CNZ which exists in a CNA (Connection Area) is an area for physically separating the system lead-in area SYLDI and the data lead-in area DTLDI from each other. This area is provided as a mirror surface on which no emboss pit or pre-groove exists. An RCZ (Reference code zone) of the read-only type information storage medium and the write-once type information storage medium each is an area used for reproduction circuit tuning of a reproducing apparatus (for automatic adjustment of tap coefficient values at the time of adaptive equalization carried out in the tap controller 332 shown in FIG. 15) , wherein information on the data frame structure described previously is recorded. A length of the reference code is one ECC block (= 32 sectors). The present embodiment is featured in that the RCZ (Reference code zone) of the read-only type information storage medium and the write-once information storage medium each is arranged adjacent to a DTA (data area). In any of the structures of the current DVD-ROM disk and the current DVD-R disk as well, a control data zone is arranged between the reference code zone and data area, and the reference code zone and the data area are separated from each other. If the reference code zone and data area are separated from each other, a tilt amount or a light reflection factor of the information storage medium or the recording sensitivity of a recording film (in the case of the write-once information storage medium) slightly changes. Therefore, there occurs a problem that an optimal circuit constant in the data area is distorted even if a circuit constant of the reproducing apparatus is adjusted. In order to solve the above described problem, when the RCZ (reference code zone) is arranged adjacent to the DTA (data area), in the case where the circuit constant of the information reproducing apparatus has been optimized in the RCZ (reference code zone), an optimized state is maintained by the same circuit constant in the DTA (data area). In the case where an attempt is made to precisely reproduce a signal in arbitrary location in the DTA (data area), it becomes possible to reproduce a signal at a target position very precisely in accordance with the steps of: 1) optimizing a circuit constant of the information reproducing apparatus in the RCZ (reference code zone); 2) optimizing a circuit constant of the information reproducing apparatus again while reproducing a portion which is the closest to the reference code zone RCZ in the data area DTA; 3) optimizing a circuit constant once again while reproducing information at an intermediate position between a target position in the data area DTA and the position optimized in step 2); and 4) reproducing signal after moving to the target position. GTZ1 and GTZ2 (guard track zones 1 and 2) existing in the write-once information storage medium and the rewritable-type information storage medium are areas for specifying the start boundary position of the data lead-in area DTLDI, and a boundary position of a drive test zone DRTZ and a disc test zone DKTZ. These areas are prohibited from being recorded a recording mark. The guard track zone 1 GTZ1 and guard track zone 2 GTZ2 exist in the data lead-in area DTLDI, and thus, in this area, the write-once type information storage medium is featured in that the pre-groove area is formed in advance. Alternatively, the rewritable-type information storage medium is featured in that the groove area and the land area are formed in advance. In the pre-groove area or groove area and the land area, as shown in FIGS. 32, 33 and 34, wobble addresses are recorded in advance, and thus, the current location in the information storage medium is determined by using these wobble addresses. The disk test zone DKTZ is an area provided for manufactures of information storage mediums to carry out quality test (evaluation). The drive test zone DRTZ is provided as an area for carrying out test writing before the information recording/reproducing apparatus records information in the information storage medium. The information recording/reproducing apparatus carries out test writing in advance in this area, and identifies an optimal recording condition (write strategy). Then, the information contained in the data area DTA can be recorded under the optimal recording condition. The information recorded in the disk identification zone DIZ which exists in the rewritabletype information storage medium (FIG. 35B) is an optional information recording area, the area being adopted to additionally write a set of drive descriptions composed of: information on manufacturer name of recording/reproducing apparatuses; additional information relating thereto; and an area in which recording can be uniquely carried out by the manufacturers. A defect management area 1 DMA1 and a defect management area 2 DMA2 which exist in a rewritable-type information storage medium (FIG. 35B) record defect management information contained in the data area DTA, and, for example, substitute site information when a defect occurs or the like is recorded. In the write-once type information storage medium (FIG. 35C), there exist uniquely: an RMD duplication zone RDZ; a recording management zone RMZ; and an R physical information zone R-PFIZ. The recording management zone RMZ records RMD (recording management data) which is an item of management information relating to a recording position of data updated by additional writing of data. A detailed description will be given later. As described later in FIGS. 36 (a), (b), (c) and (d), in the present embodiment, a recording management zone RMZ is set for each bordered area BRDA, enabling area expansion of the recording management zone RMZ. As a result, even if the required recording management data RMD increases due to an increase of additional writing frequency, such an increase can be handled by expanding the recording management zone RMZ in series, and thus, there is attained advantageous effect that the additional writing count can be significantly increased. In this case, in the present embodiment, the recording management zone RMZ is arranged in a border-in BRDI which corresponds to each bordered area BRDA (arranged immediately before each bordered area BRDA). In the present embodiment, the border-in BRDI corresponding to the first bordered area BRDA#1 and a data lead-in area DTLDI are made compatible with each other, and efficient use of the data area DTA is promoted while the forming of the first border-in BRDI in the data area DTA is eliminated. That is, the recording management zone RMZ in the data lead-in area DTA shown in FIG. 35C is utilized as a recording location of the recording management data RDM which corresponds to the first bordered area BRDA#1. The RMD duplication zone RDZ is a location for recording information on the recording management data RMD which meets the following condition in the recording management zone RMZ, and the reliability of the recording management data RMD is improved by providing the recording management data RMD in a duplicate manner, as in the present embodiment. That is, in the case where the recording management data RMD contained in the recording management zone RMZ is valid due to dust or scratch adhering to a write-once information storage medium surface, the recording management data RMD is reproduced, the data being recorded in this RMD duplication zone RDZ. Further, the remaining required information is acquired by tracing, whereby information on the latest recording management data RMD can be restored. This RMD duplication zone records recording management data RDM at a time point at which (a plurality of) borders are closed. As described later, a new recording management zone RMZ is defined every time one border is closed and a next new bordered area is set. Thus, every time a new recording management zone RMZ is created, the last recording management data RMD relating to the preceding bordered area may be recorded in this RMD duplication zone RDZ. When the same information is recorded in this RMD duplication zone RDZ every time the recording management data RDM is additionally recorded on a write-once information storage medium, the RMD duplication zone RDZ becomes full with a comparatively small additional recording count, and thus, an upper limit value of the additional writing count becomes small. In contrast, as in the present embodiment, in the case where a recording management zone is newly produced when a border is closed, the recording management zone in the border-in BRDI becomes full, and a new recording management zone RMZ is formed by using an R zone, there is attained advantageous effect that only the last recording management data RMD contained in the past recording management zone RMZ is recorded in the RMD duplication zone RDZ, thereby making it possible to improve an allowable additional writing count by efficiently using the RMD duplication zone RDZ. For example, in the case where the recording management data RMD contained in the recording management zone RMZ which corresponds to the bordered area BRDA on the way of additional writing (before closed) cannot be reproduced due to the dust or scratch adhering to the surface of the write-once type information storage medium, a location of the bordered area BRDA, which has been already closed, can be identified by reading the recording management data RMD lastly recorded in this RMD duplication zone RDZ. Therefore, the location of the bordered area BRDA on the way of additional writing (before closed) and the contents of information recorded therein can be acquired by tracing another location in the data area DTA of the information storage medium, and the information on the latest recording management data RMD can be restored. An R physical information zone R-PFIZ records the information analogous to the physical format PFI contained in the control data zone CDZ which exists common to FIGS. 35A to 35C (described later in detail). FIG. 36 shows a data structure in the RMD duplication zone RDZ and the recording management zone RMZ which exists in the write-once type information storage medium (FIG. 35C). FIG. 36 (a) shows the same structure as that shown in FIG. 35C, and FIG. 36 (b) shows an enlarged view of the RMD duplication zone RDZ and the recording management zone RDZ shown in FIG. 35C. As described above, in the recording management zone RMZ contained in the data lead-in area DTLDI, data relating to recording management which corresponds to the first bordered area BRDA is collectively recorded, respectively, in one items of recording management data (RMD); and new recording management data RMD is sequentially additionally written at the back side every time the contents of the recording management data RMD generated when additional writing process has been carried out in the write-once information storage medium are updated. That is, the RMD (Recording Management Data) is recorded in size units of single physical segment block (a physical segment block will be described later), and new recording management data RMD is sequentially additionally written every time the contents of data are updated. In the example shown in FIG. 36 (b), a change has occurred with management data in location recording management data RMD#1 and RMD#2 has been recorded. Thus, this figure shows an example in which the data after changed (after updated) has been recorded as recording management data RMD#3 immediately after the recording management data RMD#2. Therefore, in the recording management zone RMD, a reserved area 273 exists so that additional writing can be further carried out. Although FIG. 36 (b) shows a structure in the recording management zone RMZ which exists in the data lead-in area DTLDI, a structure in the recording management zone RMZ (or expanded recording management zone: referred to as expanded RMZ) which exists in the border-in BRDI or bordered area BRDA described later is also identical to the structure shown in FIG. 36 (b) without being limited thereto. In the present embodiment, in the case where a first bordered area BRDA#1 is closed or in the case where the terminating process (finalizing) of the data area DTA is carried out, a processing operation for padding all the reserved area 273 shown in FIG. 36 (b) with the latest recording management data RMD duplication zone is carried out. In this manner, the following advantageous effects are attained: 1) An "unrecorded" reserved area 273 is eliminated, and the stabilization of tracking correction due to a DPD (Differential Phase Detection) technique is guaranteed; 2) the latest recording management data RMD is overwritten in the past reserved area 273, thereby remarkably improving the reliability at the time of reproduction relating to the last recording management data RMD; and 3) an event that different items of recording management data RMD are mistakenly recorded in an unrecorded reserved area 273 can be prevented. The above processing method is not limited to the recording management zone RMZ contained in the data lead-in area DTLDI. In the present embodiment, with respect to the recording management zone RMZ (or expanded recording management zone: referred to as expanded RMZ) which exists in the border-in BRDI or bordered area BRDA described later, in the case where the corresponding bordered area BRDA is closed or in the case where the terminating process (finalizing) of the data area DTA is carried out, a processing operation for padding all the reserved area 273 shown in FIG. 36 (b) with the latest recording management data RMD is carried out. The RMD duplication zone RDZ is divided into the RDZ lead-in area RDZLI and a recording area 271 of the last recording management data RMD duplication zone RDZ of the corresponding RMZ. The RDZ lead-in area RDZLI is composed of a system reserved field SRSF whose data size is 48 KB and a unique ID field UIDF whose data size is 16 KB, as shown in FIG. 36 (b). All "OOh" are set in the system reserved field SRSF. The present embodiment is featured in that DRZ lead-in area RDZLI is recorded in the data lead-in area DTLDI which can be additionally written. In the writeonce type information storage medium according to the present embodiment, the medium is shipped with the RDZ lead-in area RDZLI being in an unrecorded state immediately after manufacturing. In the user's information recording/reproducing apparatus, at a stage of using this write-once type information storage medium, RDZ lead-in area RDZLI information is recorded. Therefore, it is determined whether or not information is recorded in this RDZ lead-in area RDZLI immediately after the write-once type information storage medium has been mounted on the information recording/reproducing apparatus, thereby making it possible to easily know whether or not the target write-once type information storage medium is in a state immediately after manufacturing/shipment or has been used at least once. Further, as shown in FIG. 36, the present embodiment is secondarily featured in that the RMD duplication zone RDZ is provided at the inner periphery side than the recording management zone RMZ which corresponds to a first bordered area BRDA, and the RDZ lead-in RDZLI is arranged in the RMD duplication zone RDZ. The use efficiency of information acquisition is improved by arranging information (RDZ lead-in area RDZLI) representing whether or not the write-once type information storage medium is in a state immediately after manufacturing/shipment or has been used at least once in the RMD duplication zone RDZ used for the purpose of a common use (improvement of reliability of RMD). In addition, the RDZ lead-in area RDZLI is arranged at the inner periphery side than the recording management zone RMZ, thereby making it possible to reduce a time required for acquisition of required information. When the information storage medium is mounted on the information recording/reproducing apparatus, the information recording/reproducing apparatus starts reproduction from the burst cutting area BCA arranged at the innermost periphery side, as described in FIG. 31, and sequentially changes a reproducing location from the system lead-in SYLSI to the data lead-in area DTLDI while the reproduction position is sequentially moved to the innermost periphery side. It is determined whether or not information has been recorded in the RDZ lead-in area RDZLI contained in the RMD duplication zone RDZ. In a write-once type information storage medium in which no recording is carried out immediately after shipment, no recording management data RMD is recorded in the recording management zone RMZ. Thus, in the case where no information is recorded in the RDZ lead-in area RDZLI, it is determined that the medium is "unused immediately after shipment", and the reproduction of the recording management zone RMD can be eliminated, and a time required for acquisition of required information can be reduced. As shown in FIG. 36 (c), a unique ID area UIDF records information relating to an information recording/reproducing apparatus for which the writeonce type information storage medium immediately after shipment has been first used (i.e., for which recording has been first started). That is, this area records a drive manufacturer ID 281 of the information recording/reproducing apparatus or serial number 283 and model number 284 of the information recording/reproducing apparatus. The unique ID area UIDF repeatedly records the same information for 2 KB (strictly, 2048 bytes) shown in FIG. 36 (c). Information contained in the unique disk ID 287 records year information 293, month information 294, date information 295, time information 296, minutes information 297, and seconds information 298 when the storage medium has been first used (recording has been first started). A data type of respective items of information is described in HEX, BIN, ASCII as described in FIG. 36 (d), and two types or four bytes are used. The present embodiment is featured in that the size of an area of this RDZ lead-in area RDZLI and the size of the one recording management data RMD are 64 KB, i.e., the user data size in one ECC block becomes an integer multiple. In the case of the write-once type information storage medium, it is impossible to carry out a processing operation for rewriting ECC block data after changed in the information storage medium after changing part of the data contained in one ECC block. Therefore, in particular, in the case of the write-once type information storage medium, as described later, data is recorded in recording cluster units composed of an integer multiple of a data segment including one ECC block. Therefore, the size of the area of the RDZ lead-in area RDZLI and the size of such one item of recording management data RMD are different from a user data size in an ECC block, there is a need for a padding area or a stuffing area for making adjustment to the recording cluster unit, and a substantial recording efficiency is lowered. As in the present embodiment, the size of the area of the RDZ lead-in area RDZLI and the size of such one item of recording management data RMD are set to an integer multiple of 64 KB, thereby making it possible to lower the recording efficiency. A description will be given with respect to a last recording management data RMD recording area 271 of the corresponding RMZ shown in FIG. 36 (b). As described in Japanese Patent No. 2621459, there is a method for recording intermediate information at the time of interruption of recording inwardly of the lead-in area. In this case, every time recording is interrupted or every time an additional writing process is carried out, it is necessary to serially additionally write intermediate information in this area (recording management data RMD in the present embodiment). Thus, if such recording interruption or additional writing process is frequently repeated, there is a problem that this area becomes full immediately and a further adding process cannot be carried out. In order to solve this problem, the present embodiment is featured in that an RMD duplication zone RDZ is set as an area capable of recording the recording management data RMD updated only when a specific condition is met and the recording management data RMD sampled under such a specific condition is recorded. Thus, there is attained advantageous effect that the RMD duplication zone RDZ can be prevented from being full and the numbers of additional writings enable with respect to the writeonce type information storage medium can be remarkably improved by lowering the frequency of the recording management data RMD additionally written in the RMD duplication zone RDZ. In parallel to this effect, the recording management data updated every time an additional writing process is carried out is serially additionally written in the recording management zone RMZ in the border-in area BRDI shown in FIG. 36 (a) (in the data lead-in area DTLDI as shown in FIG. 36 (a) with respect to the first bordered area BRDA#1) or the recording management zone RMZ utilizing an R zone described later. When a new recording management zone RMZ is created, for example, when the next bordered area BRDA is created (new border-in area BRDI is set) or when a new recording management zone RMZ is set in an R zone, the last recording management data RMD (the newest RMD in a state immediately before creating a new recording management zone RMZ) is recorded in (the corresponding last recording management data RMD recording area 271) contained in the RMD duplication zone RDZ. In this manner, there is attained advantageous effect that a newest RMD position search is facilitated by utilizing this area in addition to a significantly increase of additional writing enable count for the write-once type information storage medium. FIG. 38 shows a data structure in the recording management data RMD shown in FIG. 36. FIG. 38 shows the same contents of FIG. 36. As described previously, in the present embodiment, the border-in area BRDI for the first bordered area BRDA#1 is partially compatible with the data lead-in area DTLDI, and thus, the recording management data RMD#1 to #3 corresponding to the first bordered area are recorded in the recording management zone RMZ in the data lead-in area DTLDI. In the case where no data is recorded in the data area DTA, the inside recording management zone RMZ is provided as a reserved area 273 in which all data is in an unrecorded state. The recording management data RMD updated every time data is additionally written in the data area DTA is recorded in first location contained in this reserved area 273, and the corresponding recording management data RMD is sequentially additionally written in the first bordered area contained in the recording management zone RMZ. The size of the recording management data RMD additionally written each time in the recording management zone RMZ is defined as 64 KB. In the present embodiment, one ECC block is composed of 64 KB data, and thus, an additional writing process is simplified by adjusting the data size of this recording management data RMD to conform with one ECC block size. As described later, in the present embodiment, one data segment 490 is configured by adding part of a guard area before and after one ECC block data 412, and recording clusters 540 and 542 in units of additional writing or rewriting are configured by adding expanded guard fields 258 and 259 to one or more (n) data segments. In the case of recording the recording management data RMD, the recording clusters 540 and 542 including only one data segment (one ECC block) are sequentially additionally written in this recording management zone RMZ. As described later, a length of a location for recording one data segment 531 corresponds to that of one physical segment block composed of seven physical segments 550 to 556. FIG. 38 (c) shows a data structure in one recording management data RMF#1. FIG. 38 (c) shows a data structure in recording management data RMD#1 contained in the data lead-in area DTLDI. The illustrated data structure is identical to a data structure in the recording management data RMD#A and #B (FIG. 36 (b)) recorded in the RMD duplication zone RDZ; (expanded) recording management data RMD recorded in a border-in area BRDI described later; (expanded) recording management data RMD recorded in an R zone; and copy CRMD of RMD recorded in the border-out area BRDO (FIG. 39 (d)) as well. As shown in FIG. 38 (c) , one item of recording management data RMD is composed of a reserved area and RMD fields ranging from "0" to "21". In the present embodiment, 32 physical sectors are included in one ECC block composed of 64 KB user data, and user data of 2 KB (strictly, 2048 bytes) is recorded in one physical sector. Each RMD field are assigned by 2048 bytes in conformance to a user data size recorded in this physical sector, and relative physical sector numbers are set. RMD fields are recorded on a write-once type information storage medium in order of these relative physical sector numbers. The contents of data recorded in each RMD field are as follows: RMD field 0 ... Information relating to disk state and data area allocation (information relating to location for allocating a variety of data in data area) RMD field 1 ... Information relating to used test zone and information relating to recommended recording waveform RMD field 2 ... User available area RMD field 3 ... Start position information on border area and information relating to expanded RMZ position RMD fields 4 to 21 ... Information relating to position of R zone As shown in FIG. 35 in any of the read-only type, write-once type, and rewritable-type information storage medium, the present embodiment is featured in that a system lead-in area is arranged at an opposite side of a data area while a data lead-in area is sandwiched between the two areas, and further, as shown in FIG. 31, the burst cutting area BCA and the data lead-in area DTLDI are arranged at an opposite side to each other while the system lead-in area SYSDI is sandwiched between the two areas. When an information storage medium is inserted into the information reproducing apparatus or information recording/reproducing apparatus shown in FIG. 11, the information reproducing apparatus or information recording/reproducing apparatus carries out processing in accordance with the steps of: 1) reproducing information contained in the burst cutting area BCA; 2) reproducing information contained in the information data zone CDZ contained in the system leadin area SYLDI; 3) reproducing information contained in the data lead-in area DTLDI (in the case of a write-once type or a rewritable-type medium); 4) readjusting (optimizing) a reproduction circuit constant in the reference code zone RCZ; and 5) reproducing information recorded in the data area DTA or recording new information. As shown in FIG. 35, information is sequentially arranged from the inner periphery side along the above processing steps, and thus, a process for providing an access to an unnecessary inner periphery is eliminated, the number of accesses is reduced, and the data area DTA can be accessed. Thus, there is attained advantageous effect that a start time for reproducing the information recording in the data area or recording new information is accelerated. In addition, RPML is used for signal reproduction in the data lead-in area DTDLI and data area DTA by utilizing a slice level detecting system for signal reproduction in the system lead-in area SYLDI. Thus, if the data lead-in area DTLDI and the data area DTA are made adjacent to each other, in the case where reproduction is carried out sequentially from the inner periphery side, a signal can be stably reproduced continuously merely by switching a slice level detecting circuit to a PRML detector circuit only once between the system lead-in area SYLDI and the data lead-in area DTLDI. Thus, the number of reproduction circuit switchings along the reproduction procedures is small, thus simplifying processing control and accelerating a data intra-area reproduction start time. FIG. 37 shows a comparison of the data structures in the data areas DTA and the data lead-out areas DTLDO in a variety of information storage mediums. FIG. 37 (a) shows a data structure of a read-only type information storage medium; FIGS. 37(b) and 37(c) each show a data structure of a writing-type information storage medium; and FIG. 37(d) to 37(f) each show a data structure of a write-once type information storage medium. In particular, FIGS. 37 (b) and 37(d) each show a data structure at the time of an initial state (before recording); and FIGS. 37(c), 37 (e) and 37 (f) each show a data structure in a state in which recording (additional writing or rewriting) has advanced to a certain extent. As shown in FIG. 37 (a), in the read-only type information storage medium, the data recorded in the data lead-out area DTLDO and the system lead-out area SYLDO each have a data frame structure (described later in detail) in the same manner as in the buffer zone 1 BFZ1 and buffer zone 2 BFZ2 shown in FIGS. 35 (a) to 35 (c), and all values of the main data contained therein are set to "OOh". In the read-only type information storage medium, a user data prerecording area 201 can be fully used in the data area DTA. However, as described later, in any of the embodiments of the write-once information storage medium and rewritable-type information storage medium as well, user rewriting/additional writing enable ranges 202 to 205 are narrower than the data area DTA. In the write-once information storage medium or rewritable-type information storage medium, an SPA (Spare Area) is provided at the innermost periphery of the data area DTA. In the case where a defect has occurred in the data area DTA, a substituting process is carried out by using the spare area SPA. In the case of the rewritable-type information storage medium, the substitution history information (defect management information) is recorded in a defect management area 1 (DMAl) and a defect management area 2 (DMA2) shown in FIG. 35(b); and a detect management area 3 (DMA3) and a defect management area 4 (DMA4) shown in FIGS. 37(b) and 37 (c) . The defect management information recorded in the defect management area 3 (DMAS) and defect management area 4 (DMA4) shown in FIGS. 37(b) and 37(c) are recorded as the same contents of the defect management information recorded in the defect management information 1 (DMAl) and defect management information 2 (DMA2) shown in FIG. 35B. In the case of the write-once type information storage medium, substitution history information (defect management information) in the case where the substituting process has been carried out is recorded in the data lead-in area DTLDI shown in FIG. 35C and copy information C_RMZ on the contents of receding in a recording management zone which exists in a border zone. Although defect management has not been carried out in a current DVD-R disk, DVD-R disks partially having a defect location are commercially available as the manufacture number of DVD-R disks increases, and there is a growing need for improving the reliability of information recorded in a write-once type information storage medium. In the embodiment shown in FIGS. 37A to 37F, a spare area SPA is set with respect to the write-once information storage medium, enabling defect management by a substituting process. In this manner, a defect management process is carried out with respect to the write-once type information storage medium partially having a defect location, thereby making it possible to improve the reliability of information. In the rewritable-type information storage medium or writeonce type information storage medium, in the case where a defect frequently has occurred, a user judges an information recording/reproducing apparatus, and an ESPA, ESPA1, and ESPA2 (Expanded Spare Areas) are automatically set with respect to a state immediately after selling to the user shown in FIGS. 37A and 37D so as to widen a substitute location. In this manner, the expanded spare areas ESPA, ESPA1, and ESPA2 can be set, thereby making it possible to sell mediums with which a plenty of defects occur for a manufacturing reason. As a result, the manufacture yield of mediums is improved, making it possible to reduce a medial price. As shown in FIGS. 37A, 37E and 37F, when the expanded spare areas ESPA, ESPA1, and ESPA2 are expanded in the data area DTA, user data rewriting or additional writing enable ranges 203 and 205 decrease(s), thus making it necessary to management its associated positional information. In the rewritable-type information storage medium, the information is recorded in the defect management area 1 (DMA1) to the defect management area 4 (DMA4) and in the control data zone CDZ, as described later. In the case of the write-once type information storage medium, as described later, the information is recorded in recording management zones RMZ which exist in the data lead-in area DTLDI and in the border-out BRDO. As described later, the information is recorded in the RMD (Recording Management Data) contained in the recording management zone RMZ. The recording management data RMD is updated or additionally written in the receding management zone RMZ every time the contents of management data are updated. Thus, even if an expanded spare area is reset many times, timely updating and management can be carried out. (The embodiment shown in FIG. 37E indicates a state in which an expanded spare area 2 (ESPA2) has been set because further area substituting setting is required due to a number of defects even after the expanded spare area 1 (ESPA1) has been fully used). A guard track zone 3 (GTZ3) shown in FIGS. 37B and 37C each is arranged to separate a defect management area 4 (DMA4) and a drive test zone (DRTS) from each other, and a guard track zone 4 (GTZ4) is arranged to separate a disk test zone DKTZ and a servo calibration zone SCZ from each other. The guard track zone 3 (GTZ3) and guard track zone 4 (GTZ4) are specified as area which inhibits recording by forming a recording mark, as in the guard track zone 1 (GTZl) and guard track zone 2 (GTZ2) shown in FIGS. 35A to 35C. The guard track zone 3 (GTZ3) and the guard track zone 4 (GTZ4) exist in the data lead-out area DTLDO. Thus, in these areas, in the write-once type information storage medium, a pre-groove area is formed in advance, or alternatively, in the rewritable-type information storage medium, a groove area and a land area are formed in advance. As shown in FIGS. 32 to 34, wobble addresses are recorded in advance in the pre-groove area or the groove area and land area, thus judging a current position in the information storage medium by using this wobble addresses. As in FIGS. 35A to 35C, a drive test zone DRTZ is arranged as an area for test writing before an information recording/reproducing apparatus records information in an information storage medium. The information recording/reproducing apparatus carries out test writing in advance in this area, and identifies an optimal recording condition (write strategy). Then, this apparatus can record information in the data area DTA under the optimal recording condition. As shown in FIGS. 35A to 35C, the disk test zone DKTZ is an area provided for manufacturers of information storage mediums to carry out quality test (evaluation). In all of the areas contained in the data lead-out area DTLDO other than the SCZ (Servo Calibration Zone), a pre-groove area is formed in advance in the writeonce type information storage medium, or alternatively, a groove area and a land area are formed in advance in the rewritable-type information storage medium, enabling recording (additional writing or rewriting) of a recording mark. As shown in FIGS. 37C and 37E, the SCZ (Servo Calibration Zone) serves as an emboss pit area 211 in the same manner as in the system lead-in area SYLDI instead of the pre-groove area 214 or the land area and groove area 213. This area forms continuous tracks with emboss pits, which follows another area of the data lead-out area DTLDO. These tracks continuously communicate with each other in a spiral manner, and form emboss pits over 360 degrees along the circumference of the information storage medium. This area is provided to detect a tilt amount of the information storage medium by using a DPD (Deferential Phase Detect) technique. If the information storage medium tilts, an offset occurs with a track shift detection signal amplitude using the DPD technique, making it possible to precisely the tilt amount from the offset amount and a tilting direction in an offset direction. By utilizing this principle, emboss pits capable of DPD detection are formed in advance at the outermost periphery (at the outer periphery in the data lead-out area DTLDO), thereby making it possible to carry out detection with inexpensiveness and high precision without adding special parts (for tilt detection) to an optical head which exists in the information recording/reproducing unit 141 shown in FIG. 11. Further, by detecting the tilt amount of the outer periphery, servo stabilization (due to tilt amount correction) can be achieved even in the data area. In the present embodiment, the track pitches in this servo calibration zone SCZ are adjusted to conform with another area contained in the data lead-out area DTLD, and the manufacturing performance of the information storage medium is improved, making it possible to reduce a media price due to the improvement of yields. That is, although a pre-groove is formed in another area contained in the data leadout area DTLDO in the write-once type information storage medium, a pre-groove is created while a feed motor speed of an exposure section of an original master recording device is made constant at the time of original master manufacturing of the write-once type information storage medium. At this time, the track pitches in the servo calibration zone SCZ are adjusted to conform with another area contained in the data lead-out area DTLDO, thereby making it possible to continuously maintain a motor speed constantly in the servo calibration zone SCZ as well. Thus, the pitch non-uniformity hardly occurs, and the manufacturing performance of the information storage medium is improved. Another embodiment includes a method for adjusting at least either of the track pitches and data bit length in the servo calibration zone SCZ to conform with the track pitches or data bit length of the system lead-in area SYLDI. As described previously, the tilt amount in the servo calibration zone SCZ and its tilt direction are measured by using the DPD technique, and the measurement result is utilized in the data area DTA as well, thereby promoting servo stabilization in the data area DTA. A method for predicting a tilt amount in the data area DTA is featured in that the tilt amount in the system lead-in area SYLDI and its direction are measured in advance by using the DPD technique similarly, and a relationship with the measurement result in the servo calibration zone SCZ is utilized, thereby making it possible to predict the tilt amount. In the case of using the DPD technique, the present embodiment is featured in that the offset amount of the detection signal amplitude relevant to a tilt of the information storage medium and a direction in which an offset occurs, change depending on the track pitches and data bit length of emboss pits. Therefore, there is attained advantageous effect that at least either of the track pitches and data bit length in the servo calibration zone SCZ is adjusted to conform with the track pitches or data bit length of the system lead-in area SYLDI, whereby the detection characteristics relating to the offset amount of the detection signal amplitude and the direction in which an offset occurs are made coincident with each other depending on the servo calibration zone SCZ and the system lead-in area SYLDI; a correlation between these characteristics is easily obtained, and the tilt amount and direction in the data area DTA is easily predicted. As shown in FIGS. 35C and 37D, in the write-once type information storage medium, two drive test zones DRTZ are provided at the inner periphery side and the outer periphery side of the medium. As more test writing operations are carried out for the drive text zones DRTZ, parameters are finely assigned, thereby making it possible to search an optimal recording condition in detail and to improve the precision of recording in the data area DTA. The rewritable-type information storage medium enables reuse in the drive test zone DRTZ due to overwriting. However, if an attempt is made to enhance the recording precision by increasing the number of test writings in the writeonce type information storage medium, there occurs a problem that the drive test zone is used up immediately. In order to solve this problem, the present embodiment is featured in that an EDRTZ (Expanded Drive Test Zone) can be set from the outer periphery to the inner periphery direction, making it possible to expand a drive test zone. In the present embodiment, features relating to a method for setting an expanded drive test zone and a method for carrying out test writing in the set expanded drive test zone are described below. 1) The setting (framing) of expanded drive test zones EDRTZ are sequentially provided collectively from the outer periphery direction (close to the data leadout area DTLDO) to the inner periphery side. - As shown in FIG. 37E, the expanded drive test zone 1 (EDRTZ1) is set as an area collected from a location which is the closest to the outer periphery in the data area (which is the closest to the data leadout area DTLDO); and the expanded drive test zone 1 (EDRTZ1) is used up, thereby making it possible to secondarily set the expanded drive test zone 2 (EDRTZ2) as a corrected area which exists in the inner periphery side than the current position. 2) Test writing is sequentially carried out from the inner periphery side in the expanded dive test zone DDRTZ. - In the case where test writing is carried out in the expanded drive test zone EDRTZ, such test writing is carried out along a groove area 214 arranged in a spiral shape from the inner periphery side to the outer periphery side, and current test writing is carried out for an unrecorded location that immediately follows the previously test-written (recorded) location. The data area is structured to be additionally written along the groove area 214 arranged in a spiral manner from the inner periphery side to the outer periphery side. A processing operation from "checking immediately test-written location" to "carrying out current test writing" can be serially carried out by using a method for sequentially carrying out additional writing a location that follows a test writing location in which test writing in the expanded drive test zone has been carried out immediately before, thus facilitating a test writing process and simplifying management of the test-written location in the expanded drive test zone EDRTZ. 3) The data lead-out area DTLDO can be reset in the form including the expanded drive test zone. FIG. 37E shows an example of setting two areas, i.e., an expanded spare area 1 (ESPAl) and an expanded spare area 2 (ESPA2) in the data area DTA and setting two areas, i.e., the expanded drive test zone 1 (EDRTZ1) and expanded drive test zone 2 (EDRTZ2). In this case, as shown in FIG. 37F, the present embodiment is featured in that the data lead-out area DTLO can be reset with respect to an area including up to the expanded drive test zone 2 (EDRTZ2). Concurrently, the range of data area DTA is reset in a range-narrowed manner, making it easy to manage an additional writing enable range 205 of the user data which exists in the data area DTA. In the case where the resetting has been provided as shown in FIG. 37F, a setting location of the expanded spare area 1 (ESPAl) shown in FIG. 37E is regarded as an "expanded spare area which has already been used up", and an unrecorded area (area enabling additional test writing) is managed only in the expanded spare area 2 (ESPA2) contained in the expanded drive test zone EDRTZ if any. In this case, non-defect information which is recorded in the expanded spare area 1 (ESPAl) and which has been used up for substitution is transferred to a location of an area which is not substituted in the expanded spare area 2 (ESPTA2), and defect management information is rewritten. The start position information on the reset data lead-out area DTLDO is recorded in allocation position information on the latest (updated) data area DTA of RMD field 0 contained in the recording management data RMD, as shown in FIG. 44. A structure of a border area in a write-once type information storage medium will be described here with reference to FIG. 40. When one border area has been first set in the write-once information storage medium, an bordered area (Bordered Area) BRDA#1 is set at the inner periphery size (which is the closest to the data lead-in area DTLDI), as shown in FIG. 40 (a), and then, a border out (Border out) BRDO that follows the above area is formed. Further, in the case where an attempt is made to set a next bordered area (Bordered Area) BRDA2, as shown in FIG. 40 (b), a next (1) border in area BRDI that follows the preceding 1 border out area BRDO is formed, and then, a next bordered area BRDA2 is set. In the case where an attempt is made to close the next bordered area BRDA2, a (2) border out area BRDO that immediately follows the area BRDA2 is formed. In the present embodiment, a state in which the next ((1) border in area BRDI) that follows the preceding (1) border out area BRDO is formed and combined is referred to as a border zone BRDZ. The border zone BRDZ is set to prevent an optical head from overrun between the bordered areas BRDAs when reproduction has been carried out by using the information reproducing apparatus (on the presumption that the DPD detecting technique is used). Therefore, in the case where a write-once type information storage medium having information recorded therein is reproduced by using a read-only apparatus, it is presumed that a border close process is made such that the border out area BRDO and border-in area BRDI are already recorded and the border out area BRDO that follows the last bordered area BRDA is recorded. The first bordered area BRDA#1 is composed of 4080 or more physical segment blocks, and there is a need for the first bordered area BRDA#1 to have a width of 1.0 mm or more in a radial direction on the write-once type information storage medium. FIG. 40 (b) shows an example of setting an expanded drive test zone EDRTZ in the data area DTA. FIG. 40 (c) shows a state obtained after finalizing a write-once information storage medium. FIG. 40 (c) shows an example in which an expanded drive test zone EDRTZ is incorporated in the data lead-out area DTLDO, and further, an expanded spare area ESPA has been set. In this case, a user data adding enable range 205 is fully padded with the last border out area BRDO. FIG. 40 (d) shows a detailed data structure in the border zone area BRDZ described above. Each item of information is recorded in size units of one physical segment blocks (physical segment block). Copy information C_RMZ on the contents recorded in a recording management zone is recorded at the beginning of the border out area BRDO, and a border end mark (Stop Block) STB indicating the border out area BRDOP is recorded. Further, in the case the next border in area BDI is reached, a first mark (Next Border Marker) NBM indicating that a next border area reaches an "Nl-th" physical segment block counted from a physical segment block in which the border end mark (Stop Block) STC has been recorded; a second mark NBM indicating that a next border region reaches an "N2-th" physical segment block; and a third mark NBM indicating that a next border region reaches an "N3-th" mark NBM are discretely recorded in a total of three locations on a size by size basis of one physical segment block, respectively. Updated physical format information U_PFI is recorded in the next border-in area BRDI. In a current DVD-R or a DVD-RW disk, in the case where a next border is not reached (in the last border out area BRDO), a location in which "a mark NBM indicating a next border" should be recorded (a location of one physical segment block size) shown in FIG. 40 (d) is maintained as a "location in which no data is recorded". If border closing is carried out in this state, this write-once type information storage medium (current DVD-R or DVD-RW disk) enters a state in which reproduction can be carried out by using a conventional DVD-ROM drive or a conventional DVD player. The conventional DVD-ROM drive or the conventional DVD player utilizes a recording mark recorded on this write-once type information storage medium (current DVD-R or DVD-RW disk) to carry out track shift detection using the DPD (Differential Phase Detect) technique. However, in the above described "location in which no data is recorded", a recording mark does not exist over one physical segment block size, thus making it impossible to carry out track shift detection using the DPD (Differential Phase Detect) technique. Thus, there is a problem that a track servo cannot be stably applied. In order to solve the above described problem with the current DVD-R or DVD-RW disk, the present embodiment newly employed methods for: 1) in the case where a next border area is reached, recording data on a specific pattern in advance in a "location in which the mark NBM indicating a next border should be recorded"; and 2) carrying out an "overwriting process" in a specific recording pattern partially and discretely with respect to a location indicating "the mark NBM indicating a next border" in which, in the case where a next border area is reached, the data on the specific pattern is recorded in advance, thereby utilizing identification information indicating that "a next border area is reached". By setting a mark indicating a next border due to overwriting, there is attained advantageous effect that, even in the case where a next border area is reached as shown in item (1), a recording mark of a specific pattern can be formed in advance in a "location in which the mark NBM indicating a next border should be recorded", and, after border closing, even if a read-only type information reproducing apparatus carries out track shift detection in accordance with the DPD technique, a track servo can be stably applied. If a new recording mark is overwritten partially on a portion at which a recording mark has already been formed in a write-once type information storage medium, there is a danger that the stability of a PLL circuit shown in FIG. 11 is degraded in an information recording/reproducing apparatus or an information reproducing apparatus. In order to overcome this danger, the present embodiment further newly employs methods for: 3) when overwriting is carried out at a position of "the mark NBM indicating a next border" of one physical segment block size, changing an overwrite state depending on a location contained in the same data segment; 4) partially carrying out overwriting in a sync data 432 and disabling overwriting on a sync code 431; and 5) carrying out overwriting in a location excluding data ID and IED. As described later in detail, data fields 411 to 418 for recording user data and guard areas 441 to 448 are alternately recorded on an information storage medium. A group obtained by combining the data fields 411 to 418 and the guard areas 441 to 448 is called a data segment 490, and one data segment length coincides with one physical segment block length. The PLL circuit 174 shown in FIG. 11 facilitates PLL lead-in in VFO areas 471 and 472 in particular. Therefore, even if PLL goes out immediately before the VFO areas 471 and 472, PLL re-lead-in is easily carried out by using the VFO areas 471 and 472, thus reducing an effect on a whole system in the information recording/reproducing apparatus or information reproducing apparatus. There is attained advantageous effect that (3) an overwrite state is changed depending on a location in a data segment internal location, as described above, by utilizing this state, and an overwrite amount of a specific pattern is increased at a back portion close to the VFO areas 471 and 472 contained in the same data segment, thereby making it possible to facilitate judgment of "a mark indicating a next border" and to prevent degradation of the precision of a signal PLL at the time of reproduction. As described in detail with respect to FIGS. 83 (a) to 83 (f) and FIGS. 62 (a) and 62 (b), one physical sector is composed of a combination of a location in which sync codes (SYO to SY3) are arranged and the sync data 434 arranged between these sync codes 433. The information recording/reproducing apparatus or the information recording apparatus samples sync codes 43 (SYO to SY3) from a channel bit pattern recorded on the information storage medium, and detects a boundary of the channel bit pattern. As described later, position information (physical sector numbers or logical sector numbers) on the data recorded on the information storage medium is sampled from data ID information. A data ID error is sensed by using an IED arranged immediately after the sampled information. Therefore, the present embodiment enables (5) disabling overwriting on data ID and IED and (4) partially carrying out overwriting in the sync data 432 excluding the sync code 431, thereby enabling detection of a data ID position and reproduction (content-reading) of the information recorded in data ID by using the sync code 431 in the "mark NMB indicating a next border". FIG. 39 shows another embodiment which is different from that shown in FIG. 40 relating to a structure of a border area in a write-once type information storage medium. FIGS. 39 (a) and 39 (b) show the same contents of FIGS. 40 (a) and 40 (b). FIG. 39 (a) to 39 (d) are different from FIG. 40 (c) in terms of a state that follows finalization of a writeonce type information storage medium. For example, as shown in FIG. 39 (c), after information contained in the bordered area BRDA#3 has been recorded, in the case where an attempt is made to achieve finalization, a border out area BRDO is formed immediately after the bordered area BDA#3 as a border closing process. Then, a terminator area TRM is formed after the border out area DRDO which immediately follows the bordered area BRDA#3, thereby reducing a time required for finalization. In the embodiment shown in FIG. 40, there is a need for padding a region that immediately precedes the expanded spare area ESPA with border out area BRDO. There occurs a problem that a large amount of time is required to form this border out area BRDO, thereby expanding the finalization time. In contrast, in the embodiment shown in FIG. 39 (c), a comparatively short terminator area TRM is set in length; all of the outer areas than the terminator TRM are redefined as a data lead-out area NDTLDO; and an unrecorded portion which is outer than the terminator TRM is set as a user disable area 911. That is, when the data area DTA is finalized, the terminator area TRM is formed at the end of recording data (immediately after the border out area BRDO). All the information on the main data contained in this area is set to "OOh". Type information on this area is set in an attribute of the data lead-out area NDTLDO, whereby this terminator area TRM is redefined as a new data lead-out area NDTLDO, as shown in FIG. 39 (c). Type information on this area is recorded in area type information 935 contained in data ID, as described later. That is, the area type information 935 contained in the data ID in this terminator area TRM is set to "lOb", as shown in FIGS. 50 (a) to 50 (d), thereby indicating that data exists in the data lead-out area DTLDO. The present embodiment is featured in that identification information on a data lead-out position is set by the data ID internal area type information 935. In an information recording/reproducing apparatus or an information reproducing apparatus shown in FIG. 11, let us consider a case in which an information recording/reproducing unit 141 has provided a random access to a specific target position on a write-once type information storage medium. Immediately after random access, the information recording/reproducing unit 141 must reproduce a data ID and decode a data frame number 922 in order to know where on the writeonce type information storage medium has been reached. In the data ID, area type information 935 exists near the data frame number 922. At the same time, it is possible to immediately identify whether or not the information recording/recording unit 141 exists in the data lead-out area DTLDO merely by decoding this area type information 935. Thus, a simplification and high speed access control can be made. As described above, identification information on the data lead-out area DTLDO is provided by data ID internal setting of the terminator area TRM, thereby making it easy to detect the terminator area TRM. As a specific example, in the case where the border out area BRDO is set as an attribute of the data lead-out area NDTLDO (that is, in the case where the area type information 935 contained in the data ID of a data frame in the border out BRDO is set to "lOb"), the setting of this terminator area TRM is not provided. Therefore, when the terminator area TRM is recorded, the area having an attribute of the data lead-out area NDTLDO, this terminator area TRM is regarded as part of the data lead-out area NDTLDO, thus disabling recording into the data area DTA. As a result, as in FIG. 39 (c), a user disable area 911 may remain. In the present embodiment, the size of the terminator area TRM is changed depending on a location on a write-once type information storage medium, thereby reducing a finalization time and achieving efficient processing. This terminator area TRM indicates an end position of recording data. In addition, even in the case where this area is used in a read-only apparatus, which carries out track shift detection in accordance with a DPD technique, the terminator area, is utilized to prevent overrun due to a track shift. Therefore, a width in a radial direction on the write-once type information storage medium having this terminator area TRM (width of a portion padded with the terminator area TRM) must be a minimum of 0.05 nm or more because of the detection characteristics of the read-only apparatus. A length of one cycle on the write-once type information storage medium is different depending on a radial position, and thus, the number of physical segment blocks included in one cycle is also different depending on the radial position. Thus, the size of the terminator area TRM is different depending on the physical sector number of a physical sector which is positioned at the beginning of the terminator area TRM, and the size of the terminator area TRM increases as the physical sector go to the outer periphery side. A minimum value of a physical sector number of an allowable terminator area TRM must be greater than "04FEOOh". This derived from a restrictive condition in which the first bordered area DRDA#1 is composed of 4080 or more physical segment blocks, making it necessary for the first bordered area BRDA#1 to have a width equal to or greater than 1.0 mm in a radial direction on the write-once type information storage medium. The terminator area TRM must start from a boundary position of physical segment blocks. In FIG. 39 (d), a location in which each item of information is to be recorded is set for each physical segment block size for the reason described previously, and a total of 64 KB user data recorded to be distributed in 32 physical sectors is recorded in each physical segment block. A relative physical segment block number is set with respect to a respective one item of information, as shown in FIG. 39 (d) , and the items of information are sequentially recorded in the write-once type information storage medium in ascending order from the lowest relative physical segment number. In the embodiment shown in FIGS. 39 (a) to 39 (d), copies CRMD#0 to CRMD#4 of RMD, which are the same contents, are overwritten five times in a copy information recording zone C_TRZ of the contents recorded in the recording management zone shown in FIG. 40 (d). The reliability at the time of reproduction is improved by carrying out such overwriting, and, even if dust or scratch adheres onto a write-once information storage medium, the copy information CRMD on the contents recorded in the recording management zone can be stably reproduced. Although the border end mark STB shown in FIG. 39 (d) coincides with a border end mark STB shown in FIG. 40 (d), the embodiment shown in FIG. 39 (d) does not have the mark NBM indicating a next border, unlike the embodiment shown in FIG. 40 (d). All the information on the main data contained in reserved areas 901 and 902 is set to"00h". At the beginning of the border-in area BRDI, information which is completely identical to updated physical format information U_PFI is multiply written six times from N+l to N+6, configuring the updated physical format information U_PFI shown in FIG. 40. The thus updated physical format information U_PFI is multiply written, thereby improving the reliability of information. In FIG. 39 (d), the present embodiment is featured in that the recording management zone RMZ in the border zone is provided in the border-in area BRDI. As shown in FIG. 36 (a), the size of the recording management zone RMZ contained in the data lead-in area DTLDI is comparatively small. If the setting of a new bordered area BRDA is frequently repeated, the recording management data RMD recorded in the recording management zone RMZ is saturated, making it impossible to set a new bordered area BRDA midway. As in the embodiment shown in FIG. 39 (d), there is attained advantageous effect that a recording management zone for recording the recording management data RMD relating to the bordered area BRDA#3 that follows is provided in the border-in area DRDI, whereby the setting of a new bordered area BRDA can be provided a number of times and the additional writing count in the bordered area BRDA can be significantly increased. In the case where the bordered area BRDA#3 that follows the border-in area BRDI including the recording management zone RMZ in this border zone is closed or in the case where the data area DTA is finalized, it is necessary to repeatedly record all the last recording management data RMD into a spare area 273 (FIG. 38 (b)) established in an unrecorded state in the recording management zone RMZ, and pad all the spare area with the data. In thins manner, the spare area 273 in an unrecorded state can be eliminated, a track shift (due to DPD) at the time of reproduction in a read-only apparatus can be prevented, and the reproduction reliability of the recording management data RMD can be improved by multiple recording of the recording management data. All the data contained in a reserve area 903 are set to "OOh". Although the border out area BRDO serves to prevent overrun due to a track shift in the read-only apparatus while the use of DPD is presumed, there is no need for the border-in area BRDI to have a particularly large size other than having the updated physical format information U_PFI and the information contained in recording management zone RMZ in the border zone. Therefore, an attempt is made to reduce the size to the minimum in order to reduce a time (required for border zone BRDZ recording) at the time of setting a new bordered area BRDA. With respect to FIG. 39 (a), before forming the border out area BRDO due to border closing, there is a high possibility that the user data additional writing enable range 205 is sufficiently large, and a large number of additional writing is carried out. Thus, it is necessary to largely take a value of "M" shown in FIG. 39 (d) so that recording management data can be recorded a number of times in the recording management zone RMZ in a border zone. In contrast, with respect to FIG. 39 (b), in a state that precedes border closing of the bordered area BRDA#2 and that precedes recording the border out area BRDO, the user data additional writing enable range 205 narrows, and thus, it is considered that not the number of additional writings of the recording management data to be additionally written in the recording management zone RMZ in the border zone does not increase so much. Therefore, the setting size "M" of the recording management zone RMZ in the border-in area BRDI that immediately precedes the bordered area BRDA#2 can be taken to be relatively small. That is, as a location in which the border-in area BRDI is arranged goes to the inner periphery side, the number of predicted additional writings of the recording management data increases. As the location goes to the outer periphery, the number of predicted additional writings of the recording management data decreases. Thus, the present embodiment is featured in that the size of the border-in area BRDI is reduced. As a result, the reduction of a time for setting a new bordered area BRDA and processing efficiency can be achieved. A logical recording unit of the information recorded in the bordered area BRDA shown in FIG. 40 (c) is referred to as an R zone. Therefore, one bordered area BRDA is composed of at least one or more R zones. In a current DVD-ROM, as a file system, there are employed a file system called a "UDF bridge" in which both of file management information which conforms with a UDF (Universal Disc Format) and file management information which conforms with ISO 9660 are recorded in one information storage medium at the same time. In a file management method which conforms with ISO 9660, there is a rule that one file must be continuously recorded in an information storage medium. That is, information contained in one file is disabled to be divisionally arranged at a discrete position on an information storage medium. Therefore, for example, in the case where information has been recorded in conformance with the above UDF bridge, all the information configuring one file is continuously recorded. Thus, it is possible to adapt this area in which one file is continuously recorded so as to configure one R zone. FIG. 41 shows a data structure in the control data zone CDZ and the R-physical information zone RIZ. As shown in FIG. 41 (b), physical format information (PFI) and disc manufacturing information (DMI) exist in the control data zone CDZ, and similarly, an DMI (Disc Manufacturing Information) and R PFI (R-Physical Format Information) are contained in an R-physical information zone RIZ. Information 251 relating to a medium manufacture country and medium manufacturer's nationality information 252 are recorded in medium manufacture related information DMI. When a commercially available information storage medium infringes a patent, there is a case in which an infringement warning is supplied to such a country in which a manufacturing location exists or an information storage medium is consumed (or used). A manufacturing location (country name) is identified by being obliged to record the information contained in an information storage medium, and a patent infringement warning is easily supplied, whereby an intellectual property is guaranteed, and technical advancement is accelerated. Further, other medium manufacture related information 253 is also recorded in the medium manufacture related information DMI. The present embodiment is featured in that type of information to be recorded is specified depending on a recording location (relative byte position from the beginning) in physical format information PFI or Rphysical format information R_PFI. That is, as a recording location in the physical format information PFI or R-physical format information R_PFI, common information 261 in a DVD family is recorded in an 32- byte area from byte 0 to byte 31; common information 262 in an HD_DVD family which is the subject of the present embodiment is recorded in 96 bytes from byte 32 to byte 127; unique information (specific information) 263 relating to various specification types or part versions are recording in 384 bytes from byte 128 to byte 511; and information corresponding to each revision is recorded in 1536 bytes from byte 512 to byte 2047. In this way, the information allocation positions in the physical format information are used in common depending on the contents of information, whereby the locations of the recorded information are used in common depending on medium type, thus making it possible to carry out in common and simplify a reproducing process of an information reproducing apparatus or an information recording/reproducing apparatus. The common information 261 in a DVD family recorded in byte 0 to byte 31, as shown in FIG. 41D, is divided into: information 267 recorded in common in all of a read-only type information storage medium and a rewritable-type information storage medium, and a write-once type information storage medium recorded from byte 0 to byte 16; and information 268 which is recorded in common in the rewritable-type information storage medium and the write-once type information storage medium from byte 17 to byte 31 and which is not recorded in the read-only type medium. FIG. 55 shows another embodiment relating to a data structure in the control data zone shown in FIG. 41. As shown in FIG. 35C, the control data zone CDZ is configured as part of an emboss bit area 211. This control data zone CDZ is composed of 192 data segments start from physical sector number 151296 (024FOOh). In the embodiment shown in FIG. 55, a control data section CTDS composed of 16 data segments and a copyright data section CPDS composed of 16 data segments are arranged on two by two basis in the control data zone CDZ, and a reserve area RSV is set between these two sections. By allocating these sections on a two by two basis, a physical distance between the two sections is widened, and an effect relevant to a burst error which occurs due to a scratch of an information storage medium surface or the like is reduced. In one control data section CTDS, as shown in FIG. 55 (c), physical sector information on first three relative sector numbers "0" to "2" is recorded to be repeated 16 times. Multiple writing is carried out 16 times, thereby improving the reliability of recording information. Physical format information PFI described in FIG. 42 or 54 is recorded in a first physical sector in a data segment whose relative physical sector number is "0". Disk manufacture related information DMI is recorded in a second physical sector in a data segment whose relative physical sector number is "1". Furthermore, copyright protection information CPI is recorded in the third physical sector in the data segment in which relative number of the physical sector is "2". A reserved area RSV whose relative physical sector number is "3" to "31" is reserved so as to be available in a system. As the contents of the above described disk manufacture related information DMI, a disk manufacturer's name (Disc Manufacturer's name) is recorded in 128 bytes from byte 0 to byte 127; and information on a location in which a manufacturer exists (information indicating where this disk has been manufactured" is recorded in 128 bytes from byte 128 to byte 255. The above disk manufacturer's name is described in ASCII codes. However, the ASCII codes available in use as a disk manufacturer's name are limited to a starting byte to "ODh" and "20h" to "7Eh". A disk manufacture's name is described from the first byte 1 in this area, and the remaining portions in this area are padded (terminated) with data "ODh". With respect to information on a location in which the above disk manufacturer exists, the information indicating where this disk has been manufactured, a country or a region is described in the ASCII codes. This area is limited to a starting byte to "ODh" and "20h" to "7Eh" which are available ASCII codes as in the disk manufacturer's name. The information on a location in which a disk manufacturer exists is described from the first byte I in this area, and the remaining portions in this area are padded (terminated) with data "ODh". Alternatively, another describing method includes setting an allowable size in the range of the first byte to "ODh" as the information on a location in which a disk manufacturer exists. In the case where the information on a location in which a disk manufacturer exists is long, the information is terminated at "ODh", and a region subsequent to "ODh" may be padded with data "20h". The reserved area RSV shown in FIG. 55 (c) is fully padded with data "OOh". FIG. 42 shows a comparison depending on a medium type (read-only type, rewritable-type, or write-once type) of information contained in the physical format information PFI with the contents of specific information contained in the physical format information PFI or R-physical format information R_PFI shown in FIG. 41 or FIG. 55. As information 267 recorded in common to all of the read-only type, rewritable-type, and write-once type medium in the common information 261 in the DVD family, there are sequentially recorded from byte positions 0 to 16: specification type (read-only, rewriting, or writeonce) information and version number information; medium size (diameter) and maximum allowable data transfer rate information; a medium structure (single layer or double layer or whether or not emboss pit, additional writing area, or rewriting area exists); a recording density (line density and track density) information; allocation location information on data region DTA; and information on whether or not burst cutting area BCA exists (both of them exist in the present embodiment). As information 268 in common information 261 of a DVD family and recorded in common to a rewriting type and a write-once type, there are recorded: revision number information for sequentially defining a maximum recording speed from byte 28 to byte 31; revision number information for defining a maximum recording speed; a revision number table (application revision number); class state information and expanded (part) version information. The embodiment is featured in that the information contained from byte 28 to byte 31 include revision information according to a recording speed in a recording area of physical format information PFI or R-physical format information R_PFI. Conventionally, upon development of a medium featured in that a medium recording speed such as x 2 or x 4 increases, there has been a very complicated inconvenience that a specification is newly drafted concurrently. In contrast, according to the present embodiment, there are divisionally provided: a specification (version book) in which a version is changed when the contents have been significantly changed; and a revision book in which the corresponding revision is changed and issued, and only a revision book is issued, the book having updated only revision every time a recording speed is improved. In this manner, an expanding function for a medium which supports high speed recording and a specification can be handled by a simple method called revision change. Thus, in the case where a high speed recording compatible medium has been newly developed, there is attained advantageous effect that high speed recording can be carried out. In particular, the present embodiment is featured in that revision numbers can be separately set by a maximum value and a minimum value by separately providing a field of revision number information defining a maximum recording speed of byte 17 and a field of revision number information defining a minimum recording speed of byte 18. For example, in the case where a recording film capable of carrying out recording at a very high speed has been developed, that recording film is often very expensive. In contrast, as in the present embodiment, revision numbers are separately set depending on a maximum value and a minimum value of a recording speed, thereby increasing options of recording mediums which can be developed. As a result, there is attained advantageous effect that a medium capable of carrying out high speed recording or a more inexpensive medium can be supplied. An information recording/reproducing apparatus according to the present embodiment has in advance information on an allowable maximum recording speed and an allowable minimum recording speed for each revision. When an information storage medium is mounted on this information recording/reproducing apparatus, first, the information recording/reproducing unit 141 shown in FIG. 11 reads the information contained in this physical format information PFI and R-physical format information R_PFI. Based on the obtained revision number information, there are detected by the control unit 143: an allowable maximum speed and an allowable minimum recording speed of an information storage medium mounted with reference to information on an allowable maximum recording speed and an allowable minimum recording speed for each revision recorded in advance in the memory unit 175; and recording is carried out at an optimal recording speed based on the result of the identification. Now, a description will be given with respect to the significance of specific information 263 of the type and version of each of the specifications from byte 128 to byte 511 shown in FIG. 41 (c) and the significance of information content 264 which can be set specific to each of the revisions from byte 512 to byte 2047. That is, in the specific information 263 of type and version of each of the specifications from byte 128 to byte 511, the significance of the contents of recording information at each byte position coincides with a rewritable-type information storage medium of a different type regardless of a write-once type information storage medium. The information content 264 which can be set specific to each of the revisions from byte 512 to byte 2047 permits the fact that if a revision is different from another in the same type of medium as well as a difference between a rewritable-type information storage medium and a writeonce type information storage medium whose types are different from each other, the significances of the contents of recording information at byte positions are different from each other. As shown in FIG. 42, as information contents in the specific information 263 on the type and version of each of the specifications which coincide with each other in significance of the contents of recording information at byte positions between the rewritable-type information storage medium and the write-once type information storage medium whose types are different from each other, there are sequentially recorded: disk manufacturer's name information; additional information from the disk manufacturer; recording mark polarity information (identification of "H-L" or "L-H"); line speed information at the time of recording or reproduction; a rim intensity value of an optical system along a radial direction; and recommended laser power at the time of reproduction (light amount value on recording surface). In particular, the present embodiment is featured in that recording mark polarity information (Mark Polarity Descriptor (identification of "H-L" or "L-H") is provided in byte 192. In the conventional rewritable-type or write-once DVD disk, only a "H-L" (High to Low) recording film whose light reflection amount in a recording mark is low with respect to an unrecorded state (a state in which reflection level is relatively high: High) has been accepted. In contrast, if a medium requires "high speed recording compatibility", "price reduction" or "decrease in cross-erase" and "increase in upper limit value of rewriting count" which are physical properties, there is a problem that the conventional "H-L" recording film is insufficient. In contrast, the present embodiment allows use of an "L-H" recording film whose light reflection amount increases in a recording mark as well as only an "H-L" recording film. Thus, there is attained advantageous effect that the "L-H" recording film as well as the conventional "H-L" film is incorporated in the specification, and selecting options of the recording films are increased, thereby making it possible to achieve high speed recording or to supply an inexpensive medium. A specific method for mounting an information recording/reproducing apparatus will be described below. The specification (version book) or revision book describe both of the reproduction signal characteristics derived from the "H-L" recording film and the reproduction signal characteristics derived from the "L-H" recording film. Concurrently, the corresponding circuits are provided on a two by two basis in the PR equalizing circuit 130 and Viterbi decoder 156 shown in FIG. 11. When an information storage medium is mounted in the information reproduction unit 141, first, the slice level detector circuit 132 for reading the information contained in the system lea-in area SYLDI is started up. This slice level detector circuit 132 reads information on polarity of a recording mark recorded in this 192 byte (identification of "H-L" or "L-H"); and then make judgment of "H-L" or "L-H". In response to the judgment, after the PR equalizing circuit 130 and a circuitry contained in the Viterbi decoder 156 has been switched, the information recorded in the data lead-in area DTLDI or data area DTA is reproduced. The above described method can read the information contained in the data lead-in area DTLDI or data area DTA comparatively quickly, and moreover, precisely. Although revision number information defining a maximum recording speed is described in byte 17 and revision number information defining a minimum recording speed is described in byte 18, these items of information are merely provided as range information defining a maximum and a minimum. In the case where the most stable recording is carried out, there is a need for optimal line speed information at the time of recording, and thus, the associated information is recorded in byte 193. The present embodiment is featured in that information on a rim intensity value of an optical system along a circumferential direction of byte 194 and information on a rim intensity value of an optical system along in a radial direction of byte 195 is recorded as optical system condition information at a position which precedes information on a variety of recording conditions (write strategies) included in the information content 264 set specific to each revision. These items of information denote conditional information on an optical system of an optical head used when identifying a recording condition arranged at the back side. The rim intensity used here denotes a distribution state of incident light incident to an objective lens before focusing on a recording surface of an information storage medium. This intensity is defined by a strength value at a peripheral position of an objective lens (iris face outer periphery position) when a center intensity of an incident light intensity distribution is defined as "1". The incident light intensity distribution relevant to an objective lens is not symmetrical on a point to point basis; an elliptical distribution is formed; and the rim intensity values are different from each other depending on the radial direction and the circumferential direction of the information storage medium. Thus, two values are recorded. As the rim intensity value increases, a focal spot size on a recording surface of the information storage medium is reduced, and thus, an optimal recording power condition changes depending on this rim intensity value. The information recording/reproducing apparatus recognizes in advance the rim intensity value information contained in its own optical head. Thus, this apparatus reads the rim intensity values of the optical system along the circumferential direction and the radial direction, the value being recorded in the information storage medium, and compares values of its own optical head. If there is no large difference as a result of the comparison, a recording condition recorded at the back side can be applied. If there is a large difference, there is a need for ignoring the recording condition recorded at the back side and starting identifying an optimal recording condition while the recording/reproducing apparatus carries out test writing by utilizing the drive test zone DRTZ shown in FIGS. 35B, 35C, 37A to 37F. Therefore, there is a need for quickly making a decision as to whether to utilize the recording condition recorded at the back side or whether to start identifying the optimal recording condition while ignoring the information and carrying out test writing by oneself. As shown in FIG. 42, there is attained advantageous effect that the rim intensity information can be read, and then judgment can be made at a high speed as to whether or not the receding condition arranged later is met by arranging conditional information on an optical system identified at a preceding position with respect to a position at which the recommended recording condition has been recorded. As described above, according to the present embodiment, there are divisionally provided: a specification (version book) in which a version is changed when the contents have been significantly changed; and a revision book in which the corresponding revision is changed and issued, and only a revision book is issued, the book having updated only revision every time a recording speed is improved. Therefore, if a revision number is different from another, a recording condition in a revision book changes. Thus, information relating to a recording condition (write strategy) is mainly recorded in the information content 264 which can be set specific to each of the revisions from byte 512 to byte 2047. As is evident from FIG. 42, the information content 264 which can be set specific to each of the revisions from byte 512 to byte 2047 permits the fact that if a revision is different from another in the same type of medium as well as a difference between a rewritable-type information storage medium and a write-once type information storage medium whose types are different from each other, the significances of the contents of recording information at byte positions are different from each other. Definitions of peak power, bias power 1, bias power 2, and bias power 3 shown in FIG. 42 coincide with power values defined in FIG. 18. An end time of a first pulse shown in FIG. 42 denotes Tgjrp defined in FIG. 18; a multi-pulse interval denotes Tjyjp defined in FIG. 18; a start time of a last pulse denotes TgLp defined in FIG. 38, and a period of bias power 2 of 2T mark denotes T^c defined in FIG. 18. FIG. 54 shows another embodiment relating to a data structure in each of physical format information and R-physical format information. Further, FIG. 54 comparatively describes "updated physical format information". In FIG. 54, byte 0 to byte 31 are utilized as a recording area of common information 269 contained in a DVD family, and byte 32 and subsequent are set for each specification. In a write-once type information storage medium, as shown in FIG. 35C, with respect to R-physical format information recorded in an R-physical information zone RIZ contained in the data lead-in area DTLDI, border zone start position information (first border outermost periphery address) is added to the physical format information PFI (copy of HD_DVD family common information), and the added information is described. In the updated physical format information U_PFI, updated in the border-in area BRDI shown in FIG. 40 or 39, start position information (self-border outermost periphery address) is added to the physical format information (copy of HD_DVD family common information), and the added information is recorded. In FIG. 42, this border zone start position information is recorded from byte 197 to byte 204. In contrast, the embodiment shown in FIG. 54 is featured in that information is recorded at byte 133 to byte 140 which are positions preceding information relating to a recording condition such as peak power or bias power 1 (information content 264 which can be set specific to each revision), the position following the common information 269 contained in the DVD family. The updated start position information is also arranged in byte 133 to byte 140 which are positions preceding information relating to a recording condition such as peak power or bias power 1 (information content 264 which can be set specific to each revision), the position following the common information 269 contained in the DVD family. If revision number is upgraded and a recording condition for high precision is required, there is a possibility that the recording condition information contained in the rewritable-type information storage medium uses byte 197 to byte 207. In this case, as in the embodiment shown in FIG. 42, if the border zone start position information for R-physical format information recorded in the write-once type information storage medium is arranged in byte 197 to byte 204, there is a danger that a correlation (compatibility) between the rewritable-type information storage medium and the write-once type information storage medium relating to the arranged position of the recording condition is distorted. As shown in FIG. 54, there is attained advantageous effect that the border zone start position information and the updated start position information are arranged in byte 133 to byte 140, thereby making it possible to record a correlation (compatibility) in recording position of a variety of information between the rewritable-type information storage medium and the write-once type information storage medium even if an amount of information relating to a recording condition will be increased in the future. With respect to the specific contents of information relating to the borer zone start position information, the start position information on the border out area BRDO situated at the outside of the (current) bordered area BRDA currently used in byte 133 to byte 136 is described in PSN (Physical Sector Number); and border-in area BRDI start position information relating to the bordered area BRDA to be used next is described in the physical sector number (PSN) in byte 137 to byte 140. The specific contents of information relating to the updated start position information indicate the latest border zone position information in the case where a bordered area BRDA has been newly set. The start position information on the border out area BRDO situated at the outside of the (current) bordered area BRDA currently used in byte 133 to byte 136 is described in PSN (Physical Sector Number); and the start position information on the border-in area BRDI relating to the bordered area BRDA to be used next is described in the sector number (PSN) in byte 137 to byte 140. In the case where recording cannot be carried out in the next bordered area BRDA, this area (ranging from byte 137 to byte 140) is padded with all "OOh". As compared with the embodiment shown in FIG. 42, in the embodiment shown in FIG, 54, "medium manufacturer's name information" and "additional information from medium manufacturer" are erased, and recording mark polarity information (identification of "H-L" or "L-H") is arranged in 128 byte and subsequent. FIG. 43 shows a comparison of the contents of detailed information recorded in the allocation location information on the data area DTA recorded in byte 4 to byte 15 shown in FIG. 42 or 54. The start position information on the data area DTA is recorded in common regardless of identification of medium type, physical format information PFI, and R-physical format information R_PFI. As information indicating an end position, end position information on the data area DTA is recorded in a read-only type information storage medium. End position information on an additional writing enable range of the user data is recorded in the physical format information PFI contained in the writeonce type storage medium. This positional information denotes a position that immediately precedes point 5 in an example shown in FIG. 37E, for example. In contrast, the R-physical format information R_PFI contained in the write-once type information storage medium records the end position information on the recorded data contained in the corresponding bordered area BRDA. Further, the read-only type information storage medium records the end address information contained in "layer 0" which is a front layer when seen from the reproduction optical system; and the rewritable-type information storage medium records information on a differential value of each item of start position information between a land area and a groove area. As shown in FIG. 35C, a recording management zone RMZ exists in the data lead-in area DTLDI. In addition, as shown in FIG. 40 (d), the associated copy information exists in the border-out zone BRDO as copy information C_RMZ indicating the contents recorded in the recording management zone. This recording management zone RMZ records RMD (Recording Management Data) having the same data size as one physical segment block size, as shown in FIG. 36 (b), so that new recording management data RMD updated every time the contents of the recording management data RMD is updated can be sequentially added backwardly. A detailed data structure in such one item of recording management data RMD is shown in each of FIGS. 44, 45, 46, 47, 48 and 49. The recording management data RMD is further divided into fine RMD field information RMDF of 2048 byte size. The first 2048 bytes in the recording management data are provided as a reserved area. The next RMD field 0 of 2048 byte size sequentially allocates: format code information of recording management data RMD; medium state information indicating a state of the target medium, i.e., (1) in an unrecorded state, (2) on the way of recording before finalizing, or (3) after finalizing; unique disk ID (disk identification information); allocation position information on the data region DTA; allocation position information on the latest (updated) data area DTA; and allocation position information on recording management data RMD. The allocation position information on the data area records information indicating a user data additional writing enable range 204 (FIG. 37D), i.e., start position information on the data area DTA and the end position information on the user data recording enable range 204 at the time of an initial state. In the embodiment shown in FIG. 37D, this information indicates a position that immediately precedes point p. The present embodiment, as shown in FIGS. 37E and 37F, is featured in that an expanded drive test zone EDRTZ and an expanded spare area ESPA can be additionally set in the user data additional writing enable range 204. However, such expansion narrows a user data additional writing enable range 205. The present embodiment is featured in that associated information is recorded in "allocation position information on the latest (updated) data area DTA" so as not to additionally write the user data in these expanded areas EDRTZ and ESPA. That is, it is possible to identify whether or not the expanded drive test zone EDRTZ has been expanded based on the identification information on the presence or absence of the expanded drive test zone EDRTZ, and it is possible to identify whether or not the expanded spare area ESPA has been expanded based on identification information on the presence or absence of the expanded spare area ESPA. Further, the recording enable range information relating to the user data additional writing enable range 205 managed in the recording management data RMD includes an end position of the latest user data recording enable range 205 recorded in the allocation position information on the data area DTA. Therefore, the user data recording enable range 205 shown in FIG. 37F can be identified immediately, enabling high speed detection of a size of an unrecorded area in which recording can be carried out in the future (the residual amount of unrecorded area). In this manner, for example, there is attained advantageous effect that a transfer rate at the time of optimal recording is set in conformance with the user specified image recording reserved time, thereby making it possible to fully record an image in a medium during the user specified image recording reserved time. By way of example of the embodiment shown in FIG. 37D, "the end position of the latest user data recording enable range 205" denotes a position that precedes point 8. These items of positional information can be described in ECC block address numbers according to another embodiment instead of being described in physical sector numbers. As described later, in the present embodiment, one ECC block is composed of 32 sectors. Therefore, the least significant five bits of the physical sector number of a sector arranged at the beginning in a specific ECC block coincides with that of a sector arranged at the start position in the adjacent ECC block. In the case where a physical sector number has been assigned so that the least significant five bits of the physical sector of the sector arranged at the beginning in the ECC block is "00000", the values of the least significant six bits or more of the physical sector numbers of all the sectors existing in the same ECC block coincide with each other. Therefore, address information obtained by eliminating the least significant five bit data of the physical sector numbers of the sectors existing in the same ECC block as above and sampling only data of the least significant six bit and subsequent is defined as ECC block address information (or ECC block address number). As described later, the data segment address information (or physical segment block number information recorded in advance by wobble modulation coincides with the above ECC block address. Thus, when the positional information contained in the recording management data RMD is described in the ECC block address numbers, there is attained advantageous effects described below: 1) An access to an unrecorded area is accelerated in particular: - A differential calculation process is facilitated because a positional information unit of the recording management data RMD coincides with an information unit of data segment addresses recorded in advance by wobble modulation; and 2) A management data size in the recording management data RMD can be reduced: - The number of bits required for describing address information can be reduced by 5 bits per address. As described later, a single physical segment block length coincides with a one data segment length, and the user data for one ECC block is recorded in one data segment. Therefore, an address is expressed as an "ECC block address number"; an "ECC block address"; a "data segment address", a "data segment number", or a "physical segment block number" and the like. These expressions have the same meaning. As shown in FIG. 44, in the allocation position information on the recording management data RMD existing in RMD field 0, size information in that the recording management zone RMZ capable of sequentially additionally writing the recording management data RMD is recorded in ECC block units or in physical segment block units. As shown in FIG. 36 (b), one recording management zone RMD is recorded on one by one physical segment block basis, and thus, based on this information, it is possible to identify how many times the updated recording management data RMD can be additionally written in the recording management zone RMZ. Next, a current recording management data number is recorded in the recording management zone RMZ. This denotes number information on the recording management data RMD which has been already recorded in the receding management zone RMZ. For example, assuming that this information corresponds to the information contained in the recording management data RMD#2 as an example shown in FIG. 36 (b), this information corresponds to the second recorded recording management data RMD in the receding management zone RMZ, and thus, a value "2" is recorded in this field. Next, the residual amount information contained in the recording management zone RMZ is recorded. This information denotes information on the item number of the recording management data RMD which can be further added in the recording management zone RMZ, and is described in physical segment block units (= ECC block units = data segment units). Among the above three items of information, the following relationship is established. [Size information having set RMZ therein] = [Current recording management data number] + [residual amount in RMZ] The present embodiment is featured in that the use amount or the residual amount information on the recording management data RMD contained in the recording management zone RMZ is recorded in a recording area of the recording management data RMD. For example, in the case where all information is recorded in one write-once type information storage medium once, the recording management data RMD may be recorded only once. However, in the case where an attempt is made to repeatedly record additional writing of the user data (additional writing of the user data in the user data additional writing enable range 205 in FIG. 37F) very finely in one write-once type information storage medium, it is necessary to additionally write recording management data RMD updated every time additional writing is carried out. In this case, if the recording management data RMD is frequently additionally written, the reserved area 273 shown in FIG. 36 (b) is eliminated, and the information recording/reproducing apparatus requires countermeasures against this elimination. Therefore, the use amount or residual amount information on the recording management data RMD contained in the recording management zone RMZ is recorded in a recording area of the recording management data RMD, thereby making it possible to identify in advance a state in which additional writing in the recording management zone RMZ cannot be carried out and to take action by the information recording/reproducing apparatus earlier. As shown in FIGS. 37E to 37F, the present embodiment is featured in that the data lead-out area DTLDO can be set in the form such that the expanded drive test zone EDRTZ is included (FIG. 1 (E4)). At this time, the start position of the data lead-out area DTLDO changes from point P to point £. In order to manage this situation, there is provided a field for recording the start position information on the data lead-out area DTLDO in the allocation position information of the latest (updated) data area DTA of the RMD field shown in FIGS. 44 to 49. As described previously, a drive test (test writing) is basically recorded in cluster units which can be expanded in data segment (ECC block) units. Therefore, although the start position information on the data lead-out area DTLDO is described in the ECC block address numbers, this information can be described in the physical sector number or physical segment block number, data segment address, or ECC block address of a physical sector first arranged in this first ECC block according to another embodiment. In an RMD field 1, there are recorded: update history information on an information recording/reproducing apparatus in which recording of the corresponding medium has been carried out. This information is described in accordance with a format of all recording condition information contained in information 264 (FIG. 42) in which manufacturer identification information for each information recording/reproducing apparatus; serial numbers and model numbers described in ASCII codes; date and time information when recording power adjustment using a drive test zone has been made; and recording condition information provided at the time of additional writing can be set specific to each revision. An RMD field 2 is a user available area so that a user can record information recorded contents (or contents to be recorded), for example. The start position information of each border zone BRDZ is recorded in an RMD field 3. That is, as shown in FIG. 45, the start position information from the start to the fiftieth border out areas BTDOs is described in the physical sector numbers. For example, in the embodiment shown in FIG. 40 (c), the start position of the first border out area BRDO indicates a position of point r\|, and the start position of the second BRDO indicates a position of point 9. The positional information on an expanded drive test zone is recorded in an RMD field 4. First, there are recorded: the end position information on a location which has already been used for test writing in the drive test zone DRTZ which exists in the data lead-in area DTLDI described in FIG. 36 (c); and the end position information on a location which has already been used for test writing in the drive test zone DRTZ which exists in the data lead-out area DTLDO described in FIGS. 37D to 37F. In the drive test zone DRTZ, the above position information is sequentially used for test writing from the inner periphery side (from the lowest physical sector number) to the outer periphery direction (in a direction in which the physical sector number is higher). Test writing is carried out in cluster units which are units of additional writing, as described later, and thus, ECC block units are used as location units. Therefore, in the case where the end position information on the location which has been already used for test writing is described in the ECC address numbers or is described in the physical sector numbers, there are described a physical sector number of a physical sector arranged at the end of the ECC block which has been used for test writing. Because a location used for test writing once has already been described, in the case where next test writing is carried out, such test writing is carried out from a next of the end position which has already been used for test writing. Therefore, the information recording/reproducing apparatus can identify momentarily from where test writing should be started by using the end position information (= a use amount in the drive test zone DRTZ) on a location which has already been used in the above drive test zone DRTZ. In addition, based on that information, this apparatus can judge whether or not a free space in which next test writing can be carried out exists in the drive test zone DRTZ. The drive test zone DRTZ which exists in the data lead-in area DTLDI records: flag information indicating whether or not area size information indicating that additional writing can be carried out; flag information indicating that this drive test zone DRTZ has been used up or area size information indicating that additional test writing can be further carried out in the drive test zone DRTZ which exists in the data lead-out area DLTDI; and area size information indicating that additional test writing can further be carried out in the drive test zone DRTZ which exists in the data lead-out area DTLDO or flag information indicating whether or not this drive test zone DRTZ has been used up. The size of the drive test zone DRTZ which exists in the data lead-in area DTLDI and the size of the drive test zone DRTZ which exists in the data lead-out area DTLDO are identified in advance, thus making it possible to identify the size (residual amount) of an area in which additional test writing can be carried out in the drive test zone DRTZ only based on the end position information on a location which has already been used for test writing in the drive test zone DRTZ which exists in the data lead-in area DTLDI or in the drive test zone DRTZ which exists in the data lead-out area DTLDO. However, this information is provided in the recording management data RMD, thereby making it possible to identify the residual amount in the drive test zone DRTZ immediately and to reduce a time required for judging whether or not to newly set the expanded drive test zone EDRTZ. According to another embodiment, in this field, it is possible to record: flag information indicating whether or not this drive test zone DRTZ has been used up instead of area size (residual amount) information indicating that additional writing can further be carried out in the drive test zone DRTZ. If a flag has already been set to identify momentarily that the above test zone has already been used up, it is possible to preclude a danger that test writing is carried out in this area. Additional setting count information on the next expanded drive test zone EDRTZ is recorded in the RMD field 4. In the embodiment shown in FIG. 37E, the expanded drive test zones EDRTZs are set in two zones, i.e., an expanded drive test zone 1 EDRTZl and an expanded drive test zone 2 EDRTZ2, and thus, "additional setting count of the expanded drive test zone EDRTZ = 2" is established. Further, range information for each expanded drive test zone EDRTZ and range information which has already been used for test writing are recorded in the RMD field 4. In this way, the positional information on the expanded drive test zone can be managed in the recording management data RMD, thereby enabling expansion setting of the expanded drive test zone EDRTZ a plurality of times. In addition, in a write-once type information storage medium, the positional information on the expanded drive test zone EDRTZ which has been sequentially expanded can be precisely managed in the form of updating and additional writing of the recording management data RMD, and it is possible to preclude a danger that the user data is overwritten on the expanded drive test zone EDRTZ while user data additional writing enable range 204 (FIG. 37D) is mistakenly determined. As described above, test writing units are also recorded in cluster units (ECC block units), and thus, the range of each expanded drive test zone EDRTZ is specified in ECC block address units. In the embodiment shown in FIG. 37E, the start position information on the first set expanded drive test zone EDRTZ indicates point y because the expanded drive test zone 1 EDRTZl has been first set; and the end position information on the first set expanded drive test zone EDRTZ corresponds to a position that immediately precedes point p. Positional information units are described in the address numbers or physical sector numbers similarly. While the embodiment of FIGS. 44 and 45 shows the end position information on the expanded drive test zone EDRTZ, size information on the expanded drive test zone EDRTZ may be described without being limited thereto. In this case, the size of the first set expanded drive test zone 1 EDRTZl is set to "p-y". The end position information on a location which has already been used for test writing in the first set expanded drive test zone EDRTZ is also described with the ECC block address number or physical sector number. Then, the area size information (residual amount) in which additional test writing can be carried out in the first set expanded drive test zone EDRTZ. The size of the expanded drive test zone 1 EDRTZl and the size of the area, which has already been used therein, is already been identified based on the above described information. Thus, the area size (residual amount) in which additional test writing can be carried out is already obtained. By providing this field, it is possible to identify immediately whether or not a current drive test zone will suffice when a new drive test (test writing) is carried out. In addition, it is possible to reduce a judgment time required for determining additional setting of a further expanded drive test zone EDRTZ. In this field, there can be recorded area size (residual amount) information indicating that additional writing can be carried out. According to another embodiment, in this field it is possible to set flag information indicating whether or not this expanded drive test zone EDRTZ has been used up. It is possible to preclude a danger that test writing is mistakenly carried out in this area, as long as a flag is set to momentarily identify that the test zone has already been used up. A description will be given with respect to an example of a processing method for newly setting an expanded drive test zone EDRTZ by the information recording/reproducing apparatus shown in FIG. 11 and carried out test writing in the zone. 1) A write-once type information storage medium is mounted on an information recording/reproducing apparatus. 2) Data formed in the burst cutting area BCA is reproduced by the information recording/reproducing unit 141; the recorded data is supplied to the control unit 143; and the information is decoded in the control unit 143, and it is determined whether or not processing can proceeds to a next step. 3) Information recorded in the control data zone CDZ in the system lead-in area SYLDI is recorded by the information recording/reproducing unit 141, and the reproduced information is transferred to the control unit 143. 4) Values of rim intensities (in bytes 194 and 195 shown in FIG. 42) when a recommended recording condition has been identified in the control unit 143 are compared with a value of rim intensity of an optical head used at the information recording/reproducing unit 141; and an area size required for test writing is identified. 5) The information contained in recording management data is reproduced by the information recording/reproducing unit 141, and the reproduced information is transferred to the control unit 143. The control section decodes the information contained in the RMD field 4 and determines whether or not there is a margin of an area size required for test writing, the size being identified in step 4). In the case where the judgment result is affirmative, processing proceeds to step 6). Otherwise, processing proceeds to step 9). 6) A location for starting test writing is identified based on end position information on a location which has already been used for test writing in the drive test zone DRTZ or expanded drive test zone EDRTZ used for test writing from the RMD field 4. 7) Test writing is executed by the size identified in step 4) from the location identified in step 6). 8) The number of locations used for test writing has been increased in accordance with the processing in step 7), and thus, recording management data RMD obtained by rewriting the end position information on the locations which has already been used for test writing is temporarily stored in the memory unit 175, and processing proceeds to step 12). 9) The information recording/reproducing unit 141 reads information on "end position of the latest user data recording enable range 205" recorded in the RMD field 0 or "end position information on the user data additional writing enable range" recorded in the allocation location information on the data area DTA contained in the physical formed shown in FIG. 43; and the control unit 143 further internally sets the range of a newly set expanded drive test zone EDRTZ. 10) Information on "end position of the latest used data recording enable range 205" recorded in the RMD field 0 based on the result described in step 9) is updated and additional setting count information on the expanded drive test zone EDRTZ contained in the RMD field 4 is incremented by one (that is, the count is added by 1); and further, the memory unit 175 temporarily stores the recording management data RMD obtained by adding the start/end position information on the newly set expanded drive test zone EDRTZ. 11) Processing moves from step 7) to step 12). 12) Required user information additionally written into the user data additional writing enable range 205 under an optimal recording condition obtained as a result of test writing carried out in step 7). 13) The memory unit 175 temporarily stores the recording management data RMD updated by additionally writing the start/end position information (FIG. 47) contained in an R zone which has been newly generated in response to step 12). 14) The control unit 143 controls the information recording/reproducing unit 141 to additionally record the latest recording management data RMD temporarily stored in the memory unit 175, in the reserved area 273 (for example, FIG. 36 (b)) contained in the recording management zone RMZ. As shown in FIG. 47, positional information on the expanded spare area ESPA is recorded in an RMD field 5. In the write-once type information storage medium, a spare area can be expanded, and the positional information on that spare area is managed in the position management data RMD. In the embodiment shown in FIG. 37E, the expanded spare area ESPA is set in two areas, i.e., an expanded spare area 1 ESPA1 and an expanded spare area 2 ESPA2, and thus, "the number of additional settings of the expanded space area ESPA" is set to "2". The start position information on the first set expanded spare area ESPA corresponds to at a position of point 8; the end position information on the second set expanded spare area ESPA corresponds to at a position that precedes point y; the end position information on the first set expanded spare area ESPA corresponds to at a position that precedes point £; and the end position information on the second set expanded spare area ESPA corresponds to at a position of point E. The information relating to defect management is recorded in the RMD field 5 shown in FIG. 47. A first field in the RMD field 5 shown in FIG. 47 records ECC block number information or physical segment block number information which has already been used for substitution in the adjacent area to the data lead-in area DTLDI. In the present embodiment, a substituting process is carried out in ECC block units with respect to a defect area found in the user data additional writing range 204. As described later, one data segment configuring one ECC block is recorded in one physical segment block area, and thus, the substitution count which has already been done is equal to the number of ECC blocks which has already been used (or number of physical segment blocks and number of data segments). Therefore, the units of information described in this field are obtained as ECC block units or physical segment block units and data segment units. In the write-once type information storage medium, in the spare area SPA or expanded pare area ESPA, a location used as a replacing process may be often used sequentially from the inner periphery side having the lowest ECC block address number. Therefore, with respect to the information contained in this field, in another embodiment, it is possible to describe an ECC block address number as the end position information on a location which has already been used for substitution. As shown in FIG. 47, with respect to the first set expanded spare area 1 ESPA1 and the second set expanded spare area 2 ESPA2 as well, there exist fields for recording similar information ("ECC block number information or physical segment block number information which have already been used for substitution in the first set expanded spare area ESPA or end position information (ECC block address number) on a location which has been used for substitution"; and "ECC block number information or physical segment block number information which have already been used for substitution in the second set expanded spare area ESPA or end position information (ECC block address number) on a location which has been used for substitution". Using these items of information, the following advantageous effects are attained: 1) A spare location to be newly set with respect to a defect area found in the user data additional writing enable range 205 is identified immediately when next substituting process is carried out. - New substitution is carried out immediately after the end position of a location which has already been used for substitution. 2) The residual amount in the spare area SPA or expanded spare area ESPA is obtained by calculation and (in the case where the residual amount is insufficient) , it is possible to identify necessity of setting a new expanded spare area ESPA. The size of the spare area SPA adjacent to the data lead-in area DTLDI is identified in advance, and thus, the residual amount in the spare area SPA can be calculated if there exists information relating to the number of ECC blocks which have already been used in the spare area SPA. However, the residual amount can be identified immediately by providing a recording frame of the ECC block number information or physical segment block number information in an unused location available for future substitution, which is residual amount information contained in the spare area SPA. Thus, it is possible to reduce a time required for judgment of the necessity of providing settings relating to a further expanded spare area ESPA. For a similar reason, there is provided a frame capable of recording "residual amount information contained in the first set expanded spare area ESPA and "residual amount information contained in the second set expanded spare area ESPA. In the present embodiment, a spare area SPA is extensible in the write-once type information storage medium, and the associated position information is managed in the recording management data RMD. As shown in FIGS. 37A to 37F, it is possible to extensively set an expanded spare area 1 ESPA1 and an expanded spare area 2 ESPA2 or the like at an arbitrary start position and at an arbitrary size as required in the user data additional writing enable range 204. Therefore, the additional setting count information on the expanded spare area ESPA is recorded in the RMD field 5, making it possible to set the start position information on the first set expanded spare area ESPA or the start position information on the secondly set expanded spare area ESPA. These items of start position information are described in physical sector numbers or ECC block address numbers (or physical segment block numbers or data segment addresses). In the embodiment shown in FIGS. 44 and 45, "the end position information on the first set expanded spare area ESPA" or "the end position information on the second set expanded spare area ESPA" are recorded as information for specifying the range of the expanded spare area ESPA. However, in another embodiment, in stead of these items of end position information, size information on the expanded spare area ESPA can be recorded by the ECC block number or physical segment block number, data segment number, and ECC block number or physical sector number. Defect management information is recorded in an RMD field 6. The present embodiment uses a method for improving reliability of information to be recorded in an information storage medium, the information relating to defect processing, in the following two modes: 1) A conventional "replacing mode" for recording in a spare location information to be recorded in a defect location; and 2) A "multiplying mode" for recording the same contents of information twice in a location which is different from another one on an information storage medium, thereby improving reliability. Information as to which mode processing is carried out is recorded in "type information on defect management processing" contained in secondary defect list entry information contained in the recording management data RMD as shown in FIG. 48. The contents of secondary defect list entry information are as follows: 1) In the case of the conventional replacing mode Type information on defect management processing is set to "01" (in the same manner as in conventional DVD-RAM); The "positional information on a replacement source ECC block" used here denotes positional information on an ECC block found as a defect location in the user data additional writing enable range 205, and information to be essentially recorded in the range is recorded in a spare area or the like without being recorded in the above range; and The "positional information on a replacement destination ECC block" used here indicates positional information on a location of a replacement source to be set in the spare area SPA or expanded spare area I ESPA1, and an expanded spare area 2 ESPA2 shown in FIG. 37E, and the information to be recorded in a defect location, the information being found in the additional writing enable range 205, is recorded in the above area. 2) In the case of the multiplying mode Type information on defect management processing is set to "10"; The "positional information on replacement source ECC block" denotes a non-defect location, and indicates position information in which target information is recorded and the information recorded therein can be precisely reproduced; and The "positional information on replacement destination ECC block" indicates positional information on a location in which the completely same contents as the information recorded in the above described "positional information on replacement source ECC block" are recorded for the purpose of multiplication set in the spare area SPA or expanded spare area 1 ESPA1 and expanded spare area 2 ESPA 2 shown in FIG. 37E. In the case where recording has been carried out in the above described "1) conventional replacing mode", it is confirmed that the information recorded in an information storage medium is precisely read out at the stage immediately after recording. However, there is a danger that the above described information cannot be reproduced due to scratch or dust adhering to an information storage medium, caused by the user's abuse. In contrast, in the case where recording has been carried out in the "2) multiplying mode", even if information cannot be partially read in an information storage medium due to a scratch or dust caused by user's abuse or the like, because the same information is backed up at another portion, the reliability of information reproduction is remarkably improved. The above backed up information is utilized for the information which cannot be read at this time, and the replacing process in "1) conventional replacing mode" is carried out, thereby further improving reliability. Therefore, there is attained advantageous effect that high reliability of information reproduction after recorded, considering countermeasures against scratch or dust can be arranged by a processing operation in "1) conventional replacing mode" alone and by using a combination of the processing operation in "1) conventional replacing mode" and a processing mode in "2) multiplying mode". Methods for describing the positional information on the above ECC block include: a method for describing a physical sector number of a physical sector which exists at a start position which configures the above ECC block and a method for describing an ECC block address, a physical segment block address, or a data segment address. As described later, in the present embodiment, a data area including data of one ECC block size is referred to as a data segment. A physical segment block is defined as a physical unit on an information storage medium serving as a location for recording data, and one physical segment size coincides with a size of an area for recording one data segment. The present embodiment provides a mechanism capable of recording the defect position information detected in advance before the replacing process. In this manner, the manufacturers of information storage mediums check a defect state in the user data additional writing range 204 immediately before shipment. When the detected defect location is recorded in advance (before the replacing process) or the information recording/reproducing apparatus has carried out an initializing process at the user's site, the defect state in the user data additional writing enable range 294 is checked so that the detected defect location can be recorded in advance (before the replacing process). In this way, the information indicating a defect position detected in advance before the replacing process corresponds to "information on the presence or absence of the process for replacing a defect block with a spare block" (SLR: State of Linear Replacement) contained in the secondary defect list entry information. When the information SLR on the presence or absence of the process for replacing a defect block with a spare block is set to "0": - The replacing process is carried out with respect to a defect ECC block specified by "positional information on replacement source ECC block"; and Information, which can be reproduced, is recorded in a location specified by "positional information on replacement destination ECC block". When the information SLR on the presence or absence of the process for replacing a defect block with a spare block is set to "1": - A defect ECC block specified by "positional information on replacement source ECC block" denotes a defect block detected in advance at the state that precedes the replacing process; and A field of "positional information on replacement destination ECC block" is blanked (no information is recorded). When a defect location is thus identified in advance, there is attained advantageous effect that an optimal replacing process can be carried out at a high speed (and in a real time) at the stage at which an information recording/reproducing apparatus carries out additional writing in a write-once type information storage medium. In addition, in the case where video image information or the like is recorded in the information storage medium, it is necessary to guarantee continuity at the time of recording, and a high speed replacing process based on the above described information becomes important. If a defect occurs in the user data additional writing enable range 205, the replacing process is carried out in predetermined location placed in the spare area SPA or expanded spare area ESPA. Every time the replacing process is carried out, one item of Secondary Defect List Entry information is added; and set information on the positional information on an ECC block utilized as a substitute of the positional information on a defect ECC block is recorded in this RMD field 6. When additional writing of the user data is newly repeated in the user data additional writing enable range 205, if a new defect location is detected, the replacing process is carried out, and the number of items of the secondary defect list entry information increases. A management information area (RMD field 6) for defect management can be expanded by additionally writing the recording management data RMD with an increased number of items of this Secondary Defect List Entry information into the reserved area 273 contained in the recording management zone RMZ, as shown in FIG. 36 (b). By using this method, the reliability of defect management information itself can be improved for the reasons described below. 1) The recording management data RMD can be recorded while avoiding a defect location in the recording management zone RMZ. - A defect location may be produced in the recording management zone RMZ shown in FIG. 36 (b). The contents of the recording management data RMD newly additionally written in the recording management zone RMZ are verified immediately after additional writing, thereby making it possible to sense a state in which recording cannot be carried out due to a defect. In that case, the recording management data RMD is rewritten adjacent to the defect location, thereby making it possible to record the recording management data RMD in the form such that high reliability is guaranteed. 2) Even if the past recording management data RMD cannot be reproduced due to the scratch adhering to an information storage medium surface, a certain degree of backup can be carried out. - For example, in the case where the example shown in FIG. 36 (b) is taken, a state in which, after recording management data RMD#2 has been recorded, the information storage medium surface is scratched due to the user's mistake or the like, and then, the recording management data RMD#2 cannot be reproduced, is presumed as an example. In this case, a certain degree of the past defect management information (information contained in the RMD field 6) can be recovered by reproducing information on the recording management data RMD#1 instead. Size information on the RMD field 6 is recorded at the beginning of the RMD field 6, and this field size is made variable, thereby making it possible to expand the management information area (RMD field 6) for defect management. Each RMD field is set to 2048 size (for one physical sector size), as described previously. However, if a plenty of defects occur with the information storage medium, and then, the replacing process count increases, the size of the Secondary Detect List information increases, and the 2048 byte size (for one physical sector size) becomes insufficient. In consideration of this situation, the RMD field 6 can be set to a plurality of multiples of 2048 size (recording across a plurality of sectors can be carried out). Namely, if "the size of the RMD field 6" has exceeded 2048 bytes, an area for a plurality of physical sectors is arranged to the RMD field 6. The secondary defect list information SDL records: the secondary defect list entry information described above; "secondary defect list identification information" indicating a start position of the secondary defect list information SDL; and "secondary defect list update counter (update count information)" indicating count information as to how many times the secondary defect list information SDL has been rewritten. The data size of the whole secondary defect list information SDL can be identified based on "number information on the secondary defect list entry". As described previously, user data recording is locally carried out in units of R zone in the user data additional writing enable range 205. That is, part of the user data additional writing enable range 205 reserved for receding the user data is referred to as an R zone. This R zone is divided into two types according to a recording condition. Among them, a type of zone in which additional user data can be further recorded is referred to as an Open R Zone, and a type of zone in which no further user data can be added is referred to as a Complete R Zone. The user data additionally writing enable range 205 cannot have three or more Open R zones. That is, up to two Open R zones can be set in the user data additional writing enable range 205. A location in which either of the above two types of R zones are not set in the user data additional writing enable range 205, i.e., a location in which the user data is reserved to record the user data (as either of the above two types of R zones), is referred to as an unspecified R zone (Invisible R Zone). In the case where the user data is fully recorded in the user data additional writing enable range 205, and then, no data can be added, this Invisible R zone does not exist. Up to 254-th R zone position information is recorded in an RMD field 7. The "whole R zone number information" first recorded in the RMD field 7 denotes a total number totalizing the number of Invisible R Zone logically established in the user data additional writing enable range 205, Open R Zones and the number of Complete R Zones. Next, the number information on the first Open R zone and the number information on the second Open R zones are recorded. As described previously, the user data additional writing enable range 205 cannot have three or more Open R zones, and thus, "1" or "0" is recorded (in the case where the first or second Open R zone does not exist). Next, the start position information and the end position information on the first Complete R zone are described in physical sector numbers. Then, the second to 254th start position information and end position information are sequentially described in the physical sector numbers. In an RMD field 8 and subsequent, the 255-th and subsequent start position information and end position information are sequentially described in the physical sector numbers, and a maximum of RMD fields 15 (a maximum of 2047 Complete R zones) can be described according to the number of Complete R Zones. FIGS. 51 and 52 each show another embodiment with respect to a data structure in the recording management data RMD shown in FIGS. 44 to 49. In the embodiment shown in FIGS. 51 and 52, up to 128 bordered areas BRDAs can be set on one write-once type information storage medium. Therefore, the start position information on the first to 128 border out areas BRDOs is recorded in the RMD field 3. In the case where (128 or less) bordered areas BRDAs are set midway, "OOh" is set as the start position information on the subsequent border out areas BRDOs. In this manner, it is possible to identify how many bordered areas BRDAs are set on the write-once information storage medium merely by checking to where the start position information on the border out areas BRDOs are recorded in the RMD field 3. In the embodiment shown in FIGS. 51 and 52, up to 128 expanded recording management zones RMZs can be set on one write-once information storage medium. As described above, there are two types of expanded recording management zones RMZs such as: 1) an expanded recording management zone RMZ set in the border-in area BRDI; and 2) an expanded recording management zone RMZ set by utilizing an R zone. In the embodiment shown in FIGS. 51 and 52, without discriminating these two types of RMZ zones, they are managed by receding a pair of the start position information on the expanded recording management zone RMZ (indicated by the physical sector number) and size information (number information on occupying physical sectors) in the RMD field 3. In the embodiment shown in FIGS. 51 and 52, although there has been recorded: information on a pair of the start position information (indicated by the physical sector number) and size information (number information on occupying physical sectors) on the expanded recording management zone RMZ, a set of the start position (indicated by the physical sector number) and the end position information (indicated by the physical sector number) on the expanded recording management zone RMZ may be recorded without being limited thereto. In the embodiment shown in FIGS. 51 and 52, although the expanded recording management zones RMZ numbers have been assigned in order set on the write-once type information storage medium, the expanded recording management data zone RMZ numbers can be assigned in order from the lowest physical sector number as a start position without being limited thereto. Then, the latest recording management data RMD is recorded, a currently used recording management zone (which is open to enable additional writing of RMD) is specified by the number of this expanded recording management zone RMZ. Therefore, the information recording/reproducing apparatus or the information reproducing apparatus identifies the start position information on the currently used (opened so that the RMZ can be additionally recorded) recording management zone based on these items of information, and carries out identification of which one is the latest recording management data RMD from the identified information. Even if the expanded recording management zone is arranged to be distributed onto the write-once type information storage medium, the information recording/reproducing apparatus or information reproducing apparatus can easily carry out identification of which one is the latest recording management data RMD by taking a data structure shown in FIGS. 51 and 52 each. Based on these items of information; the start position information on the currently used (opened) recording management zone is identified; and the location is accessed to identify to where the recording management data RMD has already been recorded. In this manner, the information recording/reproducing apparatus or the information reproducing apparatus can easily identify to where the updated latest recording management data may be recorded. In the case where 2) an expanded recording management zone RMZ set by utilizing an R zone has been set, one whole R zone corresponds to one expanded recording management zone RMZ. Thus, the physical sector number indicating the corresponding start position of the expanded recording management zone RMZ described in the RMD field 3 coincides with the corresponding physical sector number indicating the start position of the R zone described in the RMD fields 4 to 21. In the embodiment shown in FIGS. 51 and 52, up to 4606 (4351 + 255) R zones can be set in one write-once type information storage medium. This set R zone position information is recorded in the RMD field 4 to 21. The start position information on each R zone is displayed by the information on the physical sector number, and the physical sector numbers LRAs (Last Recorded Addresses) indicating the end recording position in each R zone are recorded in pair. Although the R zones described in the recording management data RMD are set in order of setting R zones in the embodiment shown in FIGS. 51 and 52, these zones can be set in order from the lowest physical sector number indicating the start position information without being limited thereto. In the case where R zone setting of the corresponding number is not provided, "OOh" is recorded in this field. Number information on invisible R zone is described in the RMD field 4. This number information on invisible R zone is indicated by a total number of the number of invisible R zones (zones in which area reserved for data recording is not made in data area DTA); the number of open type R zones (zones each having an unrecorded area in which additional writing can be carried out); and the number of complete type R zones (R zones which are already complete and which does not have an unrecorded area in which additional writing can be carried out). In the embodiment shown in FIGS. 51 and 52, it is possible to set up to two Open R zones in which additional writing can be carried out. In this way, by setting up to two Open R zones, it is possible to record video image information or audio information for which continuous recording or continuous reproduction must be guaranteed in one Open R zone, and then, separately record management information relevant to the video image information or audio information; general information used by a personal computer or the like; or file system management information in the remaining one Open R zone. Namely, it is possible to separately record plural items of information in another Open R zone according to type of user data to be recorded. This results in improved convenience in recording or reproducing AV information (video image information or audio information). In the embodiment shown in FIGS. 51 and 52, which R zone is an Open R zone is specified by the R zone allocation numbers arranged in the RMD fields 4 to 21. That is, the R zones are specified by the corresponding R zone number to the first and second Open R zones. A search can be easily made for the Open R zone by taking such a data structure. In the case where no Open R zone exists, "OOh" is recorded in that field. In the present embodiment, the end position of an R zone coincides with the end recording position in the Complete R zone, the end position of the R zone and the last recording position LRA in the R zone are different from each other in the Open T zone. On the way of additionally writing user information in the Open R zone (at a state that precedes completion of additional writing of the recording management data RMD to be updated), the end recording position and a recording position at which additional writing can be further carried out are shifted. However, after an additional writing process of user information has completed, after completing the additional writing process of the latest recording management data RMD to be recorded, the end recording position and an end recording position at which additional writing can be further carried out coincide with each other. Therefore, after completing the additional writing process of the latest recording management data RMD to be updated, in the case where additional writing of new user data is carried out, the control unit 143 in the information recording/reproducing apparatus shown in FIG. 11 carries out processing in accordance with procedures for: 1) checking a number of an R zone which corresponds to the Open R zone described in the RMD field 4; 2) checking a physical sector number indicating an end recording position in the Open R zone described in each of the RMD fields 4 to 21 to identify an end recording position at which additional writing can be carried out; and 3) starting additional writing from the above identified end recording position NWA at which additional writing can be carried out. In this manner, a new additional writing start position is identified by utilizing Open R zone information in the RMD field 4, thereby making it possible to sample a new additional writing start position simply and speedily. FIG. 53 shows a data structure in an RMD field in the embodiment shown in FIGS. 51 and 52. As compared with the embodiment shown in FIGS. 44 to 49, there are added: address information on a location in which recording condition adjustment has been made in the inner drive test zone DRTZ (which belongs to the data lead-in area DTLDI); and address information on a location in which recording condition adjustment has been made in the outer drive test zone DRTZ (which belongs to the data lead-out area DTLDO). These items of information are described in the physical segment block address numbers. Further, in the embodiment shown in FIG. 53, there are added: information relating to a method for automatically adjusting a recording condition (running OPC); and the end DSV (Digital Sum Value) value at the end of recording. FIG. 56 shows an outline of converting procedures for, after an ECC block is configured of a data frame structure in which user data in units of 2048 bytes has been recorded, and then, sync codes have been added, forming a physical sector structure to be recorded in an information storage medium. These converting procedures are employed in common for a read-only type information storage medium, a write-once type information storage medium, and a rewritable-type information storage medium. According to each converting stage, a data frame, a scrambled frame, a recording flame, or recorded data field are defined. The data frame is a location in which user data is recorded. This frame is composed of: main data consisting of 2048 types; a four-type data ID; a two-byte ID error detecting code (IED); a six-byte reserved bytes (RSV); and a four-byte error detecting code (EDC). First, after an IED (ID error detecting code) has been added to a data ID described later, the 6-byte reserved byte and main data consisting of 2048 bytes and in which the user data is recorded are added. Then, an error detecting code (EDC) is added. Then, scrambling relevant to the main data is executed. Here, a Cross Reed-Solomon Error Correction Code is applied to these scrambled 32 data frames (scrambled frames), and an ECC encode processing operation is executed. In this manner, a recording frame is configured. This recording frame includes a parity of outer-code (PO) and a parity of inner-code (PI). The PO and PI each are error correcting codes produced with respect ECC blocks, each of which is formed of 32 scrambled frames. The recording frame, as described previously, is subjected to ETM (Eight to Twelve Modulation) for converting eight data bits to 12- channel bits. Then, a sync code SYNC is added to the beginning on a 91 by 91 bytes basis, and 32 physical sectors are formed. As described in the lower right frame shown in FIG. 56, the present embodiment is featured in that one error correcting unit (ECC block) is composed of 32 sectors. As described later, the numbers "0" to 31" in each frame shown in FIG. 60 or 61 indicate the numbers of physical sectors, respectively, and a structure is provided to ensure that one large ECC block is composed of a total of 32 physical sectors. In a next-generation DVD, even in the case where a scratch whose extent is identical to that of a current-generation DVD adheres to an information storage medium surface, it is required to enable reproduction of precise information by an error correction processing operation. In the present embodiment, recording density has been improved for the achievement of high capacity. As a result, in the case where a conventional one ECC block = 16 sectors, a length of a physical scratch which can be corrected by error correction is reduced as compared with a conventional DVD. As in the present embodiment, there is attained advantageous effect that one ECC block is composed of 32 sectors, thereby making it possible to increase an allowable length of a scratch on the information storage medium surface for which error correction can be carried out and to ensure compatibility/format continuity of a current DVD ECC block structure. FIG. 57 shows a structure in a data frame. One data frame is 2064 bytes consisting of 172 bytes x 2 x 6 rows, and includes main data of 2048 bytes. IED is an acronym for IE Error Detection Code, and denotes a reserved area for enabling setting of information in the future. EDC is an acronym for Error Detection Code, and denotes an additional code for error detection of a whole data frame. FIG. 50 shows a data structure in a data ID shown in FIG. 57. The data ID is composed of items of information on data frames 921 and 922. The data frame number indicates a physical sector number 922 of the corresponding data frame. The data frame information 921 is composed of the following items of information. - Format type 931 ... Ob: This indicates CLV Ib: This indicates zone configuration - Tracking method 932 ... Ob: This is pit-compatible and uses a DPD (Differential Phase Detect) technique in the present embodiment Ib: This is pre-groove compatible and uses a push-pull technique or a DPP (Differential Push- Pull) technique. - Recording film reflection factor 933 ... Ob: 40% or more Ib: 40% or less - Recording type information 934 ... Ob: General data Ib: Real time data (Audio Video data) - Area type information 935 ... OOb: Data area DTA Olb: System lead-in area SYLDI or data lead-in area DTLDI lOb: Data lead-out area DTLDO or system lead-out area SYLDO - Data type information 936 ... Ob: Read-only data Ib: Rewritable data - Layer number 937 ... Ob: Layer 0 Ib: Layer 1 FIG. 58A shows an example of default values assigned to a feedback shift register when a frame after scrambled is produced. FIG. 58B shows a circuit configuration of the feedback shift register for producing scrambled bytes. The values of r7 (MSB) to rO (LSB) are used as scramble bytes while they are shifted by 8 by 8 bit basis. As shown in FIG. 58A, 16 types of preset values are provided in the present embodiment. The default preset numbers shown in FIG. 58A are equal to 4 bits of data ID (b7 (MSB) to b4 (LSB)). When data frame scrambling is started, the default values of r!4 to rO must be set to the default preset values in a table shown in FIG. 58A. The same default preset value is used for 16 continuous data frames. Next, the default preset values are changed, and the changed same preset value is used for the 16 continuous data frames. The least significant eight bits of the default values of r7 to rO are sampled as a scramble byte SO. Then, eight-bit shifting is carried out, and the scrambled byte is then sampled. Such an operation is repeated 2047 times. FIG. 59 shows an ECC block structure in the present embodiment. The ECC block is formed of 32 scrambled frames. 192 rows + 16 rows are arranged in a vertical direction, and (172 + 10) x 2 columns are arranged in a horizontal direction. BQ,Q, B]_,Q, ... are one byte, respectively. PO and PI are error correction codes, and an outer parity and an inner parity. In the present embodiment, an ECC block structure using a multiple code is configured. That is, as error correction additional bits, a structure is provided such that, PI (Parity in) is added in a "row" direction, and PO (Parity out) is added in a "column" direction. A high error correction capability using an erasure correction and a vertical and horizontal repetitive correction process can be guaranteed by configuring such an ECC block structure using a multiple code. Unlike a conventional DVD ECC block structure, the ECC block structure shown in FIG. 59 is featured in that two Pis are set in the same "row". That is, PI of 10-byte size described at the center in FIG. 59 is added to 172 bytes arranged at the left side. That is, for example, 10-byte PI from BQ o to BO 172 is added to 172-byte data from BQ g to BQ 171/ and 10-byte PI from 61,172 to Bl 181 i-s added to 172-byte data from B]_ Q to Bl,171- The PI of 10-byte size described at the right end of FIG. 59 is added to 172 bytes arranged at the center on the left side of the figure 59. That is, for example, 10-byte PI from Eg 354 to BQ 363 are added to 172-byte data from &QriQ2 to B0,353- FIG. 60 shows an illustration of a frame arrangement after scrambled. Units of (6 rows x 172 bytes) are handled as one frame after scrambled. That is, one ECC block is formed of 32 frames after scrambled. Further, this system handles a pair of (block 182 bytes x 207 bytes). When L is assigned to the number of each frame after scrambled, in the left side ECC block, and R is assigned to the number of each frame after scrambled in the right side ECC block, the frames after scrambled are arranged as shown in FIG. 60. That is, the left and right frames after scrambled exist alternately at the left side block, and the frames after scrambled exist alternately at the right side block. That is, the ECC block is formed of 32 frames after continuously scrambled. Lines of the left half of odd numbered sectors each are exchanged with those of the right half. 172 x 2 bytes x 192 rows are equal to 172 bytes x 12 rows x 32 scrambled frames, and are obtained as a data area. 16-byte PO is added to form an outer code of RS (208, 192, 17) in each 172 x 2 columns. 10-byte PI (RS (182, 172, 11)) is added to each 208 x 2 rows in the left and right blocks. PI is added to a row of PO as well. The numerals in frames indicate scrambled frame numbers, and suffixes R and L denote the right half and the left half of the scrambled frame. The present embodiment is featured in that the same data frame is arranged to be distributed in a plurality of small ECC blocks. Specifically, in the present embodiment, a large one ECC block is composed of two small ECC blocks, and the same data frame are arranged to be alternately distributed into two small ECC blocks. As has already been described in FIG. 59, PI of 10-byte size described at the center is added to 172 bytes arranged at the left side, and PI of 10 byte size described on the right end is added to 172 bytes arranged at the center on the left side. Namely, the left side small ECC block is composed of continuous PI of 10 bytes from the left end of FIG. 59, and the right side small ECC block is composed of 10 bytes at the right end from the central 172 bytes. The signs in each frame are set in response to these blocks in FIG. 60. For example, "2-R" denotes which of a data frame number and the left and right small ECC blocks one belongs to (for example, one belongs to right side small ECC block in second data frame). As described later, with respect to each of the finally configured physical sectors, the data contained in the same physical sector is also alternately arranged to be distributed into the left and right small ECC blocks (the columns of the left half in FIG. 61 are included in the left side small ECC block (small ECC block "A" on the left side shown in FIG. 64), and the column of the right half are included in small ECC blocks (small ECC block B on the right side shown in FIG. 64). Thus, when the same data frame is arranged to be distributed in a plurality of small ECC blocks, the reliability of recording data is improved by improving an error correction capability of the data contained in a physical sector (FIG. 61). For example, let us consider a case in which a track fails at the time of recording; the recorded data is overwritten; and data for one physical sector is damaged. In the present embodiment, the damaged data contained in one sector is subjected to error correction by using two small ECC blocks; a burden on error correction in one ECC block is reduced; and error correction with better performance is guaranteed. In the present embodiment, even after forming an ECC block, a structure is provided such that a data ID is arranged at the start position of each sector, thus making it possible to check a data position at the time of access at a high speed. FIG. 61 shows an illustration of a PO interleaving method. As shown in FIG. 61, 16 parities are distributed on one by one row basis. That is, 16 parity rows are arranged on a one by one row basis with respect to two recording frames placed. Therefore, a recording fame consisting of 12 rows is obtained as 12 rows + 1 row. After this row interleaving has been carried out, 13 rows x 182 bytes are referred to as a recording frame. Therefore, an ECC block after row interleaved is formed of 32 recording frames. In one recording, as described in FIG. 60, 6 rows exist in each of the right side and left side blocks. POs are arranged so as to be positioned in different rows between a left block (182 x 208 bytes) and a right block (182 x 208 bytes). FIG. 61 shows one complete type ECC block. However, at the time of actual data reproduction, such ECC blocks continuously arrive at an error correction processing section. In order to improve such an error correction processing capability, there is employed an interleaving system as shown in FIG. 61. Referring to FIG. 61, a detailed description will be given with respect to a relationship from a structure in one data frame shown in FIG. 57 to a PO interleaving method shown in FIG. 61. FIG. 64 is an enlarged view showing, an upper side portion of an EC block structure after PO-interleaved shown in FIG. 61, wherein allocation locations of data ID, IED, RSV, and EDC shown in FIG. 57 are explicitly indicated, thereby visually identifying a series of conversion from FIGS. 57 to 61. "0-L" "0-R", "1-R", and "1-L" shown in FIG. 64 correspond to "0-L", "0-R", "1-R", and "1-L" shown in FIG. 60, respectively. The "0-L" and "1-L" denote data obtained after only the main data has been scrambled with respect to the left half shown in FIG. 57, that is, a set composed of 172 bytes and six rows from the center line to the left side. Similarly, the "0-R" and "1-R" denote data obtained after only the main data has been scrambled with respect to the right half shown in FIG. 57, that is, a set composed of 172 bytes and six rows from the center line to the right side. Therefore, as is evident from FIG. 57, data ID, IED, and RSV are arranged in order from the beginning of the first row (row 0) to byte 12 of "0-L" and "1-L". In FIG. 64, the centerline to the left side configures the left side small ECC block "A", and the centerline to the right side configures the right side small ECC block "B". Therefore, as is evident from FIG. 64, data ID#1, data ID#2, IED#0, IED#2, RSV#0, and RSV#2 included in "0-L" and "2-L" are included in the left side small ECC block "A". In FIG. 60, "0-L" and "2-L" are arranged at the left side, and "0-R" and "2-E" are arranged at the right side. In contrast, "1-R" and "1-L" are arranged at the left and right sides, respectively. Data ID#1, IED#1, and RSV#1 are arranged from the beginning to byte 12 of the first row in "1-L". Thus, as a result of reversing the left and right allocations, as is evident from FIG. 64, data ID#1, IED#1, and RSV#1 included in "1-L" is configured in the right side small ECC block "B". In the present embodiment, a combination of "0-L" and "0-R" in FIG. 64 is referred to as a "0-th recording frame" and a combination of "1-L" and "1-R" is referred to as a "first recording frame". The boundary between the recording frames are indicated by the bold characters shown in FIG. 64. As is evident from FIG. 64, data ID is arranged at the beginning of each recording frame and PO and PI-L are arranged at the end of each recording frame. As shown in FIG. 64, the present embodiment is featured in that small ECC blocks in which data ID is included are different from each other depending on the odd-numbered and even-numbered recording frames, and data ID, IED, and RSV are alternately arranged in the left side and right side small ECC blocks "A" and "B" in accordance with continuous recording frames. The error correction capability in one small ECC lock is limited, and error correction is disabled with respect to a random error exceeding a specific number or a burst error exceeding a specific length. As described above, data ID, IED, and RSV are alternately arranged in the left side and right side small ECC blocks "A" and "B", thereby making it possible to improve the reliability of reproduction of data ID. That is, even if a defect on an information storage medium frequently occurs, disabling error correction of any of the small ECC blocks and disabling decoding of data ID to which the faulty block belongs, data ID, IED, and RSV are alternately arranged in the left side and right side small ECC blocks "A" and "B", thus enabling error correction in the other small ECC block and enabling decoding the remaining data ID. Because the address information contained in data ID continuously lasts, the information on data ID is used, enabling interpolation with respect to the information on data ID which has not been successfully decoded. As a result, the access reliability can be improved according to the embodiment shown in FIG. 64. The numbers parenthesized at the left side of FIG. 64 denote row numbers in an ECC block after POinterleaved. In the case where numbers are recorded in an information storage medium, row numbers are sequentially recorded from the left to the right. In FIG. 64, data ID intervals included in each recording frame are always constantly arranged, and thus, there is attained advantageous effect that data ID position searching capability is improved. A physical sector structure is shown in FIGS. 62A and 62B. FIG. 62A shows an even numbered physical sector structure, and FIG. 62B show an odd numbered data structure. In FIGS. 62A and 62B, with respect to both of an even recorded data field and an odd recorded data field, outer parity PO information shown in FIG. 61 is inserted into a sync data area contained in the last 2 sync frames (i.e., in a portion at which the last sync code is SYS and a portion at which the immediately succeeding sync data and sync code is SY1; and a portion at which sync code is SYl and a portion at which the immediately succeeding sync data is arranged in the sync data area shown in FIG. 61 wherein information of outer parity PO is inserted). Part of the left side PO shown in FIG. 60 is inserted at the last two sync frames in the even recorded data field, and part of the right side PO shown in FIG. 60 is inserted at the last two sync frames in the odd recorded data field. As shown in FIG. 60, one ECC block is composed of the left and right small ECC blocks, respectively, and the data on PO groups alternately different depending on sectors (the data on PO belonging to left small ECC block or the data on PO belonging to right small ECC block) is inserted. The even numbered physical sector structure shown in FIG. 62A and the odd numbered data structure shown in FIG. 62B are divided into two sections at a center line. The left side "24 + 1092 + 24 + 1092 channel bits are included in the left side small ECC block shown in FIG. 59 or 60, and the right side "24 + 1092 + 24 + 1092 channel bits are included in the right side small ECC block shown in FIG. 59 or 60. In the case where the physical sector structure shown in FIGS. 62A and 62B is recorded in an information storage medium, this structure is serially recorded on one by one column base. Therefore, for example, in the case where channel bit data on an even numbered physical sector structure shown in FIG. 62A is recorded in an information storage medium, the data on 2232 channel bits first recorded is included in the left side small ECC block, and the data on the 2232 channel bits recorded next is included in the right side small EC block. Further, the data on 2232 channel bits recorded next is included in the left side small ECC block. In contrast, in the case where the channel bit data on an odd numbered data structure shown in FIG. 62B is recorded in an information storage medium, the data on 2232 channel bits first recorded is included in the right side small ECC block, and the data on the 2232 channel bits recorded next is included in the left side small EC block. Further, the data on 2232 channel bits recorded next is included in the right side small ECC block. Thus, the present embodiment is featured in that the same physical sector is alternately included in two small ECC blocks on a 2232 by 2322 channel bit basis. In other words, a physical sector is formed in the shape such that the data included in the right side small ECC block and included in the left side small ECC block are alternately arranged to be distributed on a 2232 by 2332 channel bit basis, and the formed physical sector is recorded in an information storage medium. As a result, there is attained advantageous effect that a structure strong to a burst error can be provided. For example, let us consider a state in which a lengthwise scratch occurs in a circumferential direction of an information storage medium, and there occurs a burst error which disables decoding of data exceeding 172 bytes. In this case, a burst error exceeding 172 bytes is arranged to be distributed in two small ECC blocks. Thus, a burden on error correction in one ECC block is reduced, and error correction with better performance is guaranteed. The present embodiment is featured by, as shown in FIGS. 62A and 62B, a data structure in a physical sector is different from another depending on whether or not the physical sector number of a physical sector configuring one ECC block is an even number or an odd number. Namely, 1) Small ECC blocks (right side or left side) to which the first 2232 channel bit data of a physical sector belongs are different from each other; and 2) There is provided a structure in which data on a PO group alternately different from each other depending on sectors is inserted. As a result, in order to guarantee a structure in which data ID is arranged at the start position of all the physical sectors even after an ECC block has been configured, a data position check at the time of access can be made at a high speed. In addition, POs which belong to different small ECC blocks are mixed and inserted into the same physical sector, structurally simplifying a method employing a PO inserting method as shown in FIG. 61, facilitating information sampling on a sector by sector manner after error correction processing in an information reproducing apparatus; and simplifying an ECC block data assembling process in an information recording/reproducing apparatus. In a method for specifically achieving the above contents, PO interleaving and inserting positions have different structures depending on the left and right. Portions indicated by the narrow double lines shown in FIG. 61 or portions indicated by the narrow double line and shading indicate the PO interleaving and inserting positions. PO is inserted at the left end in an even numbered physical sector number or at the right end in an odd numbered physical sector number. By employing this structure, even after an ECC block has configured, data ID is arranged at the start position of a physical sector, thus making it possible to check a data position at the time of access at high speed. FIG. 63 shows an embodiment of specific pattern contents from sync codes "SYO" to "SYS" shown in FIGS. 62A and 62B. Three states from State 0 to State 2 are provided in accordance with a modulation rule according to the present embodiment (a detailed description will be given later). Four sync codes from SYO to SYS are set, and each code is selected from the left and right groups shown in FIG. 63 according to each state. In a current DVD specification, as a modulation system, there employed RLL(2, 10) of 8/16 modulation (8 bits are converted to 16 channel bits (a minimum value is 2 and a maximum value is 10 when Run Length Limit: d = 2, k = 10: "0" continuously lasts), four states from State 1 to State 4, i.e., eight types of sync codes from SYO to SY7 are set. In comparison, in the present embodiment, types of sync codes are decreased. In an information recording/reproducing apparatus or an information reproducing apparatus, at the time of information reproduction from an information storage medium, types of sync code is identified in accordance with a pattern matching technique. As in the present embodiment, by significantly decreasing types of sync codes, target patterns required for matching are decreased in number; a processing operation required for pattern matching is simplified; and the processing efficiency is improved, making it possible to improve a recognition speed. In FIG. 63, a bit (channel bit) indicated by "#" denotes a DSV (Digital Sum Value) control bit. As described later, the above DSV control bit is determined so as to suppress a DC component by means of a DSV controller (so as to make a value of DSM close to 0). The present embodiment is also featured in that a polarity inversion channel bit "#" is included in a sync code. There is attained advantageous effect that a value of "#" can be selected as "1" or "0" so that the DSV value is close to "0" in a macroscopic point of view, including both frame data fields (1092 channel bit fields shown in FIGS. 62A and 62B) sandwiching the above sync code, enabling DSV control from the macroscopic point of view. As shown in FIG. 63, the sync codes in the present embodiment is composed of the sections below. 1) Sync position detecting code section This section has a common pattern in all sync codes, and forms a fixed code area. A sync code allocation position can be detected by detecting this code. Specifically, this section denotes the last 18 channel bits "010000 000000 001001" in each sync code in FIG. 63. 2) Modulation conversion table selector code section This section forms part of a variable code area, and changes in response to state number at the time of modulation. The first channel bit shown in FIG. 63 corresponds to this section. That is, in the case where one of State 1 and State 2 is selected, the first channel bit is set to "1" in any of the codes from SYO to SYY3. When State 0 is selected, the first channel bit of a sync code is set to "1". However, as an exception, the first channel bit of SY3 in State 0 is set to "0". 3) Sync frame position identification code section Part of a variable code area is composed of codes identifying types from SYO to SY3 in sync codes. The first to sixth channel bit section in each sync code shown in FIG. 63 corresponds to this section. As described later, a relative position in the same sector can be detected from a connection pattern of three by three sync codes continuously detected. 4) DC suppressing polarity inversion code section A channel bit at a position "#" shown in FIG. 63 corresponds to this section. As described above, this bit is inverted or non-inverted, thereby making close to "0" the DSV value of a channel bit pattern including the preceding and succeeding frame data. In the present embodiment, 8/12 modulation (ETM: Eight to Twelve Modulation), RLL (1, 10) is employed as a modulation method. That is, eight bits are converted to 12-cahnnel bits at the time of modulation, and a minimum value (d value) is set to 1, and a maximum value (k value) is set to 10 in a range such that the settings "0" after converted are continuous. In the present embodiment, although high density can be achieved more significantly than conventionally by setting d = 1, it is difficult to obtain a sufficiently large reproduction signal amplitude at a site indicated by the mark indicating the highest density. Therefore, as shown in FIG. 11, an information recording/reproducing apparatus according to the present embodiment has the PR equalizing circuit 130 and the Viterbi decoder 156, and enables very stable signal reproduction by using a PRML (Partial Response Maximum Likelihood) technique. In addition, k = 10 is set, and thus, there is no case in which eleven or more "0" settings are continuous in the modulated general channel bit data. By utilizing this modulation rule, the above sync position detecting code section has a pattern which hardly appears in the modulated general channel bit data. That is, as shown in FIG. 63, in the sync position detecting code section, 12 (= k + 2) "0"s are continuously arranged. The information recording/reproducing apparatus or the information reproducing apparatus finds this section and detects a position of the sync position detecting code section. In addition, if "0" continuously lasts too much, a bit shift error is likely to occur. Thus, in order to reduce this problem, in the sync position detecting code section, a pattern having less continuous "0"s is arranged immediately after that portion. In the present embodiment, d = 1, and thus, it is possible to set "101" as the corresponding pattern. However, as described above, a sufficiently large reproduction signal amplitude is hardly obtained at a site of "101" (at a site indicating the highest density), and thus, "1001" is arranged instead, obtaining a pattern of the sync position detecting code section as shown in FIG. 63. The present embodiment is featured in that, as shown in FIG. 63, 18 channel bits at the back side in a sync code are independently used as (1) sync position detecting code section, and the front side 6 channel bits are used as (2) modulation conversion table selector code section; (3) sync frame position identification code section; or (4) DC suppression polarity inversion code section. There is attained advantageous effect that in the sync codes, the sync position detecting code section in item (1) is provided independently, thereby facilitating single detection and enhancing sync position detecting precision; the code sections in items (2) to (4) are used in common in the 6-channel bits, thereby reducing the data size of the whole sync codes (channel bit size); and a sync data occupying rate is increased, thereby improving substantial data efficiency. The present embodiment is featured in that, from among four types of sync codes shown in FIG. 63, only SYO is arranged at the first sync frame position in a sector, as shown in FIGS. 62A and 62B. Advantageous effect thereof includes that the start position in a sector can be identified immediately merely by detecting SYO, and the start position sampling process in the sector is extremely simplified. The present embodiment is also featured in that all of the combination patterns of three continuous sync codes are different from each other in the same sector. A detailed description will be given with respect to the pattern contents of a reference code recorded in the reference code recording zone RCZ shown in FIGS. 35A to 35C. In a current DVD, an "8/16 modulation" system for converting 8-bit data to 16- channel bits is employed as a modulation system. As a pattern of a reference code serving as a channel bit pattern recorded in an information storage medium after modulated, there is employed a repetition pattern "00100000100000010010000010000001". In comparison with this pattern, in the present embodiment, ETM modulation for modulating 8-bit data into 12-channel bits is used as shown in FIGS. 32 to 34, providing an RLL (1, 10) 5 run length restriction. In addition, the PRML technique is employed for signal reproduction from the data lead-in area DTLDI, data area DTA, data lead-out area DTLDO, and middle area MDA. Therefore, there is a need for setting the above described modulation rule 10 and a pattern of a reference code optimal for PRML detection. In accordance with the RLL(1, 10) run length restriction, a minimum value of continuous "0" settings is "d = 1", and is a repetition pattern of "10101010". Assuming that a distance from a code "0" 15 to the next adjacent code is "T", a distance relevant to the adjacent "1" in the above pattern is obtained as "2T". In the present embodiment, in order to achieve high density of an information storage medium, as described previously, a reproduction signal from the 20 repetition pattern ("10101010") of "2T" recorded on the information storage medium is close to a shutdown frequency of MTF (Modulation Transfer Function) characteristics of an objective lens in an optical head (exists in the information recording/reproducing unit 25 141 shown in FIG. 11); and thus, a degree of modulation (signal amplitude) is hardly obtained. Therefore, in the case where a reproduction signal from a repetition pattern ("10101010") of "2T" has been used as a reproduction signal used for circuit tuning of the information reproducing apparatus or the information recording/reproducing apparatus (for example, 5 initialing and optimizing tap coefficients in the tap controller 332 shown in FIG. 15), noise effect is significant, and stabilization is poor. Therefore, with respect to a signal after modulated in accordance with RLL(1, 10) run length restriction, then, it is 10 desirable to carry out circuit tuning by using a pattern of "3T" having high density. In the case where a digital sum value (DSV) of the reproduction signal is considered, an absolute value of a DC (direct current) value increases in proportion to the number of 15 continuous "0"s between "1" and next "1" that immediately follows it, and the increased value is added to the immediately preceding DSV value. The polarity of this added DC value is inverted every time "1" is reached. Therefore, as a method for setting the 20 DSV value to "0" where a channel bit pattern having continuous reference code is followed, the DSV value is set to be "0" in 12 channel bit patterns after ETMmodulated, whereby the degree of freedom in reference code pattern design is increased more significantly by 25 setting to an odd number the number of generated "1" appearing in 12 channel bit patterns after ETMmodulated; offsetting a DC component generated in one set of reference code cells consisting of a next set. Therefore, in the present embodiment, the number of "1" appearing in the reference code cells consisting of 12 channel bit patterns after ETM-modulated is set to 5 an odd number. In the present embodiment, in order to achieve high density, there is employed a mark edge recording technique in which a location of "1" coincides with a boundary position of a recording mark or an emboss pit. For example, in the case where a 10 repetition pattern of "3T" ("100100100100100100100") is followed, there occurs a case in which a length of a recording mark or an emboss pit and a length of a space between the mark and pit are slightly different from each other depending on a recording condition or an 15 original master producing condition. In the case where the PRML detecting technique has been employed, a level value of a reproduction signal becomes very important. As described previously, even in the case where the length of the recording mark or emboss pit and the 20 length of the space between the mark and pit are different from each other, there occurs a necessity of correcting such slightly different component in a circuit manner so as to enable signal detection stably and precisely. Therefore, a reference code for tuning 25 a circuit constant has a space with a length of "3T", like a recording mark or an emboss pit with a length of "3T", thereby improving the precision of tuning a circuit constant. Thus, if a pattern of "1001001" is included as a reference code pattern according to the present embodiment, the recording mark or emboss pit having the length "3T"; and a space are always 5 arranged. In addition, circuit tuning also requires a pattern in a non-dense state as well as a pattern ("1001001") having a high density. Therefore, in consideration of that fact that a non-dense state (pattern in which "0" is continuously and frequently 10 generated) is generated at a portion at which a pattern of "1001001" has been excluded from among 12 channel bit patterns after ETM-modulated and the number of generated "l"s is set in an odd number, with respect to a reference code pattern, a repetition of 15 "100100100000" is obtained as an optical condition, as shown in FIG. 72. In order to ensure that the channel bit pattern after modulated is produced as the pattern, although not shown, there is a need for setting to "A4h" a data word before modulated, when utilizing a 20 modulation table specified in an H format. This data on "A4h" (hexadecimal notation) corresponds to a data symbol "164" (decimal notation). A description will be given below with respect to how to produce specific data in accordance with the 25 above data conversion rule. First, data symbol "164" (= "OA4h") is set to main data "DO to D2047" in the data frame structure described previously. Next, a data frame 1 to a data frame 15 are pre-scrambled in advance by an initial preset number "OEh", and a data frame 16 to a data frame 31 are pre-scrambled in advance by an initial preset number "OFh". If pre- 5 scrambling is applied in advance, when scrambling is applied in the data conversion rule described previously, scrambling is applied in duplicate, and a data symbol "164" (= "OA4h") appears as it is (when scrambling is applied in duplicate, an original pattern 10 is returned). When pre-scrambling is applied to all of the reference codes, each of which is formed of 32 physical sectors, DSV control cannot be made, and thus, pre-scrambling cannot be applied to only data frame 0 in advance. After the foregoing scrambling has been 15 applied, if modulation is carried out, a pattern shown in FIG. 72 is recorded on the information storage medium. Referring to FIG. 73, a description will be given with respect to a comparison in data recording format 20 between a variety of information storage mediums in the present embodiment. FIG. 73 (a) shows a data recording format in a conventional read-only type information storage medium DVD-ROM; a conventional write-once type information storage medium DVD-R; and a conventional 25 DVD-RW; FIG. 73 (b) shows a data recording format in a read-only type information storage medium in the present embodiment; FIG. 73 (c) shows a data recording format of a write-once type information storage medium in the present embodiment; and FIG. 73 (d) shows a data recording format of a rewritable-type information storage medium. For the sake of comparison, ECC blocks 5 411 to 418 are shown as the same size. However, one ECC block is composed of 16 physical sectors in the conventional read-only type information storage medium DVD-ROM shown in FIG. 73 (a); the conventional writeonce type information storage medium DVD-R; and the 10 conventional rewritable type information storage medium DVD-RW, whereas, in the present embodiment shown in FIGS. 73 (b) to 73 (d) , one ECC block is composed of 32 physical sectors. The present embodiment is featured in that guard areas 442 to 448 having the same length 15 as a sync frame length 433 is provided between ECC blocks #1 411 to #8 418, as shown in FIGS. 73 (b) to 73 (d). In the conventional read-only type information storage medium DVD-ROM, ECC blocks #1 411 to #8 418 are continuously recorded as shown in FIG. 73 (a). If an 20 attempt is made to allocate compatibility in data recording format with the conventional read-only type information storage medium DVD-ROM by means of the conventional write-once type information storage medium DVD-R or the conventional rewritable type information 25 storage medium DVD-RW, if an additional writing or rewriting process called restricted overwrite is carried out, there has been a problem that part of the ECC block is damaged due to overwriting and the data reliability at the time of reproduction is significantly degraded. In contrast, as in the present embodiment, if guard areas 442 to 448 are arranged 5 between data fields (ECC blocks), there is attained advantageous effect that an overwrite location is restricted to the guard areas 442 to 448, and the data damage in a data field (ECC block) can be prevented. The present embodiment is secondarily featured in that 10 the lengths of the above guard areas 442 to 448 are adjusted to conform with a sync frame length 433 which is one sync frame size, as shown in FIGS. 73 (a) to 73 (d). As shown in FIGS. 62A and 62B, sync codes are arranged in space in determined sync frame lengths 433 15 having 1116 channel bits, and a sync code position is sampled by utilizing this predetermined cyclic space in the sync code position detector unit 145 shown in FIG. 11. In the present embodiment, there is attained advantageous effect that, even if the guard areas 442 20 to 448 are encompassed at the time of reproduction by making adjustment to conform with the length sync frame length 433 of the guard areas 442 to 448, the sync frame space is kept unchanged, thus facilitating sync code position detection at the time of reproduction. 25 Further, in the present embodiment, sync data is arranged in the guard area for the purpose of: 1) improving detection precision of the sync code position detection while matching a generation frequency of the sync codes even in a location encompassing the guard areas 442 to 448; and 2) facilitating judgment of a position in a 5 physical sector including the guard areas 442 to 448. Specifically, as shown in FIG. 75, a postamble field 481 is formed at the start position of each of the guard areas 442 to 468, and a sync code "SY1" of sync code number "1" shown in FIG. 63 is arranged in 10 that postamble area 481. As is evident from FIGS. 62A and 62B, combinations of sync code numbers of three continuous sync codes in a physical sector are different from each other in all locations. Further, combinations of sync code numbers of three continuous 15 sync codes considering up to sync code numbers "1" in the guard areas 442 to 448 are also different from each other in all locations. Therefore, the judgment of a position in physical sectors including a location of the guard area as well as positional information in the 20 physical sectors can be made in accordance with sync code number combinations of three continuous sync codes in an arbitrary area. FIG. 75 shows a detailed structure in the guard areas 441 to 448 shown in FIG. 73. The present 25 embodiment is featured in that, although a structure in physical sectors is composed of a combination of the sync code 431 and sync data 432, the guard areas 441 to 448 is composed of a combination of a sync code 433 and sync data 434 similarly; and, in an area of the sync data 434 contained in the guard area #3 443, data is arranged, the data being modulated in accordance with 5 the same modulation rule as the sync data 432 in sectors. An area in one ECC block #2 412 composed of 32 physical sectors shown in FIG. 59 is referred to as a data field 470 in the invention. VFO (Variable Frequency Oscillator) areas 471 and 10 472 in FIG. 75 are utilized for synchronization of a reference clock of an information reproducing apparatus or an information recording/reproducing apparatus when the data field 470 is reproduced. As the contents of data recorded in the areas 471 and 472, the data before 15 modulated, in a common modulation rule described later, is obtained as a continuous repetition of "7Eh", and a channel bit pattern actually described after modulated is obtained as a repetition of "010001 000100" (pattern in which three "0" settings are repeated). In order to 20 obtain this pattern, it is necessary to set the start bytes of the VFO areas 471 and 472 to State 2. The pre-sync areas 477 and 478 indicates a boundary position between the VFO areas 471 and 472 and the data area 470, and a recording channel bit pattern 25 after modulated is a repetition of "100000 100000" (pattern in which continuous five "0" settings are repeated). The information reproducing apparatus or the information recording reproducing apparatus detects a pattern change position of a repetition pattern of "100000 100000" in pre-sync areas 477 and 478 and recognizes that the data area 470 approaches, from a 5 repetition pattern of "010001 000100" contained in the VFO areas 471 and 472. A postamble area 481 indicates an end position of the data area 470 and designates a start position of the guard area 443. A pattern in the postamble area 10 481 coincides with a pattern of "SY1" in a SYNC code shown in FIG. 63, as described above. An extra area 482 is an area used for copy control or illegal copy protection. In particular, in the case where this area is not used for copy control or illegal 15 copy protection, all "Os" are set by channel bits. In a buffer area, data before modulated, which is identical to that in the VFO areas 471 and 472, is obtained as a continuous repetition of "7Eh", and the actually recorded channel bit pattern after modulated 20 is obtained as a repetition pattern of "010001 000100" (pattern in which continuous three 0 settings are repeated). In order to obtain this pattern, it is necessary to set the start bytes of the VFO areas 471 and 472 to State 2. 25 As shown in FIG. 75, a postamble area 481 in which a pattern of "SYl" is recorded corresponds to the sync code area 433; and an area from the immediately succeeding extra area 482 to a pre-sync area 478 corresponds to the sync data area 434. An area from the VFO area 471 to the buffer area 475 (namely, area including the data area 470 and part of the preceding 5 and succeeding guard areas) is referred to as a data segment 490 in the invention. This area indicates the conditions different from those of a "physical segment" described later. The data size of each item of data shown in FIG. 75 is expressed by byte number of data 10 before modulated. In the present embodiment, without being limited to a structure shown in FIG. 75, the following method can be employed as another embodiment. That is, the pre-sync area 477 is arranged midway of the VOF areas 15 471 and 472 shown in FIG. 75 instead of allocating the pre-sync area 477 at the boundary section between the VOF area 471 and the data area 470. In such another embodiment, a distance correlation is taken by spacing a distance between a sync code "SYO" and the pre-sync 20 area 477 arranged at the start position of the data block 470; the pre-sync area 477 is set as pseudo-Sync; and the pre-sync area 477 is set as distance correlation information on a real Sync position (although it is different from a distance relevant to 25 another Sync position). If a real Sync position cannot be detected, Sync is inserted into a position at which the real position generated from a pseudo Sync position would be detected. Another embodiment is featured in that the pre-sync area 477 is thus spaced slightly from real Sync ("SYO"). When the pre-sync area 477 is arranged at the beginning of the VFO areas 471 and 472, 5 the role of the pre-sync becomes weaken because PLL of a read clock is not locked. Therefore, it is desirable that the pre-sync area 477 be arranged at the intermediate position of the VFO areas 471 and 472. In the invention, address information in a 10 recording type (rewritable-type or write-once) information storage medium is recorded in advance by using wobble modulation. The present embodiment is featured in that phase modulation of ±90 degrees (180 degrees) is used as a wobble modulation system, 15 and NRZ (Non Return to Zero) method is employed, recording address information in advance with respect to an information storage medium. A specific description will be given with reference to FIG. 76. In the present embodiment, with respect to address 20 information, the 1-address bit (referred to as an address symbol) area 511 is expressed by a four-wobble cycle, and a frequency and an amplitude/a phase are matched everywhere in the 1-address bit area 511. In the case where the same values of address bits are 25 continued, the same phase continuously lasts at the boundary section of the 1-address bit areas 511 (at a portion indicated by "triangular mark" shown in FIG. 76). In the case where an address bit is inverted, wobble pattern inversion (180-degree shift of phase) occurs. In the wobble signal detector unit 135 of the information recording/reproducing apparatus 5 shown in FIG. 11, a boundary position of the above address bit area 511 (location indicated by "triangular mark" shown in FIG. 76) and a slot position 412 which is a boundary position of a 1-wobble cycle are detected at the same time. Although not shown in the wobble 10 signal detector unit 135, a PLL (Phase Lock Loop) circuit is incorporated, and PLL is applied in synchronism with both of the boundary position of the above address bit area 511 and the slot position 412. If the boundary position of this address bit area 511 15 or the slot position 412 is shifted, the wobble signal detector unit 135 is out of synchronization, disabling precise wobble signal reproduction (reading). A gap between the adjacent slot positions 412 is referred to as a slot gap 513. As this slot gap 513 is physically 20 closer, synchronization with a PLL circuit can be easily obtained, enabling stable wobble signal reproduction (reading of contained information). As is evident from FIG. 76, this slot gap 513 coincides with a 1-wobble cycle. As a wobble modulating method, 25 although an AM (Amplitude Modulation) system for changing a wobble amplitude is easily affected by dust or scratch adhering to the information storage medium surface, the above phase modulation is hardly comparatively affected by dust or scratch adhering to the information storage medium surface because a change of a phase is detected instead of a signal amplitude in 5 the above phase modulation. As another modulation system, in an FSK (Frequency Shift Keying) system for changing a frequency, a slot gap 513 is long with respect to a wobble cycle, and synchronization of a PLL circuit is relatively hardly obtained. Therefore, as 10 in the present embodiment, when address information is recorded by wobble phase modulation, there is attained advantageous effect that a slot gap is narrow, and wobble signal synchronization is easily obtained. As shown in FIG. 76, although binary data "1" or 15 "0" is assigned to the 1-address bit area 511, a method for allocating bits in the present embodiment is shown in FIG. 77. As shown on the left side of FIG. 77, a wobble pattern, which first wobbles from the start position of one wobble to the outer periphery side, is 20 referred to as an NPW (Normal Phase Wobble), and data "0" is arranged. As shown at the right side, a wobble pattern which first wobbles from the start position of one wobble to the inner periphery side is referred to as an IPW (Invert Phase Wobble), and data "1" is 25 arranged. A description will be given with respect to an address information recording format using wobble modulation in an H format of a write-once type information storage medium according to the invention. An address information setting method using wobble modulation in the present embodiment is featured in 5 that "allocation is carried out in units of the sync frame length 433" shown in FIG. 73. As shown in FIGS. 62A and 62B, one sector is composed of 26 sync frames, and, as is evident from FIG. 56, one ECC block is formed of 32 physical sectors. Thus, one ECC block 10 is composed of 32 physical sectors and is composed of 832 (= 26 x 327) sync frames. As shown in FIG. 73, a length of the guard areas 442 to 468 which exist between the ECC blocks 411 to 418 coincides with one sync frame length 433, and thus, a length obtained by 15 adding one guard area 462 and one ECC block 411 to each other is composed of 832 + 1 = 833 sync frames. Prime factorization can be carried out into 833 = 7 x 17 x 7, and thus, a structural allocation utilizing this feature is provided. That is, a basic unit of data 20 capable of writing an area equal to a length of an area obtained by adding one guard area and one ECC block to each other is defined as a data segment 531 (A structure in the data segment 490 shown in FIG. 75 coincides with one another regardless of the read-only 25 type information storage medium, the rewritable-type information storage medium, or the write-once type information storage medium); an area having the same length as a physical length of one data segment 490 is divided into "seven" physical segments, and address information is recorded in advance in the form of wobble modulation on a physical segment by segment 5 basis. A boundary position relevant to the data segment 490 and a boundary position relevant to a physical segment do not coincide with each other, and are shifted by an amount described later. Further, wobble data is divided into 17 WDU (Wobble Data Units), 10 respectively, on a physical segment by segment basis. From the above formula, it is evident that seven sync frames are arranged to a length of one wobble data unit, respectively. Thus, a physical segment is composed of 17 wobble data units, and seven physical 15 segment lengths are adjusted to conform with a data segment length, thereby making it easy to allocate a sync frame boundary and detect a sync code in a range encompassing guard areas 442 to 468. Each of the wobble data units #0 560 to #11 571 is 20 composed of: a modulation area 598 for 16 wobbles; and non-modulation areas 592 and 593 for 68 wobbles, as shown in FIGS. 78A to 78D. The present embodiment is featured in that an occupying ratio of the nonmodulation areas 592 and 593 with respect to a 25 modulation area is significantly large. In the non-modulation areas 592 and 593, a group area or a land area always wobbles at a predetermined frequency, and thus, a PLL (Phase Locked Loop) is applied by u L i l i z i n y LliH nun=iuodulation areas 592 and 593, making it possible to stably sample (generate) a reference clock when reproducing a recording mark recorded in the 5 information storage medium or a recording reference clock used at the time of new recording. Thus, in the present embodiment, an occupying ratio of the nonmodulation areas 592 and 593 with respect to a modulation area 598 is significantly increased, thereby 10 making it possible to remarkably improve the precision of sampling (generating) a recording reference clock and remarkably improving the stability of the sampling (generation). That is, in the case where phase modulation in wobbles has been carried out, if a 15 reproduction signal is passed through a band path filter for the purpose of waveform shaping, there appears a phenomenon that a detection signal waveform amplitude after shaped is reduced before and after a phase change position. Therefore, there is a problem 20 that, when the frequency of a phase change point due to phase modulation increases, a waveform amplitude change increases, and the above clock sampling precision drops; and, conversely, if the frequency of a phase change point in a modulation area is low, a bit shift 25 at the time of wobble address information detection is likely to occur. Thus, in the present embodiment, there is attained advantageous effect that a modulation area and a non-modulation area due to phase modulation configured, and an occupying ratio of the nonmodulation area is increased, thereby improving the above clock sampling precision. In the present 5 embodiment, a position of switching the modulation area and the non-modulation area can be predicted in advance. Thus, a reproduction signal is gated to obtain a signal from the non-modulation area, making it possible to carry out the above clock sampling from 10 that detection signal. In addition, in the case where the recording layer 3-2 is composed of an organic dye recording material using a principle of recording according to the present embodiment, a wobble signal is comparatively hardly taken in the case of using the 15 pre-groove shape/dimensions described in "3-2-D] Basic characteristics relevant to pre-groove shape/dimensions in the present embodiment" in "3-2) Description of basic characteristics common to organic dye film in the present embodiment". In consideration of this 20 situation, the reliability of wobble signal detection is improved by significantly increasing an occupying ratio of the non-modulation areas 590 and 591 with respect to a modulation area, as described above. At the boundary between the non-modulation areas 592 and 25 593 and the modulation area 598, an IPW area is set as a modulation start mark of the modulation area 598 by using four wobbles or six wobbles. At a wobble data section shown in FIGS. 78C and 78D, allocation is carried out so that wobble address areas (address bits #2 to #0) wobble-modulated immediately after detecting the IPW area which is this modulation start mark. 5 FIGS. 78A and 78B each show the contents in a wobble data unit #0 560 which corresponds to a wobble sync area 580 shown in FIG. 79 (c) described later; and FIGS. 78C and 78D each show the contents in a wobble data unit which corresponds to a wobble data section 10 from segment information 727 to a CRC code 726 shown in FIG. 79 (c). FIGS. 78A and 78C each show a wobble data unit which corresponds to a primary position 701 in a modulation area described later; and FIGS. 78B and 78D each show a wobble data unit which corresponds to a 15 secondary position 702 in a modulation area. As shown in FIGS. 78A and 78B, in a wobble sync area 580, six wobbles are allocated to the IPW area, and four wobbles are allocated to an NPW area surrounded by the IPW area. As shown in FIGS. 78C and 78D, four wobbles are 20 allocated to a respective one of the IPW area and all of the address bit areas #2 to #0 in the wobble data section. FIG. 79 shows an embodiment relating to a data structure in wobble address information in a write-once 25 type information storage medium. For the sake of comparison, FIG. 79 (a) shows a data structure in wobble address information of a rewritable-type information storage medium. FIGS. 79 (a) and 79 (c) show two embodiments relating to a data structure in wobble address information in the write-once type information storage medium. 5 In a wobble address area 610, three address bits are set by 12 wobbles (referring to FIG. 76). Namely, one address bit is composed of four continuous wobbles. Thus, the present embodiment employs a structure in which address information is arranged to be distributed 10 on three by three address bit basis. When the wobble address information 610 is intensively recorded at one site in an information storage medium, it becomes difficult to detect all information when dust or scratch adheres to the medium surface. As in the 15 present embodiment, there is attained advantageous effect that: wobble address information 610 is arranged to be distributed on a three by three address bit (12 wobbles) basis included in one of the wobble data units 560 to 576; and a set of information is recorded 20 on an integer multiple by multiple address bit basis of three address bits, enabling information detection of another item of information even in the case where it is difficult to detect information in one site due to dust or scratch. 25 As described above, the wobble address information 610 is arranged to be distributed, and the wobble address information 610 is completely arranged on a one by one physical segment basis, thereby making it possible to identify address information on a physical segment by segment basis, and thus, identify a current position in physical segment units every time an 5 information recording/reproducing apparatus provides an access. In the present embodiment, an NRZ technique is employed as shown in FIG. 76, and thus, a phase does not change in four continuous wobbles in the wobble 10 address area 610. A wobble sync area 580 is set by utilizing this characteristic. That is, a wobble pattern which is hardly generated in the wobble address information 610 is set with respect to the wobble sync area 580, thereby facilitating allocation position 15 identification of the wobble sync area 580. The present embodiment is featured in that, with respect to wobble address areas 586 and 587 in which one address bit is composed of four continuous wobbles, one address bit length is set at a length other than four wobbles 20 at a position of the wobble sync area 580. That is, in the wobble sync area 580, as shown in FIGS. 78A and 78B, an area (IPW area) in which a wobble bit is set to "1" is set as a wobble pattern change which does not occur in the wobble data section as shown in FIGS. 78C 25 and 78D such as "six wobble —» four wobbles —» six wobbles". When a method for changing a wobble cycle as described above is utilized as a specific method for setting a wobble pattern which can be hardly generated in the wobble data section with respect to the wobble sync area 580, the following advantageous effects can be attained: 5 1) Wobble detection (wobble signal judgment) can be stably continued without distorting PLL relating to the slot position 512 (FIG. 76) of a wobble which is carried out in the wobble signal detector unit 135 shown in FIG. 11; and 10 2) A wobble sync area 580 and modulation start marks 561 and 562 can be easily detected due to a shift of an address bit boundary position generated in the wobble signal detector unit 135 shown in FIG. 11. As shown in FIGS. 78A to 78D, the present 15 embodiment is featured in that the wobble sync area 580 is formed in 12 wobble cycles, and a length of the wobble sync area 580 is made coincident with three address bit lengths. In this manner, all the modulation areas (for 16 wobbles) in one wobble data 20 unit #0 560 are arranged to the wobble sync area 580, thereby improving detection easiness of the start position of wobble address information 610 (allocation position of wobble sync area 580). This wobble sync area 580 is arranged in the first wobble data unit in a 25 physical segment. Thus, there is attained advantageous effect that the wobble sync area 580 is arranged to the start position in a physical segment, whereby a boundary position of the physical segment can be easily sampled merely by detecting a position of the wobble sync area 580. As shown in FIGS. 78C and 78D, in wobble data 5 units #1 561 to #11 571, the IPW area (refer to FIG. 77) is arranged as a modulation start mark at the start position, the area preceding address bits #2 to #0. The waveform of NPW is continuously formed in the non-modulation areas 592 and 593 arranged at the 10 preceding position. Thus, the wobble signal detector unit 135 shown in FIG. 11 detects a turning point from NPW to IPW is detected, and samples the position of the modulation start mark. As a reference, the contents of wobble address 15 information 610 contained in a rewritable-type information storage medium shown in FIG. 79 (a) are as follows: 1) Physical segment address 601 - Information indicating a physical segment number 20 in a track (within one cycle in an information storage medium 221); 2) Zone address 602 - This address indicates a zone number in the information storage medium 221; and 25 3) Parity information 605 - This information is set for error detection at the time of reproduction from the wobble address information 610; 14 address bits from reserved information 604 to the zone address 602 are individually added in units of address bits; and a display as to whether or not a result of the addition 5 is an even number or an odd number is made. A value of the parity information 605 is set so that a result obtained by taking exclusive OR in units of address bits becomes "1" with respect to a total of 15 address bits including one address bit of this address parity 10 information 605. 4) Unity area 608 - As described previously, each wobble data unit is set so as to be composed of a modulation area 598 for 16 wobbles and non-modulation areas 592 and 593 for 15 68 wobbles, and an occupying ratio of the nonmodulation areas 592 and 593 with respect to the modulation area 598 is significantly increased. Further, the precision and stability of sampling (generation) of a reproducing reference clock or a 20 recording reference clock is improved more remarkably by increasing the occupying ratio of the non-modulation areas 592 and 593. The NPW area is fully continuous in a unity area 608, and is obtained as a non-modulation area having its uniform phase. 25 FIG. 79 (a) shows the number of address bits arranged to each item of the above described information. As described above, the wobble address information 610 is divided on a three by three address bits, and the divided items of the information are arranged to be distributed in each wobble data unit. Even if a burst error occurs due to the dust or scratch 5 adhering to a surface of an information storage medium, there is a very low probability that such an error propagates across the wobble data units which are different from each other. Therefore, a contrivance is made so as to reduce to the minimum the count 10 encompassing the different wobble data units as locations in which the same information is recorded and to match the turning point of each items of information with a boundary position of a wobble data unit. In this manner, even if a burst error occurs due to the 15 dust or scratch adhering to a surface of an information storage medium, and then, specific information cannot be read, the reliability of reproducing of wobble address information is improved by enabling reading of another item of information recorded in another one of 20 the wobble data units. As shown in FIGS. 79 (a) to 79 (d), the present embodiment is featured in that the unity areas 608 and 609 are arranged at the end in the wobble address information 610. As described above, in the unity 25 areas 608 and 609, a wobble waveform is formed in the shape of NPW, and thus, the NPW continuously lasts in substantially three continuous wobble data units. There is attained advantageous effect that the wobble signal detector unit 135 shown in FIG. 11 makes a search for a location in which NPW continuously lasts in a length for three wobble data units 576 by 5 utilizing this feature, thereby making it possible to easily sample a position of the unity area 608 arranged at the end of the wobble address information 610, and to detect the start position of the wobble address information 610 by utilizing the positional 10 information. From among a variety of address information shown in FIG. 79 (a), a physical segment address 601 and a zone address 602 indicate the same values between the adjacent tracks, whereas a value changes between the 15 adjacent tracks in a groove track address 606 and a land track address 607. Therefore, an indefinite bit area 504 appears in an area in which the groove track address 606 and the land track address 607 are recorded. In order to reduce a frequency of this 20 indefinite bit, in the present embodiment, an address (number) is displayed by using a gray code with respect to the groove track address 606 and the land track address 607. The gray code denotes a code in the case where a code after converted when an original value 25 changes by "1" only changes by "one bit" anywhere. In this manner, the indefinite bit frequency is reduced, making it possible to detect and stabilize a reproduction signal from a recording mark as well as a wobble detecting signal. As shown in FIGS. 79 (b) and 79 (c), in a writeonce type information storage medium as well, as in the 5 rewritable-type information storage medium, a wobble sync area 580 is arranged at the start position of a physical segment, thereby making it easy to detect the start position of the physical segment or a boundary position between the adjacent segments. Type 10 identification information 721 on the physical segment shown in FIG. 79B indicates an allocation position in the physical segment as in the wobble sync pattern contained in the above described wobble sync area 580, thereby making it possible to predict in advance an 15 allocation location of another modulation area 598 in the same physical segment and to prepare for next modulation area detection. Thus, there is attained advantageous effect that the precision of signal detection (judgment) in a modulation area can be 20 improved. Specifically, When type identification information 721 on a physical segment is set to "0", it denotes that all the items of information in the physical segment shown in FIG. 81 (b) are arranged at a primary position or that 25 a primary position and a secondary position shown in FIG. 81 (d) are mixed; and When type identification information 721 of a physical segment is set to "1", all items of information in a physical segment are arranged at a secondary position, as shown in FIG. 81 (c). According to another embodiment relevant to the 5 above described embodiment, it is possible to indicate an allocation location of a modulation area in a physical segment by using a combination between a wobble sync pattern and type identification information 721 on a physical segment. By using the combination of 10 the two types of information described previously, three or more types of allocation patterns of modulation areas shown in FIGS. 81 (b) to 81 (d) can be expressed, making it possible to provide a plurality of allocation patterns of the modulation areas. While the 15 above described embodiment shows an allocation location of a modulation area in a physical segment which includes a wobble sync area 580 and type identification information 721 on a physical segment, the invention is not limited thereto. For example, as another 20 embodiment, the wobble sync area 580 and the type identification information 721 on the physical segment may indicate an allocation location of a modulation area in a next physical segment. By doing this, in the case where tracking is carried out continuously along a 25 groove area, there is attained advantageous effect that the allocation location of the modulation area in the next physical segment can be identified in advance, and a long preparation time for detecting a modulation area can be taken. Layer number information 722 in a write-once type information storage medium shown in FIG. 79 (b) 5 indicates either of the recording layers from among a single-sided single-layer or a single-sided doublelayer. This information denotes: - "LO later" in the case of a single-sided singlelayer medium or a single-sided double-layer medium when 10 "0" is set (a front layer at the laser light beam incident side); and - "LI layer" of a single-sided double-layer when "1" is set (a rear layer in viewed from the laser light beam incident side). 15 Physical segment sequence information 724 indicates an allocation sequence of relative physical segments in the same physical segment block. As is evident as compared with FIG. 79 (a), the start position of the physical segment sequence information 20 724 contained in wobble address information 610 coincides with that of a physical segment address 601 contained in a rewritable-type information storage medium. The physical segment sequence information position is adjusted to conform with the 25 rewritable-type medium, thereby making it possible to improve compatibility between medium types and to share or simplify an address detection control program using a wobble signal in an information recording/reproducing apparatus in which both of a rewritable-type information storage medium and a write-once type information storage medium can be used. 5 A data segment address 725 shown in FIG. 79 (b) describes address information on a data segment in numbers. As has already been described, in the present embodiment, one ECC block is composed of 32 sectors. Therefore, the least significant five bits of a 10 physical sector number of a sector arranged at the beginning in a specific ECC block coincides with that of a sector arranged at the start position in the adjacent ECC block. In the case where a physical sector number has beet set so that the least 15 significant five bits of the physical sector number of a sector arranged in an ECC block are "00000", the values of the least significant six bits or more of the physical sector numbers of all the sectors which exist in the same ECC block coincide with each other. 20 Therefore, the least significant five bit data of the physical sector number of the sectors which exist in the same ECC block is eliminated, and address information obtained by sampling only the least significant six bits or more is defined as an ECC block 25 address (or ECC block address number). A data segment address 725 (or physical segment block number information) recorded in advance by wobble modulation coincides with the above ECC block address. Thus, when positional information on a physical segment block due to wobble modulation is indicated by a data segment address, there is advantageous effect that a data 5 amount decreases on five by five bit basis as compared with when the address is displayed by a physical sector number, simplifying current position detection at the time of an access. A CRC code 726 shown in FIGS. 79 (b) and 79 (c) is 10 a CRC code (error correction code) arranged to 24 address bits from physical segment type identification information 721 to the data segment address 725 or a CRC code arranged to 24 address bits from segment information 727 to the physical segment sequence 15 information 724. Even if a wobble modulation signal is partially mistakenly read, this signal can be partially corrected by this CRC code 726. In a write-once type information storage medium, an area corresponding to 15 address bits is arranged to 20 the unity area 609, and an NPW area is fully arranged in five wobble data units 12 to 16 (the modulation area 598 does not exist). A physical segment block address 728 shown in FIG. 79 (c) is an address set for each physical segment 25 block which configure one unit from seven physical segments, and a physical segment block address relevant to the first segment block in the data lead-in area DTRDI is set to "1358h". The values of the physical segment block addresses are sequentially added one by one from the first physical segment block contained in the data lead-in area DTLDI to the last physical 5 segment block contained in the data lead-out area DTLDO, including the data area DTA. The physical segment sequence information 724 denotes the sequence of each of the physical segments in one physical segment block, and "0" is set to the 10 first physical segment, and "6" is set to the last physical segment. The embodiment shown in FIG. 79 (c) is featured in that the physical segment block address 728 is arranged at a position which precedes the physical segment 15 sequence information 724. For example, as in the RMD field 728 shown in FIG. 53, address information is often managed by this physical segment block address. In the case where an access is provided to a predetermined segment block address in accordance with 20 these items of management information, first, the wobble signal detector unit 135 shown in FIG. 11 detects a location of the wobble sync area 580 shown in FIG. 79 (c), and then, sequentially decodes items of information recorded immediately after the wobble sync 25 area 580. In the case where a physical segment block address exists at a position which precedes the physical segment sequence information 724, first, the physical segment block address is decoded, and it is possible to judge whether or not a predetermined physical segment block address exists without decoding the physical segment sequence information 724. Thus, 5 there is advantageous effect that access capability using a wobble address is improved. The segment information 727 is composed of type identification information 721 and a reserved area 723. The type identification information 721 denotes an 10 allocation location of a modulation area in a physical segment. In the case where the value of this type identification information 721 is set to "Ob", it denotes a state shown in FIG. 81 (b) described layer. In the case where the information is set to "Ib", it 15 denotes a state shown in FIG. 81 (c) or FIG. 81 (d) described later. The present embodiment is featured in that type information identification 721 is arranged immediately after the wobble sync area 580 in FIG. 79 (c). As 20 described above, first, the wobble signal detector unit 135 shown in FIG. 11 detects a location of the wobble sync area 580 shown in FIG. 79 (c), and then, sequentially decodes the items of information recorded immediately after the wobble sync area 580. Therefore, 25 the type identification information 721 is arranged immediately after the wobble sync area 580, thereby enabling an allocation location check of a modulation area in a physical segment immediately. Thus, high speed access processing using a wobble address can be achieved. In the write-once type information storage medium 5 according to the present embodiment, a recording mark is formed on a groove area, and a CLV recording system is employed. In this case, as described previously, a wobble slot position is shifted between the adjacent tracks, and thus, interference between the adjacent 10 wobbles is likely to occur with a wobble reproduction signal. In order to eliminate this effect, in the present embodiment, a contrivance is made to shift a modulation area so that modulation areas do not overlap each other between the adjacent tracks. 15 Specifically, as shown in FIG. 80, a primary position 701 and a secondary position 702 can be set in an allocation location of a modulation area. Basically, assuming that after allocation has been fully carried out in the primary position, there occurs 20 a location in which modulation areas partially overlap between the adjacent tracks, there is employed a method for partially shift the modulation area to the secondary position. For example, in FIG. 80, when a modulation area of a groove area 505 is set at the 25 primary position, a modulation area of the adjacent groove area 502 and a modulation area of a groove area 506 partially overlap on each other. Thus, the modulation area of the groove area 505 is shifted to the secondary position. In this manner, there is attained advantageous effect that a wobble address can be stably reproduced by preventing the interference 5 between the modulation areas of the adjacent tracks in a reproduction signal from a wobble address. The specific primary position and secondary position relating to a modulation area is set by switching an allocation location in the same wobble 10 data unit. In the present embodiment, an occupying ratio of a non-modulation area is set to be higher than a modulation area so that, the primary position and the secondary position can be switched merely by making a mere allocation change in the same wobble data unit. 15 Specifically, in the primary position 701, as shown in FIGS. 78 (a) and 78 (c), the modulation area 598 is arranged at the start position in one wobble data unit. In the secondary position 702, as shown in FIGS. 78 (b) and 78 (d), the modulation area 598 is arranged at the 20 latter half position in one of the wobble data unit 560 to 571. A coverage of the primary position 701 and the secondary position 702 shown in FIGS. 78 (a) to 78 (d), i.e., a range in which the primary position or the 25 secondary position continuously lasts is defined in the rage of physical segments in the present embodiment. That is, as shown in FIGS. 81 (b) to 81 (d) , after three types (plural types) of allocation patterns of modulation areas in the same physical segment have been provided, when the wobble signal detector unit 135 shown in FIG. 11 identifies an allocation pattern of a 5 modulation area in a physical segment from the information contained in the type identification information 721 on a physical segment, the allocation location of another modulation area 598 in the same physical segment can be predicted in advance. As a 10 result, there is attained advantageous effect that preparation for detecting a next modulation area can be made, thus making it possible to improve the precision of signal detection (judgment). FIG. 81 (b) shows allocation of wobble data units 15 in a physical segment, wherein the number described in each frame indicate wobble data unit numbers in the same physical segment. A 0-th wobble data unit are referred to as a sync field 711 as indicated at a first stage. A wobble sync area exists in a modulation area 20 in this sync field. First to eleventh wobble data units are referred to as an address field 712. Address information is recorded in a modulation area contained in this address field 712. Further, in twelfth to sixteenth wobble data units, all of the wobble patterns 25 are formed in an NPW unity field 713. A mark "P" described in FIGS. 81 (b), 81 (c) and 81 (d) indicates that a modulation area is set at a primary position in a wobble data unit; and a mark "S" indicates that a modulation area is set at a secondary position in a wobble data unit. A mark "U" indicates that a wobble data unit is included in a unity field 5 713, and a modulation area does not exist. An allocation pattern of a modulation area shown in FIG. 81 (b) indicates that all the areas in a physical segment are set at the primary position; and an allocation pattern of a modulation area shown in 10 FIG. 81 (c) indicates all areas in a physical segment are set at the secondary position. In FIG. 81 (d), the primary position and the secondary position are mixed in the same physical segment; a modulation area is set at the primary position in each of 0-th to fifth wobble 15 data units, and a modulation area is set at the secondary position in each of sixth to eleventh wobble data units. As shown in FIG. 81 (d), the primary positions and the secondary positions are half divided with respect to an area obtained by adding a sync field 20 711 and an address field 712, thereby making it possible to finely prevent an overlap of modulation areas between the adjacent tracks. Now, a description will be given with respect to a method for recording the data segment data described 25 previously with respect to the physical segment or the physical segment block in which address information is recorded in advance by wobble modulation described above. Data is recorded in recording cluster units serving as units of continuously recording data in both of a rewritable-type information storage medium and a write-once type information storage medium. FIGS. 82A 5 and 82B show a layout in this recording cluster. In recording clusters 540 and 542, one or more (integer numbers) of data segments continuously lasts, and an expanded guard field 528 or 529 is set at the beginning or at the end of the segment. The expanded guard 10 fields 528 and 529 are set in the recording clusters 540 and 542 so as to be physically overlapped and partially overwritten between the adjacent recording clusters so as not to produce a gap between the adjacent recording clusters when data is newly 15 additionally written or rewritten in units of the recording clusters 540 and 542. As the position of each of the expanded guard fields 528 and 529 set in the recording clusters 540 and 542, in the embodiment shown in FIG. 82A, the expanded guard field 528 is 20 arranged at the end of the recording cluster 540. In the case where this method is used, the expanded guard field 528 follows a post amble area 526 shown in FIG. 83 (a). Thus, in particular, in the write-once type information storage medium, the post-amble area 25 526 is not mistakenly damaged at the time of rewriting; protection of the post-amble area 526 at the time of rewriting can be carried out; and the reliability of position detection using the post amble area 526 at the time of data reproduction can be arranged. As another embodiment, as shown in FIG. 82B, the expanded guard field 529 can also be arranged at the beginning of the 5 recording cluster 542. In this case, as is evident from a combination of FIG. 82B and FIGS. 83 (a) to 83 (f), the expanded guard field 529 immediately precedes a VFO area 522. Thus, at the time of rewriting or additional writing, the VFO area 522 can 10 be sufficiently taken long, and thus, a PLL lead-in time relating to a reference clock at the time of reproduction of a data field 525 can be taken long, making it possible to improve the reliability of reproduction of data recorded in the data field 525. 15 In this way, there is attained advantageous effect that a structure composed of data segments in the case where one or more recording clusters denote writing units is provided, thereby making it possible to facilitate a mixing recording process with respect to the same 20 information storage medium, PC data (PC files) of which a small amount of data is often rewritten many times and AV data (AV file) of which a large amount of data is continuously recorded one time. That is, with respect to data used for a personal computer, a 25 comparatively small amount of data is often rewritten many times. Therefore, a recording method suitable for PC data is obtained by minimally setting data units of rewriting or additional writing. In the present embodiment, as shown in FIG. 56, an ECC block is composed of 32 physical sectors. This, a minimum unit for efficiently carrying out rewriting or additional 5 writing is obtained by carrying out rewriting or additional writing in data segment units including only one ECC block. Therefore, a structure in the present embodiment in which one or more data segments are included in a recording cluster which denotes rewriting 10 units or additional writing units is obtained as a recording structure suitable for PC data (PC files). In AV (Audio Video) data, it is necessary to continuously record a very large amount of video image information and voice information smoothly without any 15 problem. In this case, continuously recorded data is collectively recorded as one recording cluster. At the time of AV data recording, when a random shift amount, a structure in a data segment, or a data segment attribute and the like is switched on a data segment by 20 segment basis configuring one recording cluster, a large amount of time is required for such a switching process, making it difficult to carry out a continuous recording process. In the present embodiment, as shown in FIGS. 82A and 82B, it is possible to provide a 25 recording format suitable for AV data recording for continuously recording a large amount of data by configuring a recording cluster while data segments in the same format (without changing an attribute or a ransom shift amount and without inserting specific information between data segments) are continuously arranged. In addition, a simplified structure in a 5 recording cluster is achieved, and simplified recording control circuit and reproduction detector circuit are achieved, making it possible to reduce the price of an information recording/reproducing apparatus or an information reproducing apparatus. A data structure in 10 recording cluster 540 in which data segments (excluding the expanded guard field 528) in the recording cluster shown in FIGS. 82A and 82B are continuously arranged is completely identical to those of the read-only information storage medium shown in FIG. 73 (b) and the 15 write-once type information storage medium shown in FIG. 73 (c). In this way, a common data structure is provided among all of the information storage mediums regardless of the read-only type, the write-once type, or the rewritable-type, thus allocating medium 20 compatibility. In addition, a detector circuit of the information recording/reproducing apparatus or the information reproducing apparatus whose compatibility has been arranged can be used in common; high reliability of reproduction can be arranged; and price 25 reduction can be achieved. By employing the structure shown in FIGS. 82A and 82B, random shift amounts of all the data segments inevitably coincide with each other in the recording cluster. In the rewritable-type information medium, a recording cluster is recorded by random shifting. In the present embodiment, the random shift amounts of all 5 the data segments coincide with each other in the same recording cluster 540. Thus, in the case where reproduction has been carried out across the different data segments from each other in the same recording cluster 540, there is no need for synchronization 10 adjustment (phase resetting) in a VFO area (reference numeral 522 in FIG. 83 (d)), making it possible to simplify a reproduction detector circuit at the time of continuous reproduction and to allocate high reliability of reproduction detection. 15 FIGS. 83 shows a method for recording data to be rewritably recorded in a rewritable-type information storage medium. Now, although a description will be given while focusing on a rewritable-type information storage medium, it should be noted that an additional 20 writing method relevant to a write-once type information storage medium is basically identical to the above recording method. A layout in the recording cluster in a write-once type information storage medium according to the present embodiment will be described 25 in way of example employing a layout shown in FIG. 82A. The present embodiment is not limited thereto, and a layout shown in FIG. 82B may be employed for a rewritable-type information storage medium. In the present embodiment, rewriting relating to rewritable data is carried out in units of the recording clusters 540 and 541 shown in FIGS. 82B and 83 (e). As 5 described later, one recording cluster is composed of one or more data segments 529 to 531 and an expanded guard field 528 arranged at the end. That is, the start position of one recording cluster 631 coincides with that of the data segment 531, and the cluster 10 starts from the VFO area 522. In the case where a plurality of data segments 529 and 530 are continuously recorded, the plurality of data segments 529 and 530 are continuously arranged in the same recording cluster 531. In addition, the buffer area 547 which exists at 15 the end of the data segment 529 and the VFO area 532 which exists at the beginning of a next data segment continuously last, and thus, a phase (of a recording reference clock) at the time of recording) between these areas coincides with one another. When 20 continuous recording terminates, an expanded guard area 528 is arranged at the end position of the recording cluster 540. The data size of this expanded guard area 528 is equal to the size for 24 data bytes as data before modulated. 25 As is evident from a correlation between FIGS. 83 (a) and 83 (c), rewritable-type guard areas 461 and 462 each include: post amble areas 546 and 536; extra areas 544 and 534; buffer areas 547 and 537; VFO areas 532 and 522; and pre-sync areas 533 and 523, and an expanded guard field 528 is arranged only in location in which continuous recording terminates. The present 5 embodiment is featured in that rewriting or additional writing is carried out so that the expanded guard area 528 and the succeeding VFO area 522 partially overlap each other at a duplicate site 591 at the time of rewriting. By rewriting or additional writing while 10 partial duplication is maintained, it is possible to prevent a gap (area in which no recording mark is formed) from being produced between the recording clusters 540 and 541. In addition, a stable reproduction signal can be detected by eliminating 15 inter-layer cross talk in an information storage medium capable of carrying out recording in a single-sided double recording layer. The data size which can be rewritten in one data segment in the present embodiment is 67 + 4 + 77376 + 2 20 + 4 + 16 = 77469 (data bytes). One wobble data unit 560 is 6 + 4 + 6 + 68 = 84 (wobbles). One physical segment 550 is composed of 17 wobble data units, and a length of seven physical segments 550 to 556 coincides with that of one data segment 531. Thus, 84 x 17 x 7 = 25 9996 (wobbles) are arranged in the length of one data segment 531. Therefore, from the above formula, 77496/9996 =7.75 (data bytes/wobble) corresponds to one wobble. As shown in FIG. 84, an overlap portion of the succeeding VFO area 522 and the expanded guard field 528 follows 24 wobbles from the start position of a 5 physical segment, and the starting 16 wobbles of a physical segment 550 are arranged in a wobble sync area 580, and the subsequent 68 wobbles are arranged in a non-modulation area 590. Therefore, an overlap portion of the VFO area 522 which follows 24 wobbles and the 10 expanded guard field 528 is included in the nonmodulation area 590. In this way, the start position of a data segment follows the 24 wobbles from the start position of a physical segment, whereby the overlap portion is included in the non-modulation area 590. In 15 addition, a detection time and a preparation time for recording process of the wobble sync area 580 can be sufficiently taken, and thus, a stable and precise recording process can be guaranteed. A phase change recording film is used as a 20 recording film of the rewritable-type information storage medium in the present embodiment. In the phase change recording film, degradation of the recording film starts in the vicinity of the rewriting start/end position. Thus, if recording start/recording end at 25 the same position is repeated, there occurs a restriction on the number of rewritings due to the degradation of the recording film. In the present embodiment, in order to alleviate the above described problem, at the time of rewriting, J^+i/l2 data bytes are shifted as shown in FIG. 84, and the recording start position is shifted at random. 5 Although the start position of the expanded guard field 528 coincides with that of the VFO area 522 in order to explain a basic concept in FIGS. 83 (c) and 83 (d), strictly, the start position of the VFO area 522 is shifted at random, as shown in FIG. 84, in the 10 present embodiment. A phase change recording film is used as a recording film in a DVD-RAM disk which is a current rewritable-type information storage medium as well, the start/end positions of recording is shifted at random 15 for the purpose of improving the rewriting count. The maximum shift amount range when random shifting has been carried out in the current DVD-RAM disk is set to 8 data bytes. A channel bit length (as data after modulated, to be recorded in a disk) in the current 20 DVD-RAM disk is set to 0.143 \|^m on average. In the rewritable-type information storage medium according to the present embodiment, an average length of channel bits is obtained as (0.087 + 0.093)/2 = 0.090 (\m) . In the case where a length of a physical shift range is 25 adjusted to conform with the current DVD-RAM disk, by using the above value, the required minimal length serving as a random shift range in the present embodiment is obtained as: 8 bytes x (0.143 \|am/0.090 jam) = 12.7 bytes In the present embodiment, in order to allocate easiness of a reproduction signal detecting process, 5 the unit of random shift amount has been adjusted to conform with "channel bits" after modulated. In the present embodiment, ETM modulation (Eight to Twelve modulation) for converting 8 bits to 12 bits is used, and thus, formula expression which indicates a random 10 shift amount is designated by Jm/12 (data bytes) while a data byte is defined as a reference. Using the value of the above formula, a value which can be taken by Jm is 12.7 x 12 = 152.4, and thus, Jm ranges 0 to 152. For the above described reason, in the range meeting 15 the above formula, a length of the random shift range coincides with the current DVD-RAM disk, and the rewriting count similar to the current DVD-RAM disk can be guaranteed. In the present embodiment, a margin is slightly provided with respect to the required minimal 20 length in order to allocate the current or more rewriting count, and the length of the random shift range has been set to 14 (data bytes). From these formulas, 14 x 12 = 168 is established, and thus, a value which can be taken by Jm has been set in the 25 range of 0 to 167. As described above, the random shift amount is defined in a range which is wider than Jm/12 (0 range relevant to the random shift amount coincides with that of the current DVD-RAM. Thus, there is attained advantageous effect that the repetition recording count similar to that of the current DVD-RAM 5 can be guaranteed. In FIG. 83 (c), the lengths of the buffer area 547 and the VFO area 532 in the recording cluster 540 become constant. As is evident from FIG. 82 (a) as well, the random shift amount Jm of all the data 10 segments 529 is obtained as the same value everywhere in the same recording cluster 540. In the case of continuously recording one recording cluster 540 which includes a large amount of data segments, a recording position is monitored from a wobble. That is, a 15 position of the wobble sync area 580 shown in FIGS. 79 (a) to 79 (c) is detected, and, in the non-modulation areas 592 and 593 shown in FIGS. 78 (c) and 78 (d), the check of the recording position on the information storage medium is made at the same time as recording 20 while the number of wobbles is counted. At this time, a wobble slip (recording at a position shifted by one wobble cycle) occurs due to mistaken wobble count or rotation non-uniformity of a rotary motor which rotates the information storage medium, and the recording 25 position on the information storage medium is rarely shifted. The information storage medium according to the present embodiment is featured in that, in the case where a recording position shift generated as described above has been detected, adjustment is made in the rewritable-type guard area 461 shown in FIG. 83 (a), and recording timing correction is carried out in the 5 guard area 461. Now, an H format will be described here. This basic concept is employed in a B format, described later. In FIGS, 83 (a) to 83 (f), although important information for which bit missing or bit duplication cannot be allowed is recorded in a 10 postamble area 546, an extra area 544, and a pre-sync area 533, a specific pattern is repeated in the buffer area 547 and the VFO area 532. Thus, as long as this repetition boundary position is arranged, missing or duplication of only one pattern is allowed. Therefore, 15 in the present embodiment, in particular, adjustment is made in the buffer area 547 or the VFO area 532, and recording timing correction is carried out. As shown in FIG. 84, in the present embodiment, an actual start point position defined as a reference of 20 position setting is set so as to match a position of wobble amplitude "0" (wobble center). However, the position detecting precision of a wobble is low, and thus, in the present embodiment, the actual start point position allows a shift amount up to a maximum of ±1 25 data byte", as "±1 max" in FIG. 84 is described. In FIGS. 83 (a) to 83 (f) and 84, the random shift amount in the data segment 530 is defined as Jm (as described above, the random shift amounts of all the data segments 529 coincide with each other in the recording cluster 540); and the random shift amount of the data segment 531 to be additionally written is 5 defined as Jm+i- As a value which can be taken by Jm and Jm+i shown in the above formula, for example, when an intermediate value is taken, Jm = Jm+]_ = 84 is obtained. In the case where the positional precision of an actual start point is sufficiently high, the 10 start position of the expanded guard field 528 coincides with that of the VFO area 522, as shown in FIGS. 83 (c) and 83 (d). In contrast, after the data segment 530 is recorded at the maximum back position, in the case 15 where the data segment 531 to be additionally written or rewritten has then been recorded in the maximum front position, the start position of the VFO area 522 may enter a maximum 15 data bytes in the buffer area 537. Specific important information is recorded in the 20 extra area 534 that immediately precedes the buffer area 537. Therefore, in the present embodiment, a length of the buffer area 537 requires 16 data bytes or more. In the embodiment shown in FIG. 83 (c), a data size of the buffer area 537 is set to 15 data bytes in 25 consideration of a margin of one data byte. As a result of a random shift, if a gap occurs between the expanded guard area 528 and the VFO area 522, in the case where a single-sided double recording layer structure has been employed, there occurs an inter-layer crosstalk at the time of reproduction due to that gap. Thus, even if a random shift is carried 5 out, a contrivance is made such that the expanded guard field 528 and the VFO area 522 partially overlap each other, and a gap is not produced. Therefore, in the present embodiment, it is necessary to set the length of the expanded guard field 528 to be equal to or 10 greater than 15 data bytes. The succeeding VFO area 522 sufficiently takes 71 data bytes. Thus, even if an overlap area of the expanded guard field 528 and the VFO area 522 slightly widens, there is no obstacle at the time of signal reproduction (because a time for 15 obtaining synchronization of reproduction reference clocks is sufficiently arranged in the VFO area 522 which does not overlap). Therefore, it is possible to set the value of the expanded guard field 528 to be greater than 15 data bytes. As has already been 20 described, a wobble strip rarely occurs at the time of continuous recording, and a recording position may be shifted by one wobble cycle. One wobble cycle corresponds to 7.75 (=?8) data bytes, and thus, in the present embodiment, a length of the expanded guard 25 field 528 is set to equal to or greater than 23 (= 15 + 8) data bytes. In the embodiment shown in FIG. 83 (c), like the buffer area 537, the length of the expanded guard field 528 is set to 24 data bytes in consideration of a margin of one data byte similarly. In FIG. 83 (e), it is necessary to precisely set the recording start position of the recording cluster 5 541. The information recording/reproducing apparatus according to the present embodiment detects this recording start position by using a wobble signal recorded in advance in the rewritable-type or writeonce type information storage medium. As shown in 10 FIGS. 78A to 78D, in all areas other than the wobble sync area 580, a pattern changes from NPW to IPW in units of four wobbles. In comparison, in the wobble sync area 580, wobble switching units are partially shifted from four wobbles, and thus, the wobble sync 15 area 580 can detect a position most easily. Thus, the information recording/reproducing apparatus according to the present embodiment detects a position of the wobble sync area 580, and then, carries out preparation for a recording process, and starts recording. Thus, 20 it is necessary to arrange a start position of a recording cluster 541 in a non-modulation area 590 immediately after the wobble sync area 580. FIG. 84 shows the contents of the allocation. The wobble sync area 580 is arranged immediately after switching 25 position of a physical segment. The length of the wobble sync area 580 is defined by 16 wobble cycles. Further, after detecting the wobble sync area 580, eight wobble cycles are required for preparation for the recording process in consideration of a margin. Therefore, as shown in FIG. 84, even in consideration of a ransom shift, it is necessary that the start 5 position of the VFO area 522 which exists at the start position of the recording cluster 541 is arranged rearwardly by 24 wobbles or more from a switching position of a physical segment. As shown in FIG. 83, a recording process is 10 carried out many times in a duplicate site 591 at the time of rewriting. When rewriting is repeated, a physical shape of a wobble groove or a wobble land changes (is degraded), and the wobble reproduction signal amount is lowered. In the present embodiment, 15 as shown in FIG. 83 (f), a contrivance is made so that a duplicate site 591 at the rewriting or at the time of additional writing is recorded in the non-modulation area 590 instead of arriving in the wobble sync area 580 or wobble address area 586. In the non-modulation 20 area 590, a predetermined wobble pattern (NPW) is merely repeated. Thus, even if a wobble reproduction signal amount is partially degraded, interpolation can be carried out by utilizing the preceding and succeeding wobble reproduction signals. In this way, 25 the position of the duplicate site 591 at the rewriting or at the time of additional writing has been set so as to be included in the non-modulation area 590. Thus, there occurs advantageous effect that a stable wobble detection signal from the wobble address information 610 can be guaranteed while preventing degradation of the wobble reproduction signal amount due to the shape 5 degradation in the wobble sync area 580 or wobble address area 586. Now, FIG. 85 shows an embodiment of a method for additionally writing a write-once type data recorded on a write-once type information storage medium. A 10 position rearwardly of 24 wobbles is defined as a writing start point from the boundary position of physical segment blocks. With respect to data to be newly additionally written, after a VFO area for 71 data bytes has been formed, a data area (data field) 15 in an ECC block is recorded. This writing start point coincides with an end position of the buffer area 537 of recording data recorded immediately before the writing. The backward position at which the expanded guard field 528 has been formed by a length for eight 20 data bytes is obtained as a recording end position of additional writing data (writing end point). Therefore, in the case where data has been additionally written, the data for eight data bytes is recorded to be duplicated at a portion of expanded guard field 529 25 recorded just before and the VFO area to be newly additionally written. Chapter 8: Description of B Format Optical disk specification of B format FIG. 86 shows specification of an optical disk in a B format using a blue violet laser light source. The 5 optical disks in the B format are classified into rewritable-type (RE disk), read-only (ROM disk), and write-once type (R disk). However, as shown in FIG. 86, common specification other than standard data transfer speed is defined in any type, facilitating the 10 achievement of a drive commonly compatible with a different type. In a current DVD, two disk substrates having thickness of 0.6 nm are adhered to each other. In contrast, a structure is provided such that, in the B format, a recording layer is provided on a disk 15 substrate having disk thickness of 1.1 nm, and the recording layer is covered with a transparent cover layer having thickness of 0.1 nm. [Error correction system] In the B format, there is employed an error 20 correction system capable of efficiently sensing a burst error referred to as a "picket" code. A "picket" is inserted into main data (user data) patterns at predetermined intervals. The main data is protected by strong, efficient Reed Solomon codes. A "picket" is 25 protected by second very strong, efficient Reed Solomon codes other than the main data. During decoding, a picket is first subjected to error correction. Correction information can be used to estimate a position of a burst error in the main data. As a symbol of these positions, there is set a flag called "erasure" utilized when correcting a code word of the 5 main data. FIG. 87 shows a configuration of a "picket" code (error correction block). An error correction block (ECC block) of the B format is configured while the user data of 64 Kbytes is defined in unit in the same 10 manner as in the H format. This data is protected by very string, Reed Solomon codes LDC (long distance codes). An LCD is formed of 304 cord words. Each code word is formed of 216 information symbols and 32 parity 15 symbols. Namely, a code word length has 248 (= 216 + 32) symbols. These code words are interleaved on a 2 x 2 basis in a vertical direction of ECC blocks, configuring an ECC block of horizontal 152 (= 304/2) bytes x vertical 496 (= 2 x 216 + 2 x 32) bytes. 20 A picket interleave length has 155 x 8 bytes (there are eight correction series of control codes in 496 bytes), and a user data interleave length has 155 x 2 bytes. The 496 types in the vertical direction are defined in units of recording on a 31 x 31 row basis. 25 With respect to the parity symbols of the main data, two-groove parity symbols are provided as nests on a one by one row basis. In the B format, picket codes padded at predetermined intervals have been employed for this ECC block in a "columnar" shape. A burst error is sensed by referring to a state of that error. Specifically, 5 four picket columns have been arranged at equal intervals in one ECC block. An address is also included in a "picket". A "picket" includes its unique parity. There is a need for correcting symbols in the 10 picket columns, and thus, the "pickets" in the right three columns are subjected to error correction and encoding by means of BIS (burst indicator subcode), and is protected. This BIS is formed of 30 information symbols and 32 parity symbols, and a code word length 15 has 62 symbols. It is found that very strong correction capability exists from a ratio between information symbols and parity symbols. The BIS code word is interleaved and stored in three picket columns each composed of 496 bytes. Here, 20 the number of parity symbols per code word which both of LDS and BIS codes have is equal to 32 symbols. This denotes that LDC and BIS can be decoded by one common Reed Solomon decoder. When data is decoded, first, a correcting process 25 of picket columns is carried out by means of the BIS. In this manner, a burst error location is estimated, and a flag called "erasure" is set in that location. This flag is utilized when a code word of the main data is corrected. The information symbols protected by the BIS codes forms additional data channels (side channels) other 5 than the main data. This side channel stores address information. Prepared executive Reed Solomon codes other than the main data are used for error correction of address information. This code is formed of five information symbols and four parity symbols. In this 10 manner, it has been possible to grasp an address at a high speed and with a high reliability independent of an error correction system of the main data. [Address format] In an RE disk, like a CD-R disk, a very thin 15 groove is engraved as a recording track like a spiral. A recording mark is written into a protrusive portion viewed in a laser light beam incident direction from among the irregularities (on-groove recording). Address information indicating an absolute 20 position on a disk is padded by slightly wobbling (meandering or swinging) this groove like a CD-R disk or the like. Digital data for modulating signal is included, the digital data indicating "1" or "0" in the shape or cycle of wobbling. FIG. 88 shows a wobble 25 system. A wobbling amplitude is slightly + 10 nm in a disk radial direction. 56 wobbles (about 0.3 mm in disk length) is obtained as one bit of address information = ADIP unit (described later). In order to write a fine recording mark without almost any displacement, it is necessary to generate a stable, precise recording clock signal. Therefore, 5 attention has been paid to a system in which a main frequency component of the wobbles is single and a groove is smoothly continuous. If the frequency is single, a stable recording clock signal can be easily generated from a wobble component sampled by a filter. 10 Timing information or address information is added to a wobble on the basis of this single frequency. "Modulation" is performed for the purpose of this addition. For this modulation system, a system in which an error is unlikely to occur is selected even if 15 a variety of variations specific to an optical disk occur. The following four variations of wobble signals generated in an optical disk are summarized on a factor by factor basis: 20 1) Disk noise: A variation in a surface shape which occurs with a groove portion (surface roughness) at the time of manufacturing, noise generated in a recording film, and crosstalk noise leaks from recorded data: 25 2) Wobble shift: A phenomenon that detection sensitivity is lowered by a relative shift of a wobble detection position from a normal position in a recording/reproducing apparatus. This shift is likely to occur immediately after seek operation. 3) Wobble beat: A crosstalk generated between a track to be recorded and a wobble signal of the 5 adjacent track. In the case where the rotation control system is CLV (constant linear velocity), this beating occurs in the case where a shift occurs with an angle frequency of the adjacent wobbles. 4) Defect: This is caused by a local defect due to 10 the dust or scratch of a disk surface. In an RE disk, two different wobble modulation systems are combined in the form such that a synergetic effect is produced under a condition that high durability is provided with respect to all of these 15 different four types of signal variations. In general, this is because the durability relevant to four types of signal variations which is hardly achieved by only one type of modulation system can be obtained without any side effect. 20 There are two systems: an MSK (minimum shift keying system; and an STW (saw tooth wobble) system (FIG. 89). The name of the STW comes from the fact that its waveform is like a saw tooth shape. In the RE disk, one bit of "0" or "1" is expressed 25 by a total of 56 wobbles. These 56 wobbles are referred to as a unit, i.e., an ADIP (address inpre groove) unit. When the ADIP unit is continuously read out by 83 units, an ADIP word indicating one address is obtained. The ADIP word is formed of: address information having a 24-bit length; auxiliary data having a 12-bit length; a reference (correction) area; 5 and error correction data. In the RE disk, three ADIP words per one RUB (recording unit block, units of 64 Kbytes) for recording main data have been arranged. The DIP unit consisting of 56 wobbles is greatly divided into a first half and a latter half. The first 10 half whose wobble numbers range from 0 to 17 is an MSK system; and the latter half whose wobble numbers range from 18 to 55 is a STW system. These systems smoothly communicate with a next ADIP unit. One bit can be expressed by one ADIP unit. Depending on whether "0" 15 or "1" is set, first, in the first half, there is changed a position of a wobble to which MSK system modulation is applied; and, in the latter half, an orientation of a saw tooth shape is changed, thereby making discrimination. 20 The first-half portion of the MSK system is divided into: a three-wobble area in which MSK modulation has been further performed; and a mono-tone wobble cos (cot) area. First, three wobbles from 0 to 2 always start from at any ADIP unit to which MSK 25 modulation has been applied. This is referred to as a bit sync (identifier indicating start position of ADIP unit). After this identifier has been passed, continuation of mono-tone wobbles is then obtained. Then, data is indicated according to how many mono-tone wobbles exist up to three wobbles which appear again 5 next and which has been subjected to MSK modulation. Specifically, "0" is set in the case of 11 wobbles, and "1" is set in the case of 9 wobbles. Data is discriminated from each other by means of a shift of two wobbles. The MSK system utilizes a local phase 10 change of a basic wave. In other words, an area in which no phase change occurs is dominant. In the STW system as well, this area is efficiently utilized as a location in which a phase of a basic wave does not change. 15 An area to which MSK modulation has been applied has a three-wobble length. A phase is restored by setting a frequency at 1.5 times with respect to a mono-tone wobble at the first wobble; setting a frequency equal to that of a mono-tone wobble at the 20 second wobble; and setting a frequency at 1.5 times again at the third wobble. By doing this, the polarity of the second (center) wobble is just inverted with respect to the mono-tone wobble, and this inversion is detected. At the first start point and at the third 25 end point, a phase is just fitted to a mono-tone wobble. Therefore, smooth connection free from a discontinuous portion can be made. On the other hand, there are two types of waveforms in the latter half STW system. One waveform rapidly rises toward the disk outer periphery side and returns in gentle inclination to the disk center side, 5 and the other waveform rises in gentle inclination, and returns rapidly. The former indicates data "0", and the latter indicates data "1". In one ADIP unit, the same bit is indicated by using both of the MSK system and the STW system, thereby improving data reliability. 10 When the STW system is mathematically expressed, a secondary harmonic wave sin (2cot) whose amplitude is 1/4 is added to or subtracted from a basic wave cos (cot) . However, even whichever of "0" and "1" the STW system indicates, a zero cross point is identical to a 15 mono-tone wobble. Namely, its phase is not affected at all when a clock signal is sampled from a basic wave component common to a mono-tone portion in the MSK system. As described above, the MSK system and the STW 20 system function so as to compensate for weak points of counterparts each other. FIG. 90 shows an ADIP unit. A basic unit of an address wobble forma is an ADIP unit. Each group of 56 NML (nominal wobble length) is referred to as an 25 ADIP unit. One NML is equal to 69 channel bits. An ADIP unit of a different type is defined by inserting a modulation wobble (MSK mark) into a specific position contained in an ADIP unit (refer to FIG. 89). 83 ADIP units are defined as one ADIP word. A minimum segment of data recorded in a disk precisely coincides with three continuous ADIP words. Each ADIP word includes 5 36 information bits (24 bits of which are address information bits). FIGS. 91 and 92 each show a configuration of an ADIP word. One ADIP word includes 15 nibbles, and nine 10 nibbles are information nibbles, as shown in FIG. 93. Other nibbles are used for ADIP error correction. 15 nibbles configure a code word of Reed Solomon codes [15, 9, 7] . A code word is formed of nine information nibbles; 15 six information nibbles record address information; and three information nibbles record auxiliary information (for example, disk information). Reed Solomon codes of [15, 9, 7] are nonsystematic, and a hamming distance due to "informed 20 decoding" in knowledge in advance can be increased. The "informed decoding" is such that all code words have distance 7; all cod words of nibble ng has distance 8 in common; and knowledge in advance relating to ng increases a hamming distance. Nibble ng is 25 formed of an MSB of a layer index (three bits) and a physical sector number. If nibble ng is known, distance increases from 7 to 8. FIG. 94 shows a track structure. A description will be given here with respect to a track structure of the first layer (which is distant from a laser light source) and the second layer of a disk having a single- 5 sided double-layer structure. A groove is provided to enable tracking in a push-pull system. Plural types of track shapes are used. The first layer LQ and the second layer L]_ are different from each other in tracking direction. In the first layer, the left to 10 the right of the figure is a tracking direction. In the second layer, the right to the left is a tracking direction. The left side of the figure is a disk inner periphery, and the right side is an outer periphery. A BCA (burst cutting area) area formed of a first- 15 layer straight groove; a pre-recording area formed of an HFM (High Frequency Modulated) groove; and a wobble groove area in a rewritable area are equivalent to an H-format lead-in area. A wobble groove area in a second-layer rewritable area; a pre-recording area 20 formed of an HFM (High Frequency Modulated) groove; and a BCA area formed of a straight groove are equivalent to an H format lead-out area. However, in the H format, the lead-in area and the lead-out area are recorded in a pre-pit system instead of a groove 25 system. In the HFM groove, a phase is shifted in the first and second layers so as not to produce an interlayer crosstalk. FIG. 95 shows a recording frame. As shown in FIG. 87, the user data is recorded on 64 by 64 Kbytes basis. Each row of the ECC cluster is converted into the recording frame by adding frame sync bits and DC 5 control units. The stream of 1240 bits (155 bytes) in each row is converted as follows. Data of 25 bits is arranged at the beginning of the 1240-bit stream, and the subsequent data is divided into data of 45 bits; a frame sync code of 20 bits is added before data of 10 25 bits; one DC control bit is added after data of 25 bits; and one DC control bit is added after data of 45 bits similarly. A block including data of the first 2 bits is defined as DC control block #0, and the subsequent data of 45 bits and one DC control bit are 15 defined as DC control blocks #1, #2, ... #27. 496 recording frames are referred to as a physical cluster. A recording frame is subjected to 1-7PP modulation at a rate of 2/3. A modulation rule is applied to 1268 bits excluding the first frame sync code; 1902 channel 20 bits are formed; and a frame sync code of 30 bits is added at the beginning of the entirety. That is, 1932 channel bits (= 28 NML) are configured. A channel bit is subjected to NRZI modulation, and the modulated bit is recorded in a disk. 25 Frame sync code structure Each physical cluster includes 16 address units. Each address unit includes 31 recording frames. Each recording frame starts from a frame sync code of 30 channel bits. The first 24 bits of frame sync code violates a 1-7PP modulation rule (including a length which is twice of 91). Ihe 1-7PP modulation rule uses 5 a (1, 7)PLL modulation system to carry out Parity Preserve/Prohibit RMTR (repeated minimum transition run length). Parity Preserve makes control of a so called DC (direct current) component of a code (decreases a DC component of a code). The remaining six bits of frame 10 sync code changes, and identifies seven frame sync codes FSO, FS1, ... FS6. These six-bit signs are selected so that a distance relating to a deflection amount is equal to or greater than 2. Seven frame sync codes make it possible to obtain 15 more detailed positional information than only 16 address units. Of course, it is insufficient to identify 31 recording frames merely by seven different frame sync codes. Therefore, from 31 recording frames, seven frame sync sequences are selected so that each 20 frame can be identified by using a combination between one's own frame sync codes and a frame sync code of each of four preceding frames. FIGS. 96A and 96B each show a structure of a recording unit block RUB. A recording unit is referred 25 to as a RUB. As shown in FIG. 96A, the RUB is formed of: 40-wobble data run-in; a physical cluster of 496 x 28 wobbles; and 16-wobble data run-out. Data run-in and data run-out enables sufficient data buffering in order to facilitate completely random overwriting. The RUB may be recorded on a one by one basis or a plurality of RUBs are continuously recorded as shown in 5 FIG. 96B. Data run-in is mainly formed of a repetition pattern of 3T/3T/2T/2T/5T/5T, and two frame sync codes (FS4 and FS6) are spaced from each other by 40cbs as an indicator indicating a start position of a next 10 recording unit block. The data run-out starts at FSO, follows a 9T/9T/9T/9T/9T/9T pattern which indicates the end of data after FSO, and follows a repetition pattern mainly formed of 3T/3T/2T/2T/5T/5T. 15 FIG. 97 shows a structure of data run-in and data run-out. FIG. 98 is a view showing allocation of data relating to a wobble address. A physical cluster is formed of 496 frames. A total of 56 wobbles (NWLs) of 20 data run-in and data run-out are 2 x 28 wobbles, and correspond to two recording frames. One RUB = 496 + 2 = 498 recording frames One ADIP unit = 56 NWLs = Two recording frames 83 ADIP units = One ADIP word (including one ADIP 25 address) Three ADIP words = 3 x 83 ADIP units Three ADIP words = 3 x 83 x 2 = 498 recording frames When data is recorded in a write-once disk, it is necessary to continuously record next data in already 5 recorded data. If a gap occurs with data, reproduction cannot be carried out. Then, in order to record (overwrite) the first data run-in of the succeeding recording frame to be overlapped on the last data runout of the preceding recording frame, three guard areas 10 are arranged at the end of the data run-out area, as shown in FIGS. 99A and 99B. FIG. 99A shows a case in which only one physical cluster is recorded; and FIG. 99B shows a case in which a plurality of physical clusters are continuously recorded, wherein three guard 15 areas are provided only after run-out of the last cluster. Thus, each of the recording units recorded along, or alternatively, a plurality of recording unit blocks continuously recorded are terminated in three guard areas. These three guard areas guarantees that 20 an unrecorded area does not exist between the two recording unit blocks. Now, a description will be given with respect to reproduction durability of a write-once type information storage medium according to an embodiment 25 of the present invention. This storage medium includes a transparent resin substrate formed in a disk shape, the substrate being made of a synthetic resin material such as polycarbonate, for example. On this transparent resin substrate, a groove is formed in a concentric shape or in a spiral shape. This transparent resin substrate can be manufactured by 5 injection molding using a stamper. In addition, on this transparent resin substrate, a recording film including an organic dye is formed so as to fill its groove. An organic dye forming this recording film is used such that its maximum absorption 10 wavelength area is shifted to a longer wavelength side than a recording wavelength (405 nm). In addition, absorption is not eliminated in a recording wavelength area, and a design has been made so as to have substantial light absorption. 15 In this manner, in the case where focusing or tracking is carried out on a track before information recording by means of a recording laser light beam, a low light reflectivity is obtained. A dye decomposing reaction is caused by the laser light beam, and the 20 light absorbance is lowered, and thereby the light reflectivity of a recording mark portion rises. Thus, there are achieved so called a low-to-high (L to H) characteristic that the light reflectivity of the recording mark portion formed by irradiating the laser 25 light beam is higher than that before the laser light irradiation. In addition, a transparent resin substrate, and, in particular, a groove bottom may be deformed due to a heat generated. In this case, a phase difference may occur with reflection light. The above-described organic dye is liquefied by 5 being solved in a solvent, and the liquefied dye can be easily applied onto a transparent resin substrate surface in accordance with a spin coat technique. In this case, film thickness can be managed with high precision by controlling a dilution rate based on a 10 solvent or a rotation speed at the time of spin coating. The organic dye consists of a dye portion and an counter-ion (anion) portion. As the dye portion, a cyanine dye or a styryl dye and the like can be used. 15 In particular, the cyanine dye and the styryl dye are preferred because absorbance relative to a recording wavelength is easily controlled. Referring to FIGS. 102A to 102E and 101A to 101C, a description will be given with respect to a method 20 for producing a disk stamper for a write-once type storage medium. As shown in FIG. 102A, there is prepared: a silicon wafer 2011 for manufacturing a semiconductor, the wafer being formed in a disk shape to have a 25 diameter of 200 nm and thickness of 0.725 mm. This silicon wafer 2011 is immersed for 5 minutes in a mixture solution of a thermal concentrated sulfuric acid and hydrogen peroxide water (solution temperature 100°C). Next, the silicon wafer 2011 is rinsed by immersing it in ultra-pure water, and the rinsed wafer is washed with ultrasound waves; the 5 washed wafer is immersed in a 70°C ultra-pure water tank, and the immersed wafer is dried by gradually pulling it up. Then, as shown in FIG. 102B, an electron beam resist film 2012 is formed on a surface of the silicon 10 wafer 2011. This electron beam resist film 2012 is formed by spin-coating a resist solution obtained by mixing and stirring an electron beam resist (ZEP520A7 available from ZEON Corporation) by 86.2% by weight with respect to an anisole solvent (ZEP-A available 15 from ZEON Corporation) on a surface of the silicon wafer 2011. In addition, in a spin coating condition, the silicon wafer 2011 is vacuum-chucked on a spin table; a resist solution is dropped at the center part of the 20 silicon wafer 2011 via a 0.1 micron filter while rotation of the spin table stops; and then, the spin table is rotated at 2500 rpm. Then, as shown in FIG. 102C, a groove 2013 is formed in the electron beam resist film 2012. This is 25 accomplished by putting the silicon wafer 2011 coated with the electron beam resist film 2012 in a vacuum tank serving as an electron beam cutting machine; carrying out evacuation up to 10~5 Pa; and then, rotating the silicon wafer 2011; irradiating an electron beam from an electron gun 2014 to the electron beam resist film 2012; and carrying out electron-beam 5 recording of a concentric or spiral groove pattern. A groove pattern recording condition is such that an electron beam acceleration voltage is 50 kV; a beam current is 120 nA; a beam diameter is 110 nm; and a recording beam linear speed is 1.1 m/sec. In a 10 recording area of the groove 2013, the radius of the silicon wafer 2011 ranges from 23 mm to 59 mm. Then, the silicon wafer 2011 on which the groove 13 has been recorded is removed from the inside of the vacuum tank serving as the electron beam cutting 15 machine, and dip developing is carried out while the removed silicon wafer is immersed in an organic developing solution 2016 contained in an immersing tank 2015, as shown in FIG. 102D, thereby forming a resist pattern of the groove 2013. 20 Next, DC sputtering of an Ni film is carried out, and thereby an Ni thin film 2017 is formed and electrically conducted onto the above-described resist pattern surface, as shown in FIG. 102E. Then, as shown in FIG. 101A, Ni electric casting 25 is carried out on the Ni thin film 2017, forming an Niplated layer 2018 having thickness of 247 Then, as shown in FIG. 101B, the Ni-plated layer 2018 is released, and spin-coated, and then, the residual resin is released from a surface by means of oxygen RIE. Then, as shown in FIG. 101C, the Ni-plated layer 2018 is coated with a protective film; a back face side 5 thereof is polished; an inner diameter and an outer diameter are processed; and a disk stamper 2019 is produced. Next, a write-once type optical disk is produced by using this disk stamper 2019. That is, as shown in 10 FIG. 100A, by using the disk stamper 2019, injection molding is carried out by using an injection molding device SD40 available from Sumitomo Heavy Industries Co., Ltd, thereby duplicating a transparent disk substrate 2020 made of polycarbonate having thickness 15 of 0.6 mm as shown in FIG. 101B. A groove 2021 is, of course, formed on this disk substrate 2020. Then, as shown in FIG. 100C, by using a dispenser 2022 having a nozzle diameter of 21G, an organic dye solution 2023 described later obtained by dissolving an 20 organic dye in a solvent is dropped on a surface of the disk substrate 2020 on which the groove 2021 is formed. Next, by rotationally controlling the disk substrate 2020, as shown in FIG. 100D, the groove 2021 is filled with the organic dye solution 2023, and a recording 25 film 2024 is formed. A spin coat condition of this recording film 2024, as shown in FIG. 103, is such that, first, the disk substrate 2020 is rotationally driven from an inactive state to 300 rpm within 1 second, and the organic dye solution 2023 is coated by means of the dispenser 2022 while this state is maintained for 8 seconds. Next, 5 the rotation frequency of the disk substrate 2020 is increased to 1800 rpm within 2 seconds, and this state is maintained for 15 seconds. Then, the rotation frequency of the disk substrate 2020 is increased to 3000 rpm within 2 seconds, and this state is maintained 10 for 3 seconds. The film thickness of the recording film 2024 can be controlled by controlling the rotation speed at a second stage. More specifically, the film thickness of the recording film 2024 can be increased by setting the 15 rotation speed at the second stage at a low speed. Next, the disk substrate 2020 coated with the recording film 2024 is baked at 80°C for 30 seconds by using a clean oven, and a 100 nm metal film 2025 is sputtered on the recording film 2024, as shown in 20 FIG. 100E. An Ag alloy including 1% of Bi in Ag is used as this metal film 2025. Then, as shown in FIG. 100F, an ultraviolet-ray curing type resin 2026 is spin-coated on the metal film 2025, and a disk substrate 2027 made of polycarbonate 25 having thickness of 0.6 mm is adhered onto the spincoated resin, and thereby a write-once type optical disk (R disk) 2028 including an organic dye in the recording film 2024 is produced. Here, in the write-once type optical disk 2028 produced as described above, a laser light beam for recording and reproduction by an optical head 2029 is 5 made incident from a face opposite to a face coated with the recording film 2024 of the disk substrate 2020, as shown in FIG. 104. In this case, a bottom face 2021a of the groove 2021 formed on the disk substrate 2020 and a land 2020 10 sandwiched between the adjacent grooves 2021 are obtained as information recording tracks. The recording track made of the bottom face 2021a of the groove 2021 is referred to as a groove track Gt, and the recording track made of the land 2030 is referred 15 to as a land track Lt. In addition, a height difference between a face of the groove track Gt and a face of the land track Lt is referred to as a groove depth Gh. Further, a width of the groove track Gt viewed from a height which is 20 almost 1/2 of the groove depth Gh is referred to as a groove width Gw, and a width of the land track Lt viewed from a height which is almost 1/2 of the groove depth Gh is referred to as a land width Lw. Now, a description will be given with respect to 25 generation of the above-described organic dye solution 2023. This organic dye solution 2023 is used as a solution having a solution concentration of 1.2% by weight obtained by dissolving organic dye powders of 1.2g in 100 nm of TFP. A solution condition for a solvent is such that dye powders are put in the solvent, and ultrasound waves are applied for 5 30 minutes. By using the organic dye, a write-once optical disk 2028 is produced by the above-described method, and recording and reproduction are carried out in these groove tracks Gt, thereby carrying out an evaluation 10 test. As an evaluation device, an optical disk evaluation device available from PULSTEC Co., Ltd is used. A testing condition is such that an objective lens aperture NA of an optical head is 0.65; a wavelength of 15 a laser light beam for recording and reproduction is 405 nm; and a linear velocity during recording and reproduction is 6.61 m/sec. A recording signal is 8-12 modulated random data, and is a waveform recorded by predetermined recording power and two types of bias 20 powers 1 and 2 as shown in FIG. 105. In addition, track pitches are 400 nm; a groove width Gw is defied as "1.2" with respect to a land width Lw "I"; a wobble amplitude of the groove track Gt is 14 nm; and the groove depth Gh is 60 nm. Wobble 25 phase modulation is used to record address information using wobbles. Here, three types of evaluation characteristics are measured including: a carrier noise ratio CNR of a reproduction signal; an SN ratio during partial response (partial response signal to noise ratio: PRSNR); and a simulated bit error rate SbER. PRSNR 5 defining and measuring techniques are described in a book which can be purchased from DVD Format Logo Licensing Co., Ltd. This is a part of Annex H of DVD Specifications for High Density Read-Only Disc PART 1 Physical Specifications Version 1.0. It is preferable 10 that the PRSNR be 15 or more. The SbER defining and measuring techniques are described in a book which can be purchased from DVD Format Logo Licensing Co., Ltd. This is a part of Annex H of DVD Specifications for High Density Read-Only Disc PART 1 Physical 15 Specifications Version 1.0. It is preferable that the SbER be 5.0 x 10~5 or less. The PRSNR and SbER are measured in a state in which information is recorded in the adjacent tracks. As evaluation characteristics, three types of 20 light reflectivity, SbER, and PRSNR are measured. A light reflectivity defining and measuring techniques are described in a book which can be purchases from DVD Format Logo Licensing Co., Ltd. This is a part of Annex D of DVD Specifications for High Density Read- 25 Only Disc PART 1 Physical Specifications Version 1.0. The reflectivity corresponds to I11H level after recording. It is preferable that the reflectivity range from 14% to 28% in order to obtain reproduction light durability of 1,000,000 times or more. In addition, in the case where management information (system lead-in) is inserted into a certain 5 portion of a disk, for example, into the innermost peripheral area, the most advantageous effect can be attained in this Low-to-High recording disk. With respect to management information, pit arrays identical to those on a ROM disk substrate are formed on a disk 10 substrate. What is recorded as a pit array is management information such as whether the disk is a read-only type or write-once type, or rewritable type; what recording and reproducing wavelength is, whether the recording film type is Low-to-High or High-to-Low, 15 and what a recording data capacity is. The track pitches of a groove of a recording data area are selected as 400 nm or in the range of 320 nm to 300 nm. Advantageously, the track pitches of the pit array in this management information area is formed to be wider 20 than the above track pitches, and data bit pitches of pits are larger than that of the recording data area, thereby facilitating reproduction and making it possible to easily judge management information. The Low-to-High disk is uniform in signal level position 25 between a system lead-in area and a data area, and drive reproduction is made easy. Now, a description will be given with respect to a test result relating to reproduction durability count in the case where a mark recorded in an optical disk using an organic dye material according to the present invention for a recording material has been 5 continuously reproduced by a blue laser light beam pickup. Here, testing has been carried out with respect to 5 types of organic dye materials. A first material is dye "A" which is an organic metal complex simplex, and a general structural formula 10 of Al which is an example of the dye is shown in FIG. 106. Cu, Zn, Ni, Co, Fe, Sc, Ti, V, Cr, Mn, Al, Gd, and Y or the like are mainly used as M. Cu is the best in reproduction light durability. As Rl to R5, there are used CH3, C2H5, H, 15 CH2N(CH3)2, SCH3, N02, Cl, S02NHCH3, CN, and CH30CH2 or the like without being limited thereto. In particular, in the case where Cl has been added, the best reproduction light durability is obtained. In an example Al of dye "A", M is Cu; Rl is CH3; 20 R2 is CH3; R3 is Cti^; R4 is Cl; and R5 is Cl. A second material is dye B which is an organic metal complex simplex having another structure, and a general structural formula of Bl which is an example of the dye is shown in FIG. 107. Cu, Zn, Ni, Co, Fe, Sc, 25 Ti, V, Cr, Mn, Al, Gd, and Y or the like are mainly used as M. Cu is the best in reproduction light durability. As Rl to R5, there are used CH3, C2H5, H, CH2N (CH3) 2i SCH3, N02, Cl, S02NHCH3, CN, and CH3OCH2 or the like without being limited thereto. In particular, in the case where Cl has been added, the best 5 reproduction light durability is obtained. In an example Bl of dye B, M is Cu; Rl is C2H5; R2 is CH3; R3 is C2H5,- R4 is SCH3; and R5 is Cl. Bl is better than Al in PRSNR and SbER when it is used for an optical disk; and is better in recording 10 and reproducing characteristics such as large degree of modulation and high reflectivity. A third dye is a mixture dye made of an organic metal complex cation and anion U composed of cation and an organic metal complex anion; an organic metal 15 complex cation and anion W composed of cation and an organic metal complex anion; and an organic metal complex simplex Y, and is a mixture of dye Ul, dye Wl, and dye Y2. An azo phthalocyanine metal complex has been used as Y. A general structural formula of U, a 20 general structural formula of W, and a general structural formula of Y are shown in FIG. 108, FIG. 109, and FIG. 110, respectively. Here, a cation portion in FIG. 108 is a monomethine cyanine dye, and an anion portion in 25 FIG. 108 is an organic metal complex. In addition, with respect to the above-described monomethine cyanine dye, Z]_ and Z2 represent aromatic rings which are identical to or different from each other, and these aromatic rings may have substituents. Y]_]_ and Y]_2 each represent a carbon atom or a hetero atom independently. R]_]_ and R]_2 each represent an 5 aliphatic hydrocarbon group, and these aliphatic hydrocarbon groups may have substituents. RIS? ^14? R]_5, and R]_g each represent a hydrogen atom or an appropriate substituent independently. In the case where ¥]_]_ and Y]_2 are hetero atoms, part or all of R]_3, 10 R14' R15' and Ri6 do/does not exist. In addition, in the above-described organic metal complex, A and A1 represent heterocyclic groups which are identical to or different from each other, the groups each containing one or a plurality of hetero 15 atoms selected from a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom. R2i to R24 each represent a hydrogen atom or a substituent independently. ¥21 and ¥22 each represent hetero atoms which are identical to or different from 20 each other, the atoms each being selected from elements of a sixteenth family in the periodic table. Monomethine cyanine dyes used in the present embodiment can include dyes obtained when cyclic nucleuses such as an imidazoline ring; an imidazole 25 ring; a benzoimidazole ring; an a-naphthoimidazole ring; a p-naphthoimidazole ring; an indole ring; an isoindole ring; an indorenin ring; an isoindorenin ring; a benzo indorenin ring; a pyridino indorenin ring; an oxazolline ring; an ozazole ring; an isoozazole ring; a benzooxazole ring; pyridino oxazole ring; an a-naphtooxazole ring; a p-naphthoozazole ring; 5 a serenazoline ring; a serenazole ring; a benzoserenazole ring; an a-naphthoserenazole resin; a p-naphthoserenazole ring; a thiazoline ring; a thiazole ring; an isothiazole ring; a benzothiazole ring; an xnaphthothiazole ring; a p-naphthothiazole ring; a 10 terrazoline ring; a terrazole resin; a benzoterrazole ring; an a-naphthoterrazole ring; a p-naphthoterrazole ring; and further, an acrydine ring; an antracen ring; an isoquinoline ring; an isopyrole ring; an imidanoxaline ring; an indandione ring; an indazole 15 ring; an indaline ring; an oxadiazole ring; a carbazole ring: a xantene ring; a quinazoline ring; a quinoxaline ring; a quinoline ring; a chroman ring; a cyclohexane dione ring; a cyclopentane dione ring; a cinnoline ring; a thiodiazole ring; a thiooxazolidone ring; a 20 thiophene ring; a thionaphthene ring; a thiobarbizuric acid ring; a thiohidantoin ring; a tetrazole resin; a triazine ring; a naphthalene ring; a naphthyridine ring; a piperadine ring; a pyradine ring; a pyrazole ring; a pyrazoline ring; a pyrazolidine ring; a 25 pyrazolone ring; a pyrane ring; a pyridine ring; a pyridazine ring; a pyrimidine ring; a pyrilium ring; a pyrolidine ring; a pyroline ring; a pyrol ring; a phenedine ring; a phenantholidine ring; a phenanthorene ring; a phenanthoroline ring; a phthaladine ring; a putheridine ring; a phrazane ring; a phrane ring; a purine ring; a benzene ring: a benzooxadine ring; a 5 benzopirane ring; a morpholine ring; and a rhodaline ring or the like, which are identical to or different from each other, having one or a plurality of substituents, are bonded on both ends of a monomethine chain which may have one or a plurality of 10 substituents. In addition, through general formulas of the monomethine cyanine dye, Zl to Z3, for example, represent aromatic rings such as a benzene ring, a naphthalene ring, a pyridine ring, a quinoline ring; 15 and a quinoxaline ring or the like, and these aromatic rings may have one or a plurality of substituents. The substituents, for example, can include: aliphatic hydrocarbon groups such as a methyl group, a trifluoro methyl group, an ethyl group, a propyl group, an 20 isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a 1-methyl pentyl group, a 2-methyl pentyl group, a hexyl group, an isohexyl group, a 5-methyl 25 hexyl group, a heptyl group, and an octyl group; cycloaliphatic hydrocarbon groups such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group; aromatic hydrocarbon groups such as a phenyl group, a biphenyl group, an o-tryl group, an m-tryl group, a p-tryl group, a xyryl group, a mecityl group, an o-cumenyl group, an m-cumenyl group, a 5 p-cumenyl group; ether groups such as a methoxy group, a trfluoro methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a buthoxy group, a secbuthoxy group, a tert-buthoxy group, a pentyloxy group, a phenoxy group, a benzoir oxy group; ester groups such 10 as a methoxycarbonyl group, a trifluoro methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, an acetoxy group, and a benzoir oxy group; halogen groups such as a fluoro group, a chloro group, a bromo group, and an iodine group; thio groups such as 15 a metylthio group, an ethylthio group, propylthio group, butylthio group, and a phenylthio group; sulfurmoyl groups such as a methyl sulfurmoyl group, a dimethyl sulfurmoyl group, an ethyl sulfurmoyl, a diethyl sulfurmoyl group, a propyl sulfurmoyl group, a 20 dipropyl sulfurmoyl group, a butyl sulfurmoyl group, and a dibutyl sulfurmoyl group; amino groups such as a first class amino group, a methyl amino group, a dimethyl amino group, an ethyl amino group, a diethyl amino group, a propyl amino group, a dipropyl amino 25 group, an isopropyl amino group, a diisopropyl amino group, a butyl amino group, a dibutyl amino group, and a pyperidino group; carbamoyl groups such as a methyl carbamoyl group, a dimethyl carbamoyl group, an ethyl carbamoyl group, a diethyl carbamoyl group, a propyl carbamoyl group, and a dipropyl carbamoyl group; and further, a hydroxy group, a carboxy group, a cyano 5 group, a nitro group, a sulfino group, a sulfo group, and a mecyl group or the like. In a general formula, Z]_ and Z2 may be identical to or differential from each other. ¥]_]_ and Y]_2 in a general formula of a monomethine 10 cyanine dye each represent a carbon atom or a hetero atom. Hetero atoms, for example, can include atoms of a fifteenth family and a sixteenth family in the periodic table such as a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, or a tellurium atom. 15 The carbon atoms in ¥]_]_ and Y]_2 maY be an atom group consisting essentially of two carbon atoms such as an ethylene group and a vinylene group, for example. ¥]_]_ and Y]_2 in the general formula of the monomethine cyanine dye may be identical to or different from each 20 other. Rll' R12' and RIB in the general formula of the monomethine cyanine dye represent aliphatic hydrocarbon groups. Example of the aliphatic hydrocarbon groups can include: a methyl group; an ethyl group; a propyl 25 group; an isopropyl group; an isopropenyl group; a 1-propenyl group; a 2-propenyl group; a butyl group; an isobutyl group; a sec-butyl group; a tert-butyl group; a 2-butenyl group; a 1, 3-butadinyl group; a pentyl group; an isopentyl group; a neopentyl group; a tertpentenyl group; a 1-methyl pentyl group; a 2-methyl pentyl group; a 2-pentenyl group; a hexyl group; an 5 isohexyl group; a 5-methyl hexyl group; a heptyl group, and an octyl group or the like. The aliphatic hydrocarbon groups may have one or a plurality of substituents similar to those in Z]_ to Z. In addition, R]_1 and R]_2 in the general formula of 10 the monomethine cyanine dye may be identical to or different from each other. R]_3 to R]_g in the general formula of the monomethine cyanine dye each represent hydrogen atoms or proper substituents independently in individual 15 general formulas. The substituents, for example, include: aliphatic hydrocarbon groups such as a methyl group, a trifluoro methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, 20 a pentyl group, an isopentyl group, a neopentyl group; a tert-pentyl group, a 1-methyl pentyl group, a 2-methyl pentyl group, a hexyl group, an isohexyl group, a 5-methyl hexyl group, a heptyl group and a octyl group; ether groups such as a methoxy group, a 25 trifluoro methoxy group, an ethoxy group, a propoxy group, buthoxy group, a tert-buthoxy group, a pentyl oxy group, a phenoxy group, and a benxoir oxy group; halogen groups such as a fluoro group, a chloro group, a bromo group, and an iodine group; and further, a hydroxy group; a carboxy group; a cyano group; and a nitro group or the like. In the general formula of the 5 monomethine cyanine dye, in the case where ¥]_]_ and Y]_2 are hetero atoms, part or all of R]_3 to R]_g in Z]_ and Z2 do/does not exist. In addition, in the general formula of the abovedescribed azo metal complex, A and A1 each represent 10 heterocyclic groups of five rings to ten rings such as a furyl group, a thienyl group, a pyroryl group, a pyridyl group, a pypelidino group, a pypelizyl group, a quinoryl group, and an isooxazoryl group, for example, which are identical to or different from each other and 15 contain one or a plurality of hetero atoms selected from among a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom. These heterocyclic groups, for example, may have one or a plurality of aliphatic hydrocarbon groups such as a 20 methyl group, a trifluoro methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a 1-methyl pentyl group, a 25 2-methyl pentyl group, a hexyl group, an isohexyl group, and a 5-methyl hexyl group; ester groups such as a methoxy carbonyl group, a trifluoro methoxy carbonyl group, an ethoxy carbonyl group, a propoxy carbonyl group, an acetoxy group, a triflyoro acetoxy group, and benzoir oxy group; aromatic hydrocarbon groups such as a phenyl group, a biphenyl group, an o-tryl group, an 5 m-tryl group, a p-tryl group, an o-cumenyl group, an m-cumenyl group, a p-cumenyl group, a xyryl group, a mecityl group, a styryl group, a cinnamoyl group, and a naphtyl group; and further, substituents such as a carboxyl group, a hydroxy group, a cyano group, and a 10 nitro group. An azo compound configuring an azo-based organic metal complex represented by a general formula can be obtained in accordance with a normal technique by reacting a diazonium salt having R2l> ^22 or R23' R24 15 which corresponds to the general formula with heterocyclic compounds such as an isooxazolone compound, an oxazolone compound, a thionaphthene compound, a pyrazolone compound, a barbizuric acid compound, a hydantoin compound, and a rhodanine 20 compound or the like, for example, having an active methylene group adjacent to a carbonyl group in a molecule. ¥21 and ¥22 each represent hetero atoms which are identical to or different from each other, the atoms being selected from elements of the sixteenth 25 family in the periodic table such as an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom, for example. The azo metal complex represented by the general formula is generally used in a mode in which one or a plurality of metal complexes are oriented at a metal (center atom). Examples of metal elements serving as 5 the center atoms, for example, can include scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium, iron, lutenium, osmium, cobalt, rhodium, iridium, nickel, palladium, platinum, 10 copper, silver, gold, zinc, cadmium, and mercury or the like. In particular, cobalt is preferred. X^ in the general formula represents a proper anodic ion including an onium ion such as alkyl ammonium ion, a pyridinium ion, and quinolinium ion, for example. 15 As M of the azo phthalocyanine complex Y, there is used any of Cu, Ni, Al, Zn, Y, Co, Fe, Sc, Ti, V, Cr, and Mn. In particular, Cu is the best in reproduction light durability. As R, there is used CH3, C25 H CH2N(CH3)2' 20 SCH3, NC2, Cl, SC2NHCH3, CN, CH30CH2, and SC^H or the like without being limited thereto. In particular, in the case where Cl is added, the reproduction light durability is good. Structural formulas of Ul which is an example of 25 U, Wl which is an example of W, and Y2 are shown in FIG. Ill and FIG. 112. With respect to Y2 which is an example of Y, Ni is selected as M, and N02 is selected as R. A mixture ratio by weight of U, W, and Y is 1.0 : 2.0 : 0.15. If a formazane metal complex V is used instead of 5 Y2, a similar dye is obtained. A structural formula of V is shown in FIG. 113. A fourth dye is a mixture dye of an organic metal complex B; an organic metal complex cation and anion W composed of cation and an organic metal complex anion; 10 and an organic metal complex simplex Y, and is a mixture of dye Bl, dye W2, and dye Yl. An axo phthalocyanine metal complex was used as Y. A general structural formula of W2 which is an example of W is shown in FIG. 114. 15 In Yl which is an example of Y, Cu is selected as M, and Cl is selected as R. A mixture ratio by weight of B, W, and Y is 0.7 : 0.3 : 0.15. A fifth dye is a mixture dye of an organic metal 20 complex cation and anion U composed of cation and an organic metal complex anion; an organic metal complex cation and anion W composed of cation and an organic metal complex anion; and an organic metal complex simplex Y, and is a mixture of dye Ul, dye Wl, and dye 25 Y2. An azo phthalocyanine metal complex has been used as Y. A mixture ratio by weight of U, W, and Y is 1.0 : 2.0 : 0.15. In addition to these examples, as an organic metal complex anion and cation, there can be used general structural formulas such as WW shown in FIG. 115; WWW shown in FIG. 116; and WWWW shown in FIG. 117. As an 5 example of WW, WW1 is shown in FIG. 118; as an example of WWW, WWW1 is shown in FIG. 119; and as examples of WWWW, WWWW1 and WWWW2 are shown in FIG. 120 and FIG. 121. In the general formula of the organic metal complexes WW, WWW, and WWWW, A an A' each represent 10 heterocyclic groups of five to ten rings such as a furyl group, a thienyl group, a pyrrolyl group, a pyridyl group, a pyperidino group, pyperidyl group, a quinoryl group, and isooxazoryl group, for example, which are identical to or different from each other, 15 the groups each containing one or a plurality of hetero atoms selected from a nitrogen atom, an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom. These heterocyclic groups, for example, may have one or a plurality of aliphatic hydrocarbon groups such as a 20 methyl group, a trifluoro methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, an isopentyl group, a neopentyl group; a tert-pentyl group, a 1-methyl pentyl group, a 2- 25 methyl pentyl group, a hexyl group, an isohexyl group, and a 5-methyl hexyl group; ester groups such as a methoxy carbonyl group, a trifluoro methoxy carbonyl group, an ethoxy carbonyl group, a propoxy carbonyl group, an acetoxy group, a trifluoro acetoxy group, and benzoir oxy group; aromatic hydrocarbon groups such as a phenyl group, a biphenyl group, an o-tryl group, an 5 m-tryl group, a p-tryl group, an o-cumenyl group, an m-cumenyl group, a p-cumenyl group, a xyryl group, a mecityl group, a styryl group, a cinnamoyl group, and a naphtyl group; and further, substituents such as a carboxy group, a hydroxy group, a cyano group, and a 10 nitro group. A compound configuring an organic metal complex represented by a general formula can be obtained in accordance with a normal technique by reacting a diazonium salt having R, R21, R32, R33, R34, R41, and 15 R42 which correspond to the general formula with heterocyclic compounds such as an isoozazolone compound, an oxazolone compound, a thionaphthene compound, a pyrazolone compound, a barbizuric acid compound, a hydantoin compound, and a rhodain compound, 20 for example, having an active methylene group which is adjacent to a carbonyl group in a molecule. Y31, Y32, Y41, Y42, and Y represent hetero atoms which are identical to or different from each other, the atoms being selected from elements of the sixteenth family in 25 the periodic table such as an oxygen atom, a sulfur atom, a selenium atom, and a tellurium atom, for example. The organic metal complex represented by the general formula is generally used in a mode in which one or a plurality of metal complexes are oriented at a metal (center atom). Examples of metal elements 5 serving as the center atoms, for example, can include scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium, iron, lutenium, osmium, cobalt, rhodium, iridium, nickel, 10 palladium, platinum, copper, silver, gold, zinc, cadmium, and mercury or the like. X^ in the general formula represents a proper anodic ion including an onium ion such as alkyl ammonium ion, a pyridinium ion, and quinolinium ion, for example. 15 A test for reproduction degradation was carried out by recording an ETM modulation signal in a writeonce type R optical disk fabricated by using the above 5 types of organic dye materials, and then, obtaining reproduction count when a degree of signal modulation 20 is 0.4 or less, PRSNR is 15 or less, and SbER is 5 x 10~5 or more in the case where a track recorded by predetermined reproduction laser power was continuously reproduced (still-reproduced) at a line speed of 6.61 m/sec. The reproduction light stability is better as 25 the reproduction count increases. A result is shown in FIG. 122. It was found that the reproduction durability count is 1,000,000 or more at the reproduction laser power of 0.4 mW in an "L to H" type optical disk using a mixture dye. Namely, it was found that a mixture of a plurality of an organic metal complex simplex and an organic metal complex cation and 5 anion has excellent reproduction light durability. In particular, the fifth mixture dye of two types of organic metal complex cation and anion and an organic metal complex simplex achieved 1,500,000 or more in reproduction light durability. 10 In addition, with respect to the reflectivity obtained by measuring I11H after recording, the reflectivity was 12% in the case of the first dye "A" and 30% in the case of the second dye. The reflectivity was 14% in the case of the third dye U + W 15 + Y; the reflectivity was 22% in the case of the fourth dye B + W -I- Y; and the reflectivity was 28% in the case of the fifth dye U + W + Y. Therefore, it was experimentally found convenient that the reflectivity ranges from 14% to 28% in order to obtain the 20 reproduction light durability of 1,000,000 times or more. In addition, a novel embodiment that the following concept of constitution of a mixture dye is proper was obtained. This constitution consists of at least two 25 portions, i.e., a "recording function dye" and a "reproduction light durability function dye". An organic metal complex such as A, B, or Y can be used as the former "recording function dye". The organic metal complex is not limited to these structures or skeletons. In addition, U, V, W, WW, WWW, and WWWW can be used. Use of an anion and cation type is convenient 5 to further improve reproduction light durability. Mainly, it is preferable to use a dye of this portion having excellent performance of recording and reproducing characteristics. The latter "reproduction light durability function dye" serves to improve the 10 reproduction light durability. Although the use of one type of the dye will suffice, the use of two types is further effective. An organic metal complex such as A, B, or Y can also be used. The organic metal complex is not limited to these structures and skeletons. In 15 addition, U, V, W, WW, WWW, and WWWW can be used. The use of a cation and anion type is convenient to further improve the reproduction light durability. In particular, the use of dyes W, WW, WWW, and WWWW is preferable to improve the reproduction light 20 durability. For example, in the case where two types are used, it is convenient to carry out recording of a burst cutting area (BCA) by adjusting a maximum absorption wavelength of one dye in the range of 630 nm to 680 nm, and large BCA amplitude can be obtained. In 25 the case where a high level voltage (IBH) of a BCA signal is set to 100%, it becomes possible to set the BCA signal amplitude to 20% or more. IBL/IBH can be set to 0.80 or less when this amplitude is expressed by using a low level voltage (IBL). In addition, with respect to a mixture ratio of the "recording function dye" and the "reproduction light durability function dye", it is preferable that the "reproduction light durability function dye" range from 30% to 400% in the case where the "recording function dye" is set to 100%. It is particularly preferable that the above dye range from 150% to 300%. The best ratio should be set to 200%. It is preferable that a dye added for BCA recording range from 5% to 50%. It is particularly preferable that the dye range from 10% to 30%. The best ratio should be set to 15%. The present invention is not limited to the abovedescribed embodiments. At a stage of carrying out the invention, the present invention can be embodied by modifying constituent elements without departing from the spirit of the invention. In addition, a variety of inventions can be formed by using a proper combination of a plurality of constituent elements disclosed in the above-described embodiments. For example, some constituent elements may be eliminated from all the constituent elements shown in the embodiments. Further, the constituent elements over the different embodiments may be properly combined with each other. Examples Now, examples of the recording film will be described here. In the following examples, one-sided single layer mediums and one-sided double layer mediums were fabricated. As a substrate, there was used a polycarbonate (PC) substrate having thickness of 0.6 mm fabricated by injection molding. A groove was formed on the substrate in track pitches of 0.4 (am. A onesided single layer medium was fabricated as follows. That is, a dye was coated on the substrate in accordance with a spin coat technique. On the coated substrate, a reflection layer was formed in a sputtering technique. On the formed reflection layer, a PC substrate having thickness of 0.6 mm was adhered by using an UV curing resin. On the other hand, two methods can be used in the case of the one-sided double layer medium. In a first method, the one-sided double layer medium was fabricated as follows. On an LO substrate, a dye was coated in accordance with a spin coat technique. On the coated substrate, a semipermeable reflection layer was formed in accordance with a sputtering technique. On the formed layer, an interlayer separating layer and a groove for LI were formed in accordance with a 2P technique (photo polymer technique). Further, on the formed groove, a dye was coated again in accordance with the spin coat technique. On the coated layer, a reflection layer was formed in accordance with the sputtering technique. Lastly, a PC substrate having thickness of 0.6 mm was adhered to the formed reflection layer by using a UV curing resin. In this method, the LO-layer semipermeable reflection film was formed, and further, another layer can be formed on the formed reflection film for adjustment of optical characteristics. In a second method, the following preparation was carried out. On an LO substrate, a dye was coated in accordance with a spin coat technique. On the coated substrate, a semipermeable reflection layer was formed in accordance with a sputtering technique. In addition, on the LI substrate, first, a reflection layer is formed in accordance with a sputtering technique. On the formed reflection layer, a dye was coated in accordance with a spin coat technique. The fabricated LO and LI substrates were adhered to each other using a UV curing resin while their respective semipermeable reflection film and organic dye film were set inwardly. In this method, another layer can be inserted between an organic dye layer which is a recording layer of Ll and the UV curing resin for the purpose of stabilizing an organic dye which is a recording film material of Ll or adjusting optical characteristics. In the present embodiment, testing was carried out using mediums fabricated by both of the methods. For evaluation, a disk evaluation device ODU-1000 available from a PULSTEC Co., Ltd. was used. This device includes a blue violet semiconductor laser having a wavelength of 405 nm and an objective lens of NA = 0.65. Recording and reproducing testing was carried out under a condition for a linear velocity of 6.6 m/sec. Evaluation was carried out with respect to five characteristics below. That is, measurements of (a) SbER (Simulated bit Error Rate); (b) PRSNR (Partial Response Signal to Noise Ratio) ; (c) Modulation; (d) reflectivity of data portion; and (e) read stability of each storage medium were carried out. The evaluation criteria were defined as follows. That is, in the case where continuous readout is carried out at an SbER of 5.0 x 10~5 or less, a PRSNR of 15.0 or more, a modulation of 0.4 or more, a reflectivity of 14% or more in the case of a one-sided single layer medium or a reflectivity of 4% or more in each of the LO and LI mediums in the case of one-sided double layer, at power of 0.4 mW in the case of a one-sided single layer medium and at any good power of 0.4 mW to 0.8 mW in the case of a one-sided double layer medium for read stability, even if readout was carried out for 1,000,000 times or more, characteristics (a) to (e) must achieve their target values. Read power in the one-sided double layer medium was selected as a condition such that SN ratios and signal amplitudes of reproduction signals are substantially equal to each other in LO and LI. This is because optical characteristics (LO reflectivity and transmittance, LI reflectivity) and sensitivity of a medium and a signal amplitude and SN ratio of reflection signal are different depending on a dye of a medium and a material and a film thickness or the like of the reflection film. However, the read power values of LO and LI are often identical to each other. In the case where all the characteristics met the target values, the storage medium was defined as "good", and if only one characteristic failed to meet its target value, the medium was defined as being "unacceptable". There were used three types of organic dye recording materials (occasionally simply referred to as dye), i.e., (1) cation-anion based; (2) organic metal complex (azo based); and (3) mixture dye of cationanion based and organic metal complex (azo based). The used reflection films are binary Ag allows, i.e., AgAu, AgBi, AgCa, AgCe, AgCo, AgGa, AgLa, AgMg, AgN, AgNi, AgNd, AgPd, AgY, AgW, AgZr; and tertiary Ag alloys, i.e., AgAlMg, AgAuBi, AgBiGa, AgAuCo, AgAuCe, AgAuNi, AgAuMg, AgBiMg, AgBiN, AgBiPd, and AgBiZr; and advantageous effect in the case where additive elements of group 1 and group 2 and N (nitrogen) were added at the same time was verified. As a film forming method, there was used each of Ag alloy targets described previously or there was used a multi-dimensional simultaneous sputtering in which a sputtering condition was adjusted so as to obtain a desired constitution. Reaction with nitrogen was carried out by using as a sputtering gas a mixture gas of Ar and N (nitrogen) instead of only Ar. The constitution, film thickness, and substrate shape of dyes and reflection films were adjusted, respectively, so that signal characteristics are good. Additive amounts of additive elements in an Ag alloy reflection film used in each of examples were four levels of 0.05 at%, 1 at%, 2 at%, and 5 at%, and three levels of (1), (2), and (3) were used for organic dye materials. Therefore, a total number of sample types produced in examples were 12. FIG. 123 and FIG. 124 each show additive element names of Ag-alloy reflection films used in examples, and FIG. 125 shows Ag-alloy reflection films and amounts of additive elements used in comparative examples and a chart of combination with organic dye materials. As organic dye material (4), there was used a conventionally used dye material, i.e., a phthalocyanine based organic dye and super-green dye (IRAPHOR Utragreen MX available from Ciba Speciality Chemicals). Example 1 In example 1, a one-sided single layer storage medium was produced, and testing was carried out. Au was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as additive amounts; and three types (1), (2), and (3) were used as organic dye materials for recording films. In order to cover all combinations of amounts of additive elements and dye materials, all combinations, 12 types of storage mediums were produced, and evaluation of the recording and reproducing characteristics were carried out. FIG. 126 specifically exemplifies constitutions of reflection films and combinations of organic dye materials for recording films. When the characteristics (a) to (e) of the produced storage mediums were evaluated, the evaluation results were obtained as shown in FIG. 127. As is evident from these results, each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 2 In example 2, one-sided single layer and double layer storage mediums were produced. Bi was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) was used as organic dye materials for recording films. As in example 1, 12 combinations of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to the one-sided double layer storage medium, a medium whose Bi additive amounts are 0.05 at% and 1 at% was produced, and with respect to the one-sided single layer storage medium, a medium whose Bi additive amounts are 1 at%, 2 at%, and 5 at% was produced, respectively, and evaluation was carried out. FIG. 128 specifically exemplifies constitutions of reflection films and combinations of organic dye materials for recording films. When the characteristics (a) to (e) of the produced storage mediums were evaluated, the evaluation results were obtained as shown in FIG. 129. In FIG. 129, data represented with "double layer" indicates data on a one-sided double layer medium in the case where there exists data on both of a one-sided single layer medium and a one-sided double layer medium. As is evident from these results, each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the one-sided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 3 In example 3, as in example 1, a one-sided single layer storage medium was produced. Ca was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 4 In example 4, as in example 1, a one-sided single layer storage medium was produced. Ce was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 5 In example 5, as in example 1, a one-sided single layer storage medium was produced. Co was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 6 In example 6, a one-sided single layer and a onesided double layer storage mediums were produced. Ga was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Ga additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Ga additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the one-sided double layer medium in both of LO and LI and 14% or more relevant to the onesided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 7 In example 7, as in example 1, a one-sided single layer storage medium was produced. La was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10"^ or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 8 In example 8, one-sided single layer and double layer storage mediums were produced. Mg is used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Mg additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Mg additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the onesided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 9 In example 9, as in example 1, a one-sided single layer storage medium was produced. N was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 10 In example 10, as in example 1, a one-sided single layer storage medium was produced. Ni was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 11 In example 11, as in example 1, a one-sided single layer storage medium was produced. Nd was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 12 In example 12, as in example 1, a one-sided single layer storage medium was produced. Pd was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recordingj and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; Sl^ER of 5.0 x 10~^ or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; an of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 13 In example 13, as in example 1, ^ one-sided single layer storage medium was produced. Y\|was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types!(1), (2), and (3) were used as organic dye materials fojf: recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recordingjand reproducing characteristics were carried out. Eacph of the storage mediums achieved the target values; Slj)ER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; ancjl read stability of 1,000,000 times or more. Therefor4, each of the storage mediums obtained "good" characteristics. Example 14 In example 14, as in example 1, ^ one-sided single layer storage medium was produced. W was used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 atj% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 15 In example 15, a one-sided single layer and a onesided double layer storage mediums were produced. Zr is used as an additive element of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as amounts of additives; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Zr additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Zr additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the one-sided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 16 In example 16, as in example 1, a one-sided single layer storage medium was produced, Al and Mg were used as additive elements of an Ag-alloy reflection film, four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as total additive amounts of Al and Mg; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 17 In example 17, a one-sided single layer and a onesided double layer storage mediums were produced. Au and Bi were used as additive elements of an Ag-alloy reflection film, four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as total additive amounts of Au and Bi; and three types (1), (2), and (3) were used as organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Ga additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Ga additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the one-sided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 18 In example 18, a one-sided single layer and a onesided double layer storage mediums were produced. Bi and Ga were used for additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Bi and Ga; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Ga additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Ga additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the onesided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 19 In example 19, as in example 1, a one-sided single layer storage medium was produced. Au and Ce were used as additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Au and Ce; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 20 In example 20, as in example 1, a one-sided single layer storage medium was produced. Au and Co were used as additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Au and Co; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 21 In example 21, as in example 1, a one-sided single layer storage medium was produced. Au and Ni were used as additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Au and Ni; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 22 In example 22, as in example 1, a one-sided single layer storage medium was produced. Au and Mg were used as additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Au and Mg; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 23 In example 23, a one-sided single layer and a onesided double layer storage mediums were produced. Bi and Mg were used for additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Bi and Mg; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Ga additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Ga additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the onesided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 24 In example 24, a one-sided single layer and a onesided double layer storage mediums were produced. Bi and N were used for additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Bi and N; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. With respect to a medium whose Ga additive amounts are 0.05 at% and 1 at%, a one-sided double layer storage medium was produced, and with respect to a medium whose Ga additive amounts were 2 at% and 5 at%, a one-sided single layer storage medium was produced, respectively, and evaluation was carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 4% or more relevant to the one-sided double layer medium in both of LO and LI and 14% or more relevant to the one-sided single layer medium; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 25 In example 25, as in example 1, a one-sided single layer storage medium was produced. Bi and Pd were used as additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Bi and Pd; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Example 26 In example 26, as in example 1, a one-sided single layer storage medium was produced. Bi and Zr were used as additive elements of an Ag-alloy reflection film; four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used for total additive amounts of Bi and Zr; and three types (1), (2), and (3) were used for organic dye materials for recording films. As in example 1, 12 types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. Each of the storage mediums achieved the target values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation of 0.4 or more; reflectivity of 14% or more; and read stability of 1,000,000 times or more. Therefore, each of the storage mediums obtained "good" characteristics. Comparative Example 1 In comparative example 1, as in example 1, a onesided single layer storage medium was produced. Al was used as an additive element of an Ag-alloy reflection film; two types of 0.04 at% and 6 at% were used as additive amounts; and a phthalocyanine based organic dye and super-green dye (IRGAPHOR Ultragreen MX available from Ciba Speciality Chemicals) were used as organic dye materials for recording films. Three types of storage mediums were produced, and evaluation of recording and reproducing characteristics were carried out. In the case where the additive amount of Al contained in the Ag alloy was defined as 6 at%, the modulation and reflectivity did not meet 0.4 or more and 14% or more which are their target values, and was "unacceptable". In addition, in the case where the additive amount of Al contained in the Ag alloy was defined as 0.04 at%, in particular, read stability did not achieve 1,000,000 times or more. Therefore, each of the storage mediums achieved only "unacceptable" characteristics. Comparative example 2 In comparative example 2, as in example 1, a onesided single layer storage medium was produced. Cu was used as an additive element of an Ag-alloy reflection film; two types of 0.04 at% and 6 at% were used as additive amounts; and a phthalocyanine based organic dye and super-green dye (IRGAPHOR Ultragreen MX available from Ciba Speciality Chemicals) were used as organic dye materials for recording films. A storage medium was produced, and evaluation of recording and reproducing characteristics were carried out. In the case where the additive amount of Cu contained in the Ag alloy was defined as 6 at%, the modulation and reflectivity did not meet 0.4 or more and 14% or more which are their target values, and was "unacceptable". In addition, in the case where the additive amount of Cu contained in the Ag alloy was defined as 0.04 at%, in particular, read stability did not achieve 1,000,000 times or more. Therefore, each of the storage mediums achieved only "unacceptable" characteristics. Comparative example 3 In comparative example 3, as in example 1, a onesided single layer storage medium was produced. Pd was used as an additive element of an Ag-alloy reflection film; two types of 0.04 at% and 6 at% were used as additive amounts; and a phthalocyanine based organic dye and super-green dye (IRGAPHOR Ultragreen MX available from Ciba Speciality Chemicals) were used as organic dye materials for recording films. A storage medium was produced, and evaluation of recording and reproducing characteristics were carried out. In the case where the additive amount of Pd contained in the Ag alloy was defined as 6 at%, the modulation and reflectivity did not meet 0.4 or more and 14% or more which are their target values, and was "unacceptable". In addition, in the case where the additive amount of Pd contained in the Ag alloy was defined as 0.04 at%, in particular, read stability did not achieve 1,000,000 times or more. Therefore, each of the storage mediums achieved only "unacceptable" characteristics. According to an embodiment, a storage medium comprises a transparent resin substrate on which a groove is formed; a recording layer formed on the groove on the transparent resin substrate, the recording layer using an organic dye material and recording information with a light beam of 620 nm or less in wavelength; a reflection layer formed on the recording layer; and a prevention layer formed between the recording layer and the reflection layer, the prevention layer preventing degradation of characteristics of the reflection layer. In the storage medium, the reflection layer may comprise Ag and an additive element selected from Al, Au, Bi, Ca, Ce, Co, Cu, Ga, La, Mg, N, Ni, Nd, Pd, Pt, Rh, Y, W, and Zr. In the storage medium, a total amount of the additive elements may range from 0.05 at% to 5 at%. While certain embodiments of the inventions have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel methods and systems described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the methods and systems described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions. We claim: 1. A storage medium comprising: a transparent layer (2-2) which passes light; a recording layer (3-2) formed of an organic dye material, the light passed through the transparent layer being incident to the recording layer; a reflection layer (4-2) formed of Ag alloy and reflecting the light passed through the recording layer; and a prevention layer (8) formed at an interface between the reflection layer (4-2) and the recording layer (3-2) and preventing degradation of characteristic of the reflection layer (4-2), wherein the recording layer comprises an unrecorded portion, a maximum absorption wavelength (λmax write) at which a light absorbance in the unrecorded portion is maximum is longer than 405nm, a light absorbance in the unrecorded portion at a wavelength of 355 nm is not smaller than 40% of the light absorbance at the maximum absorption wavelength, information is recordable by light having a wavelength of 405nm, an intensity of light reflected by the reflection layer and passed through a recording portion of the recording layer is higher than an intensity of light reflected by the reflection layer and passed through the unrecorded portion, and the reflection layer comprises silver Ag and an additive element which prevents degradation of recording and reproducing characteristics due to reaction with silver Ag and the organic dye material, the additive element being selected from aluminium A1; gold Au; bismuth Bi; calcium Ca; cerium Ce, cobalt Co, gallium Ga, lanthanum La; magnesium Mg; nitrogen N; nickel Ni; neodium Nd; palladium Pd; yttrium Y; tungsten W and zirconium Zr. 2. The storage medium as claimed in claim 1, wherein the additive element ranges from 0.05 at% to 5 at% in a total atom number of additive element relative to Ag content. 3. The storage medium as claimed in claim 1, wherein the prevention layer prevents a recording and reproduction characteristic change due to reaction between the reflection layer (4-2) and the recording layer. 4. A method for reproducing information recorded in a storage medium as claimed in one of claims 1 to 3, the method comprising: irradiating the storage medium with a light beam of 405 nm in wavelength; and reproducing information recorded in the storage medium based on a reflection light beam of the irradiated light beam. 5. A method for recording information in a storage medium as claimed in one of claims 1 to 3, the method comprising: irradiating the storage medium with a light beam of 405 nm in wavelength based on information to be recorded in the storage medium; and recording information in the storage medium based on the irradiated light beam.

Full Text

TITLE OF THE INVENTION
STORAGE MEDIUM, REPRODUCING METHOD, AND RECORDING
METHOD
BACKGROUND OF THE INVENTION
One embodiment of the invention relates to a
storage medium such as an optical disk, a reproducing
method, and a recording method of the storage medium
capable of recording and reproducing information with a
laser light beam having a short wavelength such as a
blue laser light beam.
As is well known, in recent years, with prevalence
of personal computers or the like, media for
accumulating digital data has been increasingly
important. For example, currently, an information
storage medium capable of digitally recording and
reproducing video image information and voice
information or the like for a long time is prevalent.
In addition, an information storage medium for digital
recording and reproduction is used for a mobile device
such as a cellular phone.
As an information storage medium of this type,
there is often utilized a medium of disk shape because
the medium has a large capacity of recording
information; has random access performance capable of
speedily making a search for desired recording
information; and moreover, the medium is small in size
and light in weight, excellent in storage property and
portability, and is inexpensive.
In addition, as an information storage medium of
such a disk shape, currently, there is mainly used a so
called optical disk capable of recording and
reproducing information in a non-contact manner by
irradiating a laser light beam. This optical disk
primarily conforms to a CD (Compact Disk) standard or a
DVD (Digital Versatile Disk) standard, and is
compatible with both of these standards.
There are three types of optical disks, i.e., a
read-only type which cannot record information such as
a CD-DA (Digital Audio), a CD-ROM (Read-Only Memory), a
DVD-V (Video), or a DVD-ROM and the like; a write-once
type capable of recording information only once such as
a CD-R (Recordable) or a DVD-R and the like; and a
rewritable type capable of rewriting information any
times such as a CD-RW (Rewritable) or a DVD-RW and the
like.
Among them, as a recordable disk, a write-once
type optical disk using an organic dye for a recording
layer is the most prevalent because of its low
manufacturing cost. This is because, if an information
recording capacity exceeds 700 MB (Mega Bytes), there
is almost no need for erasing recorded information and
rewriting new information, and eventually only one
recording suffices.
In the write-once type optical disk using the
organic dye for the recording layer, after a recording
area (track) specified by a groove is irradiated with a
laser light beam and a resin substrate is excessively
heated to its glass transition point Tg or more, an
organic dye film in the groove causes an opto-chemical
reaction and produces a negative pressure. As a
result, the resin substrate is deformed in the groove.
A recording mark is formed by utilizing this
deformation.
A typical organic dye used for a CD-R whose
wavelength of a recording and reproducing laser light
beam is about 780 nm includes a phthalocyanine based
dye such as IRGAPHOR Ultragreen MX available from Ciba
Speciality Chemicals. In addition, a typical organic
dye used for a DVD-R whose wavelength of a recording
and reproducing laser light beam is about 650 nm
includes an azo metal complex based dye available from
Mitsubishi Kagaku Media Co., Ltd.
In the meantime, in comparison with a current
optical disk, in a next generation optical disk which
achieves recording and reproduction with higher density
and higher performance, a blue laser light beam whose
wavelength is short at about 405 nm is used as a
recording and reproducing laser light beam. However,
an organic dye material capable of obtaining
practically sufficient recording and reproducing
characteristics by using a light beam having such a
short wavelength has not been developed yet.
In document 1 (Jpn. Pat. Appln. KOKAI Publication
No. 2002-74740), there is disclosed an optical storage
medium having a longer wavelength than a wavelength of
a write light beam in absorption extremity of an
organic dye compound contained in a recording layer.
However, in this document 1, for example, there is
nowhere described a configuration of enhancing
performance of an optical disk itself such as
durability in the case where a mark recorded in an
optical disk has been continuously reproduced by a blue
laser light pickup. There is a need for a signal not
to be degraded in the case where a certain track is
continuously reproduced. A write-once type optical
disk using an excellent dye in reproduction light
stability must be provided.
In document 2 (Jpn. Pat. Appln. KOKAI Publication
No. 2004-139712), there is disclosed an Ag-group alloy
reflection film or a semipermeable reflection film for
an optical information recording medium, the Ag-group
alloy reflection film being made of an Ag-group alloy
containing 0.005 at% to 0.40 at% of Bi and/or Sb in
total. However, document 2 merely discloses a
reflection film simplex, and does not describe how an
organic dye component is used as a recording layer and
how the above-described storage medium is configured as
using a recording and reproducing light beam having a
short wavelength.
As has been described above, a conventional
storage medium using an organic dye material is not
sufficient in reproduction durability count.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
A general architecture that implements the various
feature of the invention will now be described with
reference to the drawings. The drawings and the
associated descriptions are provided to illustrate
embodiments of the invention and not to limit the scope
of the invention.
FIG. 1 is an exemplary view of the contents of
constituent elements of an information storage medium
and a combination method in the present embodiment;
FIGS. 2A, 2B, and 2C show exemplary views of
difference in principle of obtaining reproduction
signal between phase change type recording film and
organic dye based recording film in which FIG. 2A shows
a phase change type recording film and FIG. 2B shows an
organic dye based recording film;
FIG. 3 is an exemplary view showing a specific
structural formula of the specific content "(A3) azometal
complex + Cu" of the information storage medium
constituent elements shown in FIG. 1;
FIG. 4 is an exemplary view showing an example of
light absorption spectrum characteristics of an organic
dye recording material used for a current DVD-R disk;
FIGS. 5A and 5B show exemplary views of difference
of light reflection layer shape in pre-pit/pre-groove
areas between phase change type recording film and
organic dye based recording film in which FIG. 5A shows
a phase change recording film and FIG. 5B shows an
organic dye recording film;
FIGS. 6A and 6B are exemplary views each showing a
plastic deformation situation of a specific transparent
substrate 2-2 at a position of a recording mark 9 in a
write-once type information storage medium using a
conventional organic dye material;
FIGS. 7A, 7B and 7C are exemplary views which
relate to a shape or dimensions relating to a recording
film, which easily causes a principle of recording;
FIGS. 8A, 8B and 8C are exemplary views showing
characteristics of the shape and dimensions of the
recording film;
FIG. 9 is an exemplary view of light absorption
spectrum characteristics in an unrecorded state in a
"High to Low" (hereinafter, abbreviated to as an "H-L")
recording film;
FIG. 10 is an exemplary view of light absorption
spectrum characteristics in a recording mark in the "HL"
recording film;
FIG. 11 is an exemplary view of a structure in an
embodiment of an information recording/reproducing
apparatus according to the invention;
FIG. 12 is an exemplary view showing a detailed
structure of peripheral sections including a sync code
position sampling unit 145 shown in FIG. 11;
FIG. 13 is an exemplary view showing a signal
processor circuit using a slice level detecting system;
FIG. 14 is an exemplary view showing a detailed
structure in a slicer 310 of FIG. 13;
FIG. 15 is an exemplary view showing a signal
processor circuit using a PRML detecting technique;
FIG. 16 is an exemplary view showing a structure
in a Viterbi decoder 156 shown in FIG. 11 or FIG. 15;
FIG. 17 is an exemplary view showing a state
transition in a PR(1, 2, 2, 2, 1) class;
FIG. 18 is an exemplary view showing a wavelength
(write strategy) of a recording pulse which carries out
trial writing for a drive test zone;
FIG. 19 is an exemplary view showing a definition
of a recording pulse shape;
FIGS. 20A, 20B and 20C are exemplary views of a
recording pulse timing parameter setting table;
FIGS. 21A, 21B and 21C are exemplary views
relating to values of each parameter used when optimal
recording power is checked;
FIG. 22 is an exemplary view showing a light
reflection factor range of non-recording unit in an
"H-L" recording film and a "Low to High" (hereinafter,
abbreviated to as an "L-H") recording film;
FIG. 23 is an exemplary view of a polarity of a
detection signal detected from the "H-L" recording film
and the "L-H" recording film;
FIG. 24 is an exemplary view showing a comparison
in light reflection factor between the "H-L" recording
film and the "L-H" recording film;
FIG. 25 is an exemplary view of light absorption
spectrum characteristics in an unrecorded state in the
"L-H" recording film;
FIG. 26 is an exemplary view showing a light
absorption spectrum characteristic change in a recorded
state and an unrecorded state in the "L-H" recording
film;
FIG. 27 is an exemplary general structural formula
of a cyanine dye utilized for a cation portion of the
"L-H" recording film;
FIG. 28 is an exemplary general structural formula
of a styril dye utilized for a cation portion of the
"L-H" recording film;
FIG. 29 is an exemplary general structural formula
of a monomethine cyanine dye utilized for a cation
portion of the "L-H" recording film;
FIG. 30 an exemplary general structural formula of
a formazane metal complex utilized for an anion portion
of the "L-H" recording film;
FIG. 31 is an exemplary view showing an example of
a structure and dimensions in an information storage
medium;
FIG. 32 is an exemplary view showing a value of a
general parameter in a read-only type information
storage medium;
FIG. 33 is an exemplary view showing a value of a
general parameter in a write-once type information
storage medium;
FIG. 34 is an exemplary view showing a value of a
general parameter in a rewritable type information
storage medium;
FIGS. 35A, 35B and 35C are exemplary views
comparing a detailed data structure in a system lead-in
area SYLDI and a data lead-in area DTLDI in a variety
of information storage mediums;
FIG. 36 is an exemplary view showing a data
structure in an RMD deprecation zone RDZ and a
recording position management zone RMZ, which exist in
the write-once type information storage medium;
FIGS. 37A, 37B, 37C, 37D, 37E and 37F are
exemplary views each showing a comparison of a data
structure in a data area DTA and a data lead-out area
DTLDO in a variety of information storage mediums;
FIG. 38 is an exemplary view showing a data
structure in recording position management data RMD;
FIG. 39 is an exemplary view showing a structure
of a border area in a write-once type information
storage medium different from that in FIG. 38;
- 10 -
FIG. 40 is an exemplary view showing a structure
of a border area in a write-once type information
storage medium;
FIG. 41 is an exemplary view showing a data
structure in a control data zone CDZ and an R physical
information zone RIZ;
FIG. 42 is an exemplary view showing specific
information contents in physical format information PFI
and R physical information format information R_PFI;
FIG. 43 is an exemplary view showing a comparison
of the contents of detailed information recorded in
allocation place information on a data area DTA;
FIG. 44 is an exemplary view showing a detailed
data structure in recording position management data
RMD;
FIG. 45 is an exemplary view showing a detailed
data structure in recording position management data
RMD;
FIG. 46 is an exemplary view showing a detailed
data structure in recording position management data
RMD;
FIG. 47 is an exemplary view showing a detailed
data structure in recording position management data
RMD;
FIG. 48 is an exemplary view showing a detailed
data structure in recording position management data
RMD;
FIG. 49 is an exemplary view showing a detailed
data structure in recording position management data
RMD;
FIG. 50 is an exemplary view showing a data
structure in a data ID;
FIG. 51 is an exemplary view adopted to explain
another embodiment relevant to a data structure in
recording position management data RMD;
FIG. 52 is an exemplary view adopted to explain
the other embodiment relevant to a data structure in
recording position management data RMD;
FIG. 53 is an exemplary view showing another data
structure in an RMD field 1;
FIG. 54 is an exemplary view of another embodiment
relating to physical format information and R physical
format information.
FIG. 55 is an exemplary view showing another
embodiment relating to a data structure in a control
data zone;
FIG. 56 is an exemplary view schematically showing
converting procedures for configuring a physical sector
structure;
FIG. 57 is an exemplary view showing a structure
in a data frame;
FIGS. 58A and 58B are exemplary views each showing
an initial value assigned to a shift register when
creating a frame after scrambled and a circuit
configuration of a feedback resistor;
FIG. 59 is an exemplary view of an ECC block
structure;
FIG. 60 is an exemplary view of a frame
arrangement after scrambled;
FIG. 61 is an exemplary view of a PO interleaving
method;
FIGS. 62A and 62B are exemplary views each showing
a structure in a physical sector;
FIG. 63 is an exemplary view of the contents of a
sync code pattern;
FIG. 64 is an exemplary view showing a detailed
structure of an ECC block after PO interleaved, shown
in FIG. 61;
FIG. 65 is an exemplary view showing an example of
a light absorption spectrum characteristic change
before and after recorded, in an "H-L" recording film;
FIG. 66 is an exemplary view showing an example of
a light absorption spectrum characteristic change
before and after recorded, in an "L-H" recording film;
FIGS. 67A and 67B are exemplary views each showing
a molecular structure changing situation in an azo
metal complex;
FIG. 68 is an exemplary view showing another
example of a light absorption spectrum change before
and after recorded, in an "L-H" recording film;
FIG. 69 is an exemplary view showing another
example of a light absorption spectrum change before
and after recorded, in an "H-L" recording film;
FIG. 70 is an exemplary view showing still another
example of a light absorption spectrum change before
and after recorded, in an "H-L" recording film;
FIGS. VIA and 71B are exemplary illustrative cross
section of a pre-pit in a system lead-in area SYLDI;
FIG. 72 is an exemplary view of a reference code
pattern;
FIG. 73 is an exemplary view showing a comparison
in data recording format of each of a variety of
information storage mediums;
FIGS. 74A and 74B are exemplary views of a
comparison with a conventional example of a data
structure in a variety of information storage mediums;
FIG. 75 is an exemplary view of a comparison with
a conventional example of a data structure in a variety
of information storage mediums;
FIG. 76 is an exemplary view of 180-degree phase
modulation and an NRZ technique in wobble modulation;
FIG. 77 is an exemplary view of a relationship
between a wobble shape and an address bit in an address
bit area;
FIGS. 78A, 78B, 78C and 78D are comparative
exemplary views of a positional relationship in a
wobble sink pattern and a wobble data unit;
FIG. 79 is an exemplary view relating to a data
structure in wobble address information contained in a
write-once type information storage medium;
FIG. 80 is an exemplary view of an allocation
place in a modulation area on a write-once type
information storage medium;
FIG. 81 is an exemplary view showing an allocation
place in a physical segment on a write-once type
information storage medium;
FIGS. 82A and 82B are exemplary views of a layout
in a recording cluster;
FIG. 83 is an exemplary view showing a data
recording method for rewritable data recorded on a
rewritable-type information storage medium;
FIG. 84 is an exemplary view of a data random
shift of the rewritable data recorded on a rewritabletype
information storage medium;
FIG. 85 is an exemplary view of a method for
additionally describing write-once type data recorded
on a write-once type information storage medium;
FIG. 86 is an exemplary view of specification of
an optical disk in B format;
FIG. 87 is a view showing an exemplary
configuration of picket codes (error correcting blocks
in the B format;
FIG. 88 is an exemplary view of a wobble address
in B format;
FIG. 89 is an exemplary view showing a detailed
structure of a wobble address obtained by combining an
MSK system and an STW system with each other;
FIG. 90 is an exemplary view showing a unit of 56
wobbles and an ADIP unit expressing a bit of "0" or
"1";
FIG. 91 is an exemplary view showing an ADIP word
consisting of 83 ADIP units and showing an address;
FIG. 92 is an exemplary view showing an ADIP word;
FIG. 93 is an exemplary view showing 15 nibbles
contained in an ADIP word;
FIG. 94 is an exemplary view showing a track
structure in B format;
FIG. 95 is an exemplary view showing a recording
frame in B format;
FIGS. 96A and 96B are exemplary views each showing
a structure of a recording unit block;
FIG. 97 is an exemplary view showing data run in
and data run out structures;
FIG. 98 is an exemplary view showing allocation of
data relating to a wobble address;
FIGS. 99A and 99B are exemplary views each showing
an area of guard 3 arranged at the end of a data run
out area;
FIGS. 100A, 100B, 100C, 100D, 100E, and 100F are
exemplary views showing a method for producing a writeonce
type information storage medium;
FIGS. 101A, 101B, and 101C are exemplary views
showing a method for producing a stamper for producing
a write-once type information storage medium;
FIGS. 102A, 102B, 102C, 102D, and 102E are
exemplary views showing a method for producing a
stamper for producing a write-once type information
storage medium;
FIG. 103 is an exemplary view showing a spin coat
condition for producing a write-once type information
storage medium;
FIG. 104 is an exemplary a view illustrating a
relationship between a groove and a land in a writeonce
type information storage medium;
FIG. 105 is an exemplary a waveform chart showing
an example of a signal recorded to carry out a test of
recording and reproducing evaluation in a write-once
type information storage medium;
FIG. 106 is an exemplary view showing a general
structural formula of organic metal complex simplex
"A" ;
FIG. 107 is an exemplary view showing a general
structural formula of organic metal complex simplex B;
FIG. 108 is an exemplary view showing a general
structural formula of organic dye metal complex cation
and anion U;
FIG. 109 is an exemplary view showing a general
structural formula of organic dye metal complex cation
and anion W;
FIG. 110 is an exemplary view showing a general
structural formula of azo phthalocyanine metal
complex Y;
FIG. Ill is an exemplary view showing an example
Ul of organic dye metal complex cation and anion U;
FIG. 112 is an exemplary view showing an example
Wl of organic metal complex cation and anion W;
FIG. 113 is an exemplary view showing a formazane
metal complex V;
FIG. 114 is an exemplary view showing an example
of organic metal complex cation and anion W;
FIG. 115 is an exemplary view showing a general
structural formula of organic metal complex cation and
anion WW;
FIG. 116 is an exemplary view showing a general
structural formula of organic metal complex cation and
anion WWW;
FIG. 117 is an exemplary view showing a general
structural formula of organic metal complex cation and
anion WWWW;
FIG. 118 is an exemplary view showing an example
of organic metal complex cation and anion WW1;
FIG. 119 is an exemplary view showing an example
of organic metal complex cation and anion WWWl;
FIG. 120 is an exemplary view showing an example
of organic metal complex cation and anion WWWWl;
FIG. 121 is an exemplary view showing an example
of organic metal complex cation and anion WWWW2;
FIG. 122 is an exemplary view showing a
relationship (measurement result) between reproduction
laser power and reproduction durability count for each
organic dye material;
FIG. 123 is an exemplary view showing examples of
binary types;
FIG. 124 is an exemplary view showing examples of
tertiary types;
FIG. 125 is an exemplary view showing comparative
examples;
FIG. 126 is an exemplary view showing combinations
of reflection film materials and constitution and
organic dye materials for recording films of example 1;
FIG. 127 is an exemplary view showing evaluation
results of example 1;
FIG. 128 is an exemplary view showing combinations
of reflection film materials and constitution and
organic dye materials for recording films of example 1;
and
FIG. 129 is an exemplary view showing evaluation
results of example 2.
DETAILED DESCRIPTION OF THE INVENTION
Various embodiments according to the invention
will be described hereinafter with reference to the
accompanying drawings. In general, according to one
embodiment of the invention, a storage medium comprises
a recording layer using an organic dye material formed
on a substrate; and a reflection layer comprises Ag and
an additive element which prevents degradation of
recording and reproducing characteristics due to
reaction with Ag and the organic dye material.
Hereinafter, embodiments of a recording medium and
a method for recording and reproducing the recording
medium according to the invention will be described
with reference to the accompanying drawings.
Summary of characteristics and advantageous effect
of the invention
1) Relationship between track pitch/bit pitch and
optimal recording power:
Conventionally, in the case of a principle of
recording with a substrate shape change, if a track
pitch is narrowed, a "cross-write" or a "cross-erase"
occurs, and if bit pitches are narrowed, an inter-code
crosstalk occurs. As in the present embodiment, since
a principle of recording without a substrate shape
change is devised, it becomes possible to achieve high
density by narrowing track pitches/bit pitches. In
addition, at the same time, in the above described
principle of recording, recording sensitivity is
improved, enabling high speed recording and multilayering
of a recording film because optimal recording
power can be lowly set.
2) In optical recording with a wavelength of
620 nm or less, an ECC block is composed of a
combination of a plurality of small ECC blocks and each
item of data ID information in two sectors is disposed
in a small ECC block which is different from another:
According to the embodiment, as shown in FIG. 2B,
a local optical characteristic change in a recording
layer 3-2 is a principle of recording, and thus, an
arrival temperature in the recording layer 3-2 at the
time of recording is lower than that in the
conventional principle of recording due to plastic
deformation of a transparent substrate 2-2 or due to
thermal decomposition or gasification (evaporation) of
an organic dye recording material. Therefore, a
difference between an arrival temperature and a
recording temperature in a recording layer 3-2 at the
time of playback is small. In the present embodiment,
an interleaving process between small ECC blocks and
data ID allocation are contrived in one ECC block,
thereby improving reproduction reliability in the case
where a recording film is degraded at the time of
repetitive playback.
3) Recording is carried out by light having a
wavelength which is shorter than 620 nm, and a recorded
portion has a higher reflection factor than a nonrecording
portion:
Under the influence of absorption spectrum
characteristics of a general organic dye material,
under the control of light having a wavelength which is
shorter than 620 nm, the light absorbance is
significantly lowered, and recording density is
lowered. Therefore, a very large amount of exposure is
required to generate a substrate deformation which is a
principle of recording in a conventional DVD-R. By
employing an "Low to High (hereinafter, abbreviated to
as L-H) organic dye recording material" whose
reflection factor is increased more significantly than
that of an unrecorded portion in a portion (recording
mark) recorded as in the present embodiment, a
substrate deformation is eliminated by forming a
recording mark using a "discoloring action due to
dissociation of electron coupling", and recording
sensitivity is improved.
4) "L-H" organic dye recording film and PSK/FSK
modulation wobble groove:
Wobble synchronization at the time of playback can
be easily obtained, and reproduction reliability of a
wobble address is improved.
5) "L-H" organic dye recording film and
reproduction signal modulation degree rule:
A high C/N ratio relating to a reproduction signal
from a recording mark can be ensured, and reproduction
reliability from the recording mark is improved.
6) Light reflection factor range in "L-H" organic
dye recording film and mirror section:
A high C/N ratio relating to a reproduction signal
from a system lead-in area SYLDI can be ensured and
high reproduction reliability can be ensured.
7) "L-H" organic dye recording film and light
reflection factor range from unrecorded area at the
time of on-track:
A high C/N rate relating to a wobble detection
signal in an unrecorded area can be ensured, and high
reproduction reliability relevant to wobble address
information can be ensured.
8) "L-H" organic dye recording film and wobble
detection signal amplitude range:
A high C/N ratio relating to a wobble detection
signal can be ensured, and high reproduction
reliability relevant to wobble address information can
be ensured.
«Table of Contents»
Chapter 0: Description of Relationship between
Wavelength and the Present Embodiment
Wavelength used in the present embodiment.
Chapter 1: Description of Combination of
Constituent Elements of Information Storage Medium in
the Present Embodiment:
FIG. 1 shows an illustration of the contents of
constituent elements of the information storage medium
in the present embodiment.
Chapter 2: Description of Difference in
reproduction signal between Phase Change Recording Film
and Organic Dye Recording Film
2-1) Difference in Principle of
Recording/Recording Film and Difference in Basic
Concept Relating to Generation of Reproduction
Signal . . . Definition of A,max Write
2-2) Difference of Light Reflection Layer Shape in
Pre-pit/Pre-groove Area
Optical reflection layer shape (difference in spin
coating and sputtering vapor deposition) and influence
on a reproduction signal.
Chapter 3: Description of Characteristics of
Organic Dye Recording Film in the Present Embodiment
3-1) Problem(s) relevant to achievement of high
density in write-once type recording film (DVD-R) using
conventional organic dye material
3-2) Description of basic characteristics common
to organic dye recording films in the present
embodiment:
Lower limit value of recording layer thickness,
channel bit length/track pitch in which advantageous
effect is attained in the invention, repetitive
playback enable count, optimal reproduction power,
Rate between groove width and land width
Relationship with wobble address format
Relationship in recording layer thickness between
groove section and land section
Technique of improving error correction capability
of recording information and combination with PRML
3-3) Recording characteristics common to organic
dye recording films in the present embodiment
Upper limit value of optimal recording power
3-4) Description of characteristics relating to a
"High to Low (hereinafter, abbreviated to as H-L)"
recording film in the present embodiment:
Upper limit value of reflection factor in
unrecorded layer
Relationship between a value of X,max write anc^ a
value oflmax (absorbance maximum wavelength at
unrecorded/recorded position)
Relative values of reflection factor and degree of
modulation at unrecorded/recorded position and light
absorption values at reproduction wavelength ... n-k
range
Relationship in upper limit value between required
resolution characteristics and recording layer
thickness
Chapter 4:Description of Reproducing Apparatus or
Recording/Reproducing Apparatus and Recording
Condition/Reproducing Circuit
4-1) Description of structure and characteristics
of reproducing apparatus or recording/reproducing
apparatus in the present embodiment: Use wavelength
range, NA value, and RIM intensity
4-2) Description of reproducing circuit in the
present embodiment
4-3) Description of recording condition in the
present embodiment
Chapter 5: Description of Specific Embodiments of
Organic Dye Recording Film in the Present Embodiment
5-1) Description of characteristics relating to
"L-H" recording film in the present embodiment
Principle of recording and reflection factor and
degree of modulation at unrecorded/recorded position
5-2) Characteristics of light absorption spectra
relating to "L-H" recording film in the present
embodiment:
Condition for setting maximum absorption
wavelength ^max write' value of ^1495 and a value of
Ah405
5-3) Anion portion: Azo metal complex + cation
portion: Dye
5-4) Use of "copper" as azo metal complex + main
metal:
Light absorption spectra after recorded is widen
in a "H-L" recording film, and is narrowed in a "L-H"
recording film.
Upper limit value of maximum absorption wavelength
change amount before and after recording:
A maximum absorption wavelength change amount
before and after recording is small, and absorbance at
a maximum absorption wavelength changes.
Chapter 6:Description Relating to Pre-groove
shape/pre-pit shape in coating type organic dye
recording film and on light reflection layer interface
6-1) Light reflection layer (material and
thickness) :
Thickness range and passivation structure ...
Principle of recording and countermeasures against
degradation (Signal is degraded more easily than
substrate deformation or than cavity)
6-2) Description relating to pre-pit shape in
coating type organic dye recording film and on light
reflection layer interface:
Advantageous effect achieved by widening track
pitch/channel bit pitch in system lead-in area:
Reproduction signal amplitude value and resolution
in system lead-in area:
Rule on step amount at land portion and pre-pit
portion in light reflection layer 4-2:
6-3) Description relating to pre-groove shape in
coating type organic dye recording film and on light
reflection layer interface:
Rule on step amount at land portion and pre-groove
portion in light reflection layer 4-2:
Push-pull signal amplitude range:
Wobble signal amplitude range (combination with
wobble modulation system)
Chapter 7: Description of First Next-Generation
Optical Disk: HD DVD System (Hereinafter, Referred to
as H Format):
Principle of recording and countermeasure against
reproduction signal degradation (Signal is degraded
more easily than substrate deformation or than cavity):
Error Correction Code (ECC) structure, PRML
(Partial Response Maximum Likelihood) System:
Relationship between a wide flat area in the
groove and wobble address format.
In the write-once recording, overwriting is
carried out in a VFO area which is non-data area.
Influence of DC component change in overwrite area
is reduced. In particular, advantageous effect on "LH"
recording film is significant.
Chapter 8: Description of Second Next-Generation
Optical Disk: B format
Principle of recording and countermeasures against
reproduction signal degradation (Signal is degraded
more easily than substrate deformation or cavity).
Relationship between a wide flat area in the
groove and wobble address format
In the write-once recording, overwriting is
carried out in a VFO area which is a non-data area.
Influence of DC component change in overwrite area
is reduced. In particular, advantageous effect in "LH"
recording film is significant.
Now, a description of the present embodiment will
be given here.
Chapter 0:Description of Relationship between Use
Wavelength and the Present Embodiment
As a write-once type optical disk obtained by
using an organic dye material for a recording medium,
there has been commercially available a CD-R disk using
a recording/reproducing laser light source wavelength
of 780 nm and a DVD-R disk using a
recording/reproducing laser light beam wavelength of
650 nm. Further, in a next-generation write-once type
information storage medium having achieved high
density, it is proposed that a laser light source
wavelength for recording or reproducing, which is close
to 405 nm (namely, in the range of 355 nm to 455 nm),
is used in either of H format (Dl) and B format (D2) of
FIG. 1 described later. In a write-once type
information storage medium using an organic dye
material, recording/reproducing characteristics
sensitively changes due to a slight change of a light
source wavelength. In principle, density is increased
in inverse proportion to a square of a laser light
source wavelength for recording/reproducing, and thus,
it is desirable that a shorter laser light source
wavelength be used for recording/reproducing. However,
for the above described reason, an organic dye material
utilized for a CD-R disk or a DVD-R disk cannot be used
as a write-once type information storage medium for
405 nm. Moreover, because 405 nm is close to an
ultraviolet ray wavelength, there can easily occur a
disadvantage that a recording material "which can be
easily recorded with a light beam of 405 nm", is easily
changed in characteristics due to ultraviolet ray
irradiation, lacking a long period stability.
Characteristics are significantly different from each
other depending on organic dye materials to be used,
and thus, it is difficult to determine the
characteristics of these dye materials in general. As
an example, the foregoing characteristics will be
described by way of a specific wavelength. With
respect to an organic dye recording material optimized
with a light beam of 650 nm in wavelength, the light to
be used becomes shorter than 620 nm,
recording/reproducing characteristics significantly
change. Therefore, in the case where a
recording/reproducing operation is carried out with a
light beam which is shorter than 620 nm in wavelength,
there is a need for new development of an organic dye
material which is optimal to a light source wavelength
of recording light or reproducing light. An organic
dye material of which recording can be easily carried
out with a light beam shorter than 530 nm in wavelength
easily causes characteristic degradation due to
ultraviolet ray irradiation, lacking long period
stability. In the present embodiment, a description
will be given with respect to an embodiment relevant to
an organic recording material suitable to use in close
to 405 nm. Namely, a description will be given with
respect to an embodiment relating to an organic
recording material which can be stably used in the
range of 355 nm to 455 nm in consideration of a
fluctuation of a light emitting wavelength which
depends on manufacturers of semiconductor laser light
sources. That is, the scope of the present embodiment
corresponds to a light beam which is adapted to a light
source of 620 nm in wavelength, and desirably, which is
shorter than 530 nm in wavelength (ranging from 355 nm
to 455 nm in a definition in the narrowest range).
In addition, the optical recording sensitivity due
to light absorption spectra of an organic dye material
is also influenced by a recording wavelength. An
organic dye material suitable for long period stability
is easily reduced in light absorbance relevant to a
light beam which is shorter than 620 nm in wavelength.
In particular, the light absorbance is significantly
lowered with respect to a light beam which is shorter
than 620 nm in wavelength, and in particular, is
drastically reduced with respect to a light beam which
is shorter than 530 nm in wavelength. Therefore, in
the case where recording is carried out with a laser
light beam ranging from 355 nm to 455 nm in wavelength,
which is the severest condition, recording sensitivity
is impaired because the light absorbance is low, and
there is a need for a new design employing a new
principle of recording as shown in the present
embodiment.
The size of a focusing spot used for recording or
reproducing application is reduced in proportion to a
wavelength of a light beam to be used. Therefore, from
only a standpoint of the focusing spot size, in the
case where a wavelength is reduced to the above
described value, an attempt is made to reduce a track
pitch or channel bit length by a wavelength component
with respect to a current DVD-R disk (use wavelength:
650 ran) which is a conventional technique. However, as
described later in "3-2-A] Scope requiring application
of technique according to the present embodiment", as
long as a principle of recording in a conventional
write-once type information storage medium such as a
DVD-R disk is used, there is a problem that a track
pitch or a channel bit length cannot be reduced. A
track pitch or a channel bit length can be reduced in
proportion to the above described wavelength by
utilizing a technique devised in the present embodiment
described below.
Chapter 1: Description of Combination of
Constituent Elements of Information Storage Medium in
the Present Embodiment
In the present embodiment, there exists a great
technical feature in that an organic recording medium
material (organic dye material) adapted to a light
source of 620 nm or less in wavelength has been
devised. Such an organic recording medium (organic dye
material) has a unique characteristic (Low to High
characteristic) that a light reflection factor
increases in a recording mark, which does not exist in
a conventional CD-R disk or a DVD-R disk. Therefore, a
technical feature of the present embodiment and a novel
effect attained thereby occurs in a structure,
dimensions, or format (information recording format)
combination of the information storage medium which
produces more effectively the characteristics of the
organic recording material (organic dye materials)
shown in the present embodiment. FIG. 1 shows a
combination, which produces a new technical feature and
advantageous effect in the present embodiment. That is
the information storage medium in the present
embodiment has the following constituent elements:
A] an organic dye recording film;
B] a pre-format (such as pre-groove
shape/dimensions or pre-pit shape/dimensions);
C] a wobble condition (such as wobble modulation
method and wobble change shape, wobble amplitude, and
wobble allocating method); and
D] a format (such as format for recording data
which is to be recorded or which has been recorded in
advance in information storage medium).
Specific embodiments of constituent elements
correspond to the contents described in each column of
FIG. 1. A technical feature and a unique advantageous
effect of the present embodiment occur in combination
of the specific embodiments of the constituent elements
shown in FIG. 1. Hereinafter, a description will be
given with respect to a combination state of individual
embodiments at a stage of explaining the embodiments.
With respect to constituent elements, which do not
specify a combination, it denotes that the following
characteristics are employed:
A5) an arbitrary coating recording film;
B3) an arbitrary groove shape and an arbitrary pit
shape;
C4) an arbitrary modulation system;
C6) an arbitrary amplitude amount; and
D4) an arbitrary recording method and a format in
a write-once medium.
Chapter 2: Description of Difference in
reproduction signal between Phase Change Recording Film
and Organic Dye Recording Film
2-1) Difference in Principle of
Recording/Recording Film and Difference in Basic
Concept Relating to Generation of Reproduction Signal
FIG. 2A shows a standard phase change recording
film structure (mainly used for a rewritable-type
information storage medium), and FIG. 2B shows a
standard organic dye recording film structure (mainly
used for a write-once type information storage medium)
In the description of the present embodiment, a whole
recording film structure excluding transparent
substrates 2-1 and 2-2 shown in FIGS. 2A and 2B
(including light reflection layers 4-1 and 4-2) is
defined as a "recording film", and is discriminated
from recording layers 3-1 and 3-2 in which a recording
material is disposed. With respect to a recording
material using a phase change, in general, an optical
characteristic change amount in a recorded area (in a
recording mark) and an unrecorded area (out of a
recording mark) is small, and thus, there is employed
an enhancement structure for enhancing a relative
change rate of a reproduction signal. Therefore, in a
phase change recording film structure, as shown in
FIG. 2A, an undercoat intermediate layer 5 is disposed
between the transparent substrate 2-1 and a phase
change type recording layer 3-1, and an upper
intermediate layer 6 is disposed between the light
reflection layer 4-2 and the phase change type
recording layer 3-1. In the invention, as a material
for the transparent substrates 2-1 and 2-2, there is
employed a polycarbonate PC or an acrylic PMMA (poly
methyl methacrylate) which is a transparent plastic
material. A center wavelength of a laser light beam 7
used in the present embodiment is 405 nm, and
refractive index r\2i, 22 tne polycarbonate PC at
this wavelength is close to 1.62. Standard refractive
index ni and absorption coefficient ki in 405 nm at
GeSbTe (germanium antimony tellurium) which is most
generally used as a phase change type recording
material are ni =? 1.5 and k-i =? 2.5 in a crystalline
area, whereas they are ni = 2.5 and ki =? 1.8 in an
amorphous area. Thus, a refractive index (in the
amorphous area) of a phase change type recording medium
is different from a refractive index of the transparent
substrate 2-1, and reflection of a laser light beam 7
on an interface between the layers is easily occurred
in a phase change recording film structure. As
described above, for the reasons why (1) a phase change
recording film structure takes an enhancement
structure; and (2) a refractive index difference
between the layers is great or the like, a light
reflection amount change at the time of reproduction
from a recording mark recorded in a phase change
recording film (a differential value of a light
reflection amount from a recording mark and a light
reflection amount from an unrecorded area) can be
obtained as an interference result of multiple
reflection light beams generated on an interface
between the undercoat intermediate layer 5, the
recording layer 3-1, the upper intermediate layer 6,
and the light reflection layer 4-2. In FIG. 2A,
although the laser light beam 7 is apparently reflected
on an interface between the undercoat intermediate
layer 5 and the recording layer 3-1, an interface
between the recording layer 3-1 and the upper
intermediate layer 6, and an interface between the
upper intermediate layer 6 and the light reflection
layer 4-2, in actuality, a reflection light amount
change is obtained as an interference result between a
plurality of multiple reflection light beams.
In contrast, an organic dye recording film
structure takes a very simple laminate structure made
of an organic dye recording layer 3-2 and a light
reflection layer 4-2. An information storage medium
(optical disk) using this organic dye recording film is
called a write-once type information storage medium,
which enables only one time of recording. However,
unlike a rewritable-type information storage medium
using the phase change recording medium, this medium
cannot carry out an erasing process or a rewriting
process of information which has been recorded once. A
refractive index at 405 nm of a general organic dye
recording material is often close to n2 1-4 (n32 =
1.4 to 1.9 in the refractive index range at 405 nm of a
variety of organic dye recording materials) and an
absorption coefficient is often close to k2 0-2
0.1 to 0.2 in the absorption coefficient range
at 405 nm of a variety of organic dye recording
materials). Because a refractive index difference
between the organic dye recording material and the
transparent substrate 2-2 is small, there hardly occurs
a light reflection amount on an interface between the
recording layer 3-2 and the transparent substrate 2-2.
Therefore, an optical reproduction principle of an
organic color recording film (reason why a reflection
light amount change occurs) is not "multiple
interference" in a phase change recording film, and a
main factor is a "light amount loss (including
interference) midway of an optical path with respect to
the laser light beam 7 which comes back after being
reflected in the light reflection layer 4-2". Specific
reasons which cause a light amount loss midway of an
optical path include an "interference phenomenon due to
a phase difference partially caused in the laser light
7" or an "optical absorption phenomenon in the
recording layer 3-2". The light reflection factor of
the organic dye recording film in an unrecorded area on
a mirror surface on which a pre-groove or a pre-pit
does not exist is featured to be simply obtained by a
value obtained by subtracting an optical absorption
amount when the recording layer 3-2 is passed from the
light reflection factor of the laser light beam 7 in
the light reflection layer 4-2. As described above,
this film is different from a phase change recording
film whose light reflection factor is obtained by
calculation of "multiple interference".
First, a description will be given with respect to
a principle of recording, which is used in a current
DVD-R disk as a conventional technique. In the current
DVD-R disk, when a recording film is irradiated with
the laser light beam 7, the recording layer 3-2 locally
absorbs energy of the laser light beam 7, and becomes
hot. If a specific temperature is exceeded, the
transparent substrate 2-2 is locally deformed.
Although a mechanism, which induces deformation of the
transparent substrate 2-2, is different depending on
manufacturers of DVD-R disks, it is said that this
mechanism is caused by:
1) local plastic deformation of the transparent
substrate 2-2 due to gasification energy of the
recording layer 3-2; and
2) transmission of a heat from the recording layer
3-2 to the transparent substrate 2-2 and local plastic
deformation of the transparent substrate 2-2 due to the
heat.
If the transparent substrate 2-2 is locally
plastically deformed, there changes an optical distance
of the laser light beam 7 reflected in the light
reflection layer 4-2 through the transparent substrate
2-2, the laser light beam 7 coming back through the
transparent substrate 2-2 again. A phase difference
occurs between the laser light beam 7 from a recording
mark, the laser light beam coming back through a
portion of the locally plastically deformed transparent
substrate 2-2, and a laser light beam 7 from the
periphery of the recording mark, the laser light beam
coming back through a portion of a transparent
substrate 2-2 which is not deformed, and thus, a light
amount change of reflection light beam occurs due to
interference between these light beams. In addition,
in particular, in the case where the above described
mechanism of (1) has occurred, a change of a
substantial refractive index n^2 produced by cavitation
of the inside of the recording mark in the recording
layer 3-2 due to gasification (evaporation), or
alternatively, a change of a refractive index n2
produced due to thermal decomposition of an organic dye
recording material in the recording mark, also
contributes to the above described occurrence of a
phase difference. In the current DVD-R disk, until the
transparent substrate 2-2 is locally deformed, there is
a need for the recording layer 3-2 becoming hot (i.e.,
at a gasification temperature of the recording layer
3-2 in the above described mechanism of (1) or at an
internal temperature of the recording layer 3-2
required for plastically reforming the transparent
substrate 2-2 in the mechanism of (2)) or there is a
need for a part of the recording layer 3-2 becoming hot
in order to cause thermal decomposition or gasification
(evaporation). In order to form a recording mark,
there is a need for large amount of power of the laser
light beam 7.
In order to form the recording mark, there is a
necessity that the recording layer 3-2 can absorb
energy of the laser light beam 7 at a first stage. The
light absorption spectra in the recording layer 3-2
influence the recording sensitivity of an organic dye
recording film. A principle of light absorption in an
organic dye recording material which forms the
recording layer 3-2 will be described with reference to
(A3) of the present embodiment.
FIG. 3 shows a specific structural formula of the
specific contents "(A3) azo metal complex + Cu" of the
constituent elements of the information storage medium
shown in FIG. 1. A circular periphery area around a
center metal M of the azo metal complex shown in FIG. 3
is obtained as a light emitting area 8. When a laser
light beam 7 passes through this light emitting area 8,
local electrons in this light emitting area 8 resonate
to an electric field change of the laser light beam 7,
and absorbs energy of the laser light beam 7. A value
converted to a wavelength of the laser light beam with
respect to a frequency of an electric field change at
which these local electrons resonate most and easily
absorbs the energy is called a maximum absorption
wavelength, and is represented by A,max. As a range of
the light emitting area 8 (resonation range) as shown
in FIG. 3 increases, the maximum absorption wavelength
^max is shifted to the long wavelength side. In
addition, in FIG. 3, the localization range of local
electrons around the center metal M (how large the
center metal M can attract the local electrons to the
vicinity of the center) is changed by changing atoms of
the center metal M, and the value of the maximum
absorption wavelength A,max changes.
Although it can be predicted that the light
absorption spectra of the organic dye recording
material in the case where there exists only one light
emitting area 8 which is absolute 0 degree at a
temperature and high in purity draws narrow linear
spectra in close to a maximum absorption wavelength
Xmax, the light absorption spectra of a general organic
recording material including impurities at a normal
temperature, and further, including a plurality of
light absorption areas exhibit a wide light absorption
characteristic with respect to a wavelength of a light
beam around the maximum absorption wavelength X,max.
FIG. 4 shows an example of light absorption
spectra of an organic dye recording material used for a
current DVD-R disk. In FIG. 4, a wavelength of a light
beam to be irradiated with respect to an organic dye
recording film formed by coating an organic dye
recording material is taken on a horizontal axis, and
absorbance obtained when an organic dye recording film
is irradiated with a light beam having a respective
wavelength is taken on a vertical axis. The absorbance
used here is a value obtained by entering a laser light
beam having incident intensity lo from the side of the
transparent substrate 2-2 with respect to a state in
which a write-once type information storage medium has
been completed (or alternatively, a state in which the
recording layer 3-2 has been merely formed on the
transparent substrate 2-2 (a state that precedes
forming of the optical reflection layer 4-2 with
respect to a structure of FIG. 2B)), and then,
measuring reflected laser light intensity Ir (light
intensity It of the laser light beam transmitted from
the side of the recording layer 3-2). The absorbance
Ar (At) is represented by:
Ar = -Iog10(lr/Io) (A-l)
Ar = -logio(It/Io) (A-2)
Unless otherwise specified, although a description
will be given assuming that the absorbance denotes
absorbance Ar of a reflection shape expressed by
formula (A-l), it is possible to define absorbance At
of a transmission shape expressed by formula (A-2)
without being limited thereto in the present
embodiment. In the embodiment shown in FIG. 4, there
exist a plurality of light absorption areas, each of
which includes the light emitting area 8, and thus,
there exist a plurality of positions at which the
absorbance becomes maximal. In this case, there exist
a plurality of maximum absorption wavelength Xmax when
the absorbance takes a maximum value. A wavelength of
the recording laser light in the current DVD-R disk is
set to 650 nm. In the case where there exist a
plurality of the maximum absorption wavelengths
the present embodiment, a value of the maximum
absorption wavelength ^max which is the closest to the
wavelength of the recording laser light beam becomes
important. Therefore, only in the description of the
present embodiment, the value of the maximum absorption
wavelength A,max set at a position which is the closest
to the wavelength of the recording laser light beam is
defined as "A,max write"; and is discriminated from
another Xmax (Xmax 0)•
2-2) Difference of light reflection layer shape in
pre-pit/pre-groove area
FIGS. 5A and 5B each show a comparison in shape
when a recording film is formed in a pre-pit area or a
pre-groove area 10. FIG. 5A shows a shape relevant to
a phase change recording film. In the case of forming
any of the undercoat intermediate layer 5, the
recording layer 3-1, the upper intermediate layer 6,
and the light reflection layer 4-1 as well, any of
methods of sputtering vapor deposition, vacuum vapor
deposition, or ion plating is used in vacuum. As a
result, in all of the layers, irregularities of the
transparent substrate 2-1 are duplicated comparatively
faithfully. For example, in the case where a sectional
shape in the pre-pit area or pre-groove area 10 of the
transparent substrate 2-1 is rectangular or
trapezoidal, the sectional shape of the recording layer
3-1 and the light reflection layer 4-1 each is also
rectangular or trapezoidal.
FIG. 5B shows a general recording film sectional
shape of a current DVD-R disk which is a conventional
technique as a recording film in the case where an
organic dye recording film has been used. In this
case, as a method for forming the recording film 3-2,
there is used a method called spin coating (or spinner
coating) which is completely different from that shown
in FIG. 5A. The spin coating used here denotes a
method for dissolving in an organic solvent an organic
dye recording material which forms the recording layer
3-2; applying a coating onto the transparent substrate
2-2; followed by rotating the transparent substrate 2-2
at a high speed to spread a coating agent to the outer
periphery side of the transparent substrate 2-2 by a
centrifugal force; and gasifying the organic solvent,
thereby forming the recording layer 3-2. Using this
method, a process for coating the organic solvent is
used, and thus, a surface of the recording layer 3-2
(an interface with the light reflection layer 2-2) is
easily flattened. As a result, the sectional shape on
the interface between the light reflection layer 2-2
and the recording layer 3-2 is obtained as a shape
which is different from the shape of the surface of the
transparent substrate 2-2 (an interface between the
transparent substrate 2-2 and the recording layer 3-2).
For example, in a pre-groove area in which the
sectional shape of the surface of the transparent
substrate 2-2 (an interface between the transparent
substrate 2-2 and the recording layer 3-2) is
rectangular or trapezoidal, the sectional shape on the
interface between the light reflection layer 2-2 and
the recording layer 3-2 is formed in a substantially
V-shaped groove shape. In a pre-pit area, the above
sectional shape is formed in a substantially conical
side surface shape. Further, at the time of spin
coating, an organic solvent is easily collected at a
recessed portion, and thus, the thickness Dg of the
recording layer 3-2 in the pre-pit area or pre-groove
area 10 (i.e., a distance from a bottom surface of the
pre-pit area or pre-groove area to a position at which
an interface relevant to the light reflection layer 2-2
becomes the lowest) is larger than the thickness Dl in
a land area 12 (Dg Dl). As a result, an amount of
irregularities on an interface between the transparent
substrate 2-2 and the recording area 3-2 in the pre-pit
area or pre-groove area 10 becomes substantially
smaller than an amount of irregularities on the
transparent substrate 2-2 and the recording layer 3-2.
As described above, the shape of irregularities on
the interface between the light reflection layer 2-2
and the recording layer 3-2 becomes blunt and an amount
of irregularities becomes significantly small. Thus,
in the case where the shape and dimensions of
irregularities on a surface of the transparent
substrate 2 (pre-pit area or pre-groove area 10) are
equal to each other depending on a difference in method
for forming a recording film, the diffraction intensity
of the reflection light beam from the organic dye
recording film at the time of laser light irradiation
is degraded more significantly than the diffraction
intensity of the reflection light beam from the phase
change recording film. As a result, in the case where
the shape and dimensions of irregularities on the
surface of the transparent substrate 2 (pre-pit area or
pre-groove area 10) are equal to each other, as
compared with use of the phase change recording film,
use of the conventional organic dye recording film is
disadvantageously featured in that:
1) a degree of modulation of a light reproduction
signal from the pre-pit area is small, and signal
reproduction reliability from the pre-pit area is poor;
2) a sufficiently large track shift detecting
signal is hardly obtained in accordance with a pushpull
technique from the pre-groove area; and
3) a sufficient large wobble detecting signal is
hardly obtained in the case where wobbling occurs in
the pre-groove area.
In addition, in a DVD-R disk, specific information
such as address information is recorded in a small
irregular (pit) shape in a land area, and thus, a width
Wl of the land area 12 is larger than a width Wg of the
pre-pit area or pre-groove area 10 (Wg Wl).
Chapter 3: Description of Characteristics of
Organic Dye Recording Film in the Present Embodiment
3-1) Problem(s) relevant to achievement of high
density in write-once type recording film (DVD-R) using
conventional organic dye material
As has been described in "2-1) Difference in
recording principle/recording film structure and
difference in basic concept relating to generation of
reproducing signal", a general principle of recording
of a current DVD-R and CD-R, which is a write-once type
information storage medium using a conventional organic
dye material includes "local plastic deformation of
transparent substrate 2-2" or "local thermal
decomposition or "gasification" in recording layer
3-2". FIGS. 6A and 6B each show a plastic deformation
state of a specific transparent substrate 2-2 at a
position of a recording mark 9 in a write-once type
information storage medium using a conventional organic
dye material. There exist two types of typical plastic
deformation states. There are two cases, i.e., a case
in which, as shown in FIG. 6A, a depth of a bottom
surface 14 of a pre-groove area at the position of the
recording mark 9 (an amount of step relevant to an
adjacent land area 12) is different from a depth of a
bottom surface of a pre-groove area 11 in an unrecorded
area (in the example shown in FIG. 6A, the depth of the
bottom surface 14 in the pre-groove area at the
position of the recording mark 9 is shallower than that
in the unrecorded area); and a case in which, as shown
in FIG. 6B, a bottom surface 14 in a pre-groove area at
the position of the recording mark 9 is distorted and
is slightly curved (the flatness of the bottom surface
14 is distorted: In the example shown in FIG. 6B, the
bottom surface 14 in the pre-groove area at the
position of the recording mark 9 is slightly curved
toward the lower side). Both of these cases are
featured in that a plastic deformation range of the
transparent substrate 2-2 at the position of the
recording mark 9 covers a wide range. In the current
DVD-R disk which is a conventional technique, a track
pitch is 0.74 jam, and a channel bit length is 0.133 )im.
In the case of a large value of this degree, even if
the plastic deformation range of the transparent
substrate 2-2 at the position of the recording mark 9
covers a wide range, comparatively stable recording and
reproducing processes can be carried out.
However, if the track pitch is narrower than
0.74 fj,m described above, the plastic deformation range
of the transparent substrate 2-2 at the position of the
recording mark 9 covers a wide range, and thus, the
adjacent tracks are adversely affected, and the
recording mark 9 of the existing adjacent track is
substantially erased (cannot be reproduced) due to a
"cross-write" or overwrite in which the recording mark
9 widens to the adjacent tracks. In addition, in a
direction (circumferential direction) along the tracks,
if the channel bit length is narrower than 0.133 (im,
there occurs a problem that inter-code interference
appears; an error rate at the time of reproduction
significantly increases; and the reliability of
reproduction is lowered.
3-2) Description of basic characteristics common
to organic dye recording film in the present embodiment
3-2-A] Range requiring application of technique
according to the present embodiment
As shown in FIGS. 6A and 6B, in a conventional
write-once type information storage medium including
plastic deformation of the transparent substrate 2-2 or
local thermal decomposition or gasification phenomenon
in the recording film 3-2, a description will be given
below with respect to what degree of track pitch is
narrowed when an adverse affect appears or what degree
of channel pit length is narrowed when an adverse
effect appears and a result obtained after technical
discussion has been carried out with respect to a
reason for such an adverse effect. A range in which an
adverse effect starts appearing in the case of
utilizing the conventional principle of recording
indicates a range (suitable for the achievement of high
density) in which advantageous effect is attained due
to a novel principle of recording shown in the present
embodiment.
1) Condition of thickness Dg of recording
layer 3-2
When an attempt is made to carry out thermal
analysis in order to theoretically identify a lower
limit value of an allowable channel bit length or a
lower limit value of allowable track pitch, a range of
the thickness Dg of a recording layer 3-2 which can be
substantially thermally analyzed becomes important. In
a conventional write-once type information storage
medium (CD-R or DVD-R) including plastic deformation of
the transparent substrate 2-2 as shown in FIGS. 6A and
6B, with respect to a change of light reflection amount
in the case where an information reproduction focusing
spot is provided in the recording mark 8 and in the
case where the spot is in an unrecorded area of the
recording layer 3-2, the largest factor is "an
interference effect due to a difference in optical
distance in the recording mark 9 and in unrecorded
area". In addition, a difference in its optical
difference is mainly caused by "a change of the
thickness Dg of a physical recording layer 3-2 due to
plastic deformation of the transparent substrate 2-2 (a
physical distance from an interface between the
transparent substrate 2-2 and the recording layer 3-2
to an interface between the recording layer 3-2 and a
light reflection layer 4-2) and "a change of refractive
index n32 °f the recording layer 3-2 in the recording
mark 9". Therefore, in order to obtain a sufficient
reproduction signal (change of light reflection amount)
between the recording mark 9 and the unrecorded area,
when a wavelength in vacuum of laser light beam is
defined as X, it is necessary for the value of the
thickness 3-2 in the unrecorded area has a size to some
extent as compared with X/n32. If not, a difference
(phase difference) in optical distance between the
recording mark 9 and the unrecorded area does not
appear, and light interference effect becomes small.
In reality, a minimum condition:
Dg A./8n32 (1)
must be met, and desirably, a condition that:
Dg X/4n32 (2)
At a time point of current discussion, the
vicinity of A, = 405 nm is assumed. A value of
refractive index n2 °f an organic dye recording
material at 405 nm ranges from 1.3 to 2.0. Therefore,
as a result of substituting n2 = 2.0 in formula (1),
it is conditionally mandatory that a value of the
thickness Dg of the recording layer 3-2 is:
Dg 25 nm (3)
Here, discussion is made with respect to a
condition when an organic dye recording layer of a
conventional write-once type information storage medium
(CD-R or DVD-R) including plastic deformation of the
transparent substrate 2-2 has been associated with a
light beam of 405 nm. As described later, in the
present embodiment, although a description is given
with respect to a case in which plastic deformation of
the transparent substrate 2-2 does not occur and a
change of an absorption coefficient k2 is a main
factor of a principle of recording, it is necessary to
carry out track shift detection by using a DPD
(Differential Phase Detection) technique from the
recording mark 9, and thus, in reality, the change of
the refractive index n32 is caused in the recording
mark 9. Therefore, the condition for formula (3)
becomes a condition, which should be met, in the
present embodiment in which plastic deformation of the
transparent substrate 2-2 does not occur.
From another point of view as well, the range of
the thickness Dg can be specified. In the case of a
phase change recording film shown in FIG. 5A, when a
refractive index of the transparent substrate is r\2i, a
step amount between a pre-pit area and a land area is
X/(8n2i) when the largest track shift detection signal
is obtained by using a push-pull technique. However,
in the case of an organic dye recording film shown in
FIG. 5B, as described previously, the shape on an
interface between the recording layer 3-2 and the light
reflection layer 4-2 becomes blunt, and a step amount
becomes small. Thus, it is necessary to increase a
step amount between a pre-pit area and a land area on
the transparent substrate 2-2 more significantly than
X/(8n22) For example, the refractive index at 405 nm
in the case where polycarbonate has been used as a
material for the transparent substrate 2-2 is
n22 1-62, and thus, it is necessary to increase a
step amount between the pre-pit area and the land area
more significantly than 31 nm. In the case of using a
spin coating technique, if the thickness Dg of the
recording layer 3-2 in the pre-groove area is greater
than a step amount between the pre-pit area and the
land area on the transparent substrate 2-2, there is a
danger that thickness Dl of the recording layer 3-2 in
a land area 12 is eliminated. Therefore, from the
above described discussion result, it is necessary to
meet a condition that:
Dg ^ 31 nm (4)
The condition for formula (4) is also a condition,
which should be met in the present embodiment in which
plastic deformation of the transparent substrate 2-2
does not occur. Although conditions for the lower
limit values have been shown in formulas (3) and (4),
the value Dg = 60 nm obtained by substituting n2 =
1.8 for an equal sign portion in formula (2) has been
utilized as the thickness Dg of the recording layer 3-2
used for thermal analysis.
Then, assuming polycarbonate used as a standard
material of the transparent substrate 2-2, 150°C which
is a glass transition temperature of polycarbonate has
been set as an estimate value of a thermal deformation
temperature at the side of the transparent substrate
2-2. For discussion using thermal analysis, a value of
k32 = 0.1 to 0.2 has been assumed as a value of an
absorption coefficient of the organic dye recording
film 3-2 at 405 nm. Further, discussion has been made
with respect to a case in which an NA value of a
focusing objective lens and an incident light intensity
distribution when an objective lens is passed is NA =
60 and H format ((D1):NA = 0.65 in FIG. 1) and B format
((D2):NA = 0.85 in FIG. 1) which is assumed condition
in a conventional DVD-R format.
2) Condition for lower limit value of channel bit
length
A check has been made for a lengthwise change in a
direction along a track of an area reaching a thermal
deformation temperature at the side of a transparent
substrate 2-2 which comes into contact with a recording
layer 3-2 when recording power has been changed.
Discussion has been made with respect to a lower limit
value of an allowable channel bit length considering a
window margin at the time of reproduction. As a
result, if the channel bit length is slightly lower
than 105 nm, it is considered that a lengthwise change
in a direction along a track in an area which reaches
the thermal deformation temperature at the side of the
transparent substrate 2-2 occurs according to the
slight change of recording power, and a sufficient
window margin cannot be obtained. On discussion of
thermal analysis, an analogous tendency is shown in the
case where the NA value is any one of 0.60, 0.65, and
0.85. Although a focusing spot size is changed by
changing the NA value, a possibility cause is believed
to be that a thermal spreading range is wide (a
gradient of a temperature distribution at the side of
the transparent substrate 2-2 which comes into contact
with the recording layer 3-2) is comparatively gentle).
In the above thermal analysis, the temperature
distribution at the side of the transparent substrate
2-2 which comes into contact with the recording layer
3-2 is discussed, and thus, an effect of the thickness
Dg of the recording layer 3-2 does not appear.
Further, in the case where a shape change of the
transparent substrate 3-3 shown in FIGS. 6A and 6B
occurs, a boundary position of a substrate deformation
area blurs (is ambiguous), and thus, a window margin is
lowered more significantly. When a sectional shape of
an area in which the recording mark 9 is formed is
observed by an electron microscope, it is believed that
a blurring amount of the boundary position of the
substrate deformation area increases as the value of
the thickness Dg of the recording layer 3-2 increases.
With respect to the effect of the thermal deformation
area length due to the above recording power change, in
consideration of the blurring of the boundary position
of this substrate deformation area, it is considered
necessary that the lower limit value of the channel bit
length allowed for allocation of a sufficient window
margin is in order of two times of the thickness Dg of
the recording layer 3-2, and it is desirable that the
lower limit value is greater than 120 nm.
In the foregoing, a description has been
principally given with respect to discussion using
thermal analysis in the case where thermal deformation
of the transparent substrate 2-2 occurs. There also
exists a case in which plastic deformation of the
transparent substrate 2-2 is very small as another
orinciple of recording (mechanism of forming the
recording mark 9) in a conventional write-once type
information storage medium (CD-R or DVD-R) and thermal
deformation or gasification (evaporation) of the
organic dye recording material in the recording layer
3-2 mainly occurs. Thus, an additional description
rfill be given with respect to such a case. Although
the gasification (evaporation) temperature of the
organic dye recording material is different depending
on the type of the organic dye material, in general,
the temperature ranges 220°C to 370°C, and a thermal
decomposition temperature is lower than this range.
Although a glass transition temperature 150°C of a
polycarbonate resin has been presumed as an arrival
temperature at the time of substrate deformation in the
above discussion, a temperature difference between
150°C and 220°C is small, and, when the transparent
substrate 2-2 reaches 150°C, the inside of the
recording layer 3-2 exceeds 220°C. Therefore, although
there exists an exception depending on the type of the
organic recording material, even in the case where
plastic deformation of the transparent substrate 2-2 is
very small and thermal decomposition or gasification
(evaporation) of the organic dye recording material in
the recording layer mainly occurs, there is obtained a
result which is substantially identical to the above
discussion result.
When the discussion result relating to the above
channel bit length is summarized, in the conventional
write-once type information storage medium (CD-R or
DVD-R) including plastic deformation of the transparent
substrate 2-2, it is considered that, when a channel
bit length is narrower than 120 nm, the lowering of a
window margin occurs, and further, if the length is
smaller than 105 nm, stable reproduction becomes
difficult. That is, when the channel bit is smaller
than 120 nm (105 nm), advantageous effect is attained
by using a novel principle of recording shown in the
present embodiment.
3) Condition for lower limit value of track
pitches
When a recording layer 3-2 is exposed at recording
power, energy is absorbed in the recording layer 3-2,
and a high temperature is obtained. In a conventional
write-once type information storage medium (CD-R or
DVD-R), it is necessary to absorb energy in the
recording layer 3-2 until the transparent substrate 3-2
has reached a thermal deformation temperature. A
temperature at which a structural change of the organic
dye recording material occurs in the recording layer
3-2 and a value of a refractive index r\2 or an
absorption coefficient k^2 starts its change is much
lower than an arrival temperature for the transparent
substrate 2-2 to start thermal deformation. Therefore,
the value of the refractive index 1132 or absorption
coefficient k^2 changes in a comparatively wide range
in the recording layer 3-2 at the periphery of a
recording mark 9, which is thermal deformed at the side
of the transparent substrate 2-2, and this change seems
to cause "cross-write" or "cross-erase" for the
adjacent tracks. It is possible to set a lower limit
value of track pitch in which "cross-write" or "crosserase"
does not occur with the width of an area which
reaches a temperature which changes the refractive
index n^2 or absorption coefficient k^2 i-n the
recording layer 3-2 when the transparent substrate 2-2
exceeds a thermal deformation temperature. From the
above point of view, it is considered that "crosswrite"
or "cross-erase" occurs in location in which the
track pitch is equal to or smaller than 500 ran.
Further, in consideration of an effect of warping or
inclination of an information storage medium or a
change of recording power (recording power margin), it
can be concluded difficult to set the track pitch to
600 nm or less in the conventional write-once type
information storage medium (CD-R or DVD-R) in which
energy is absorbed in the recording layer 3-2 until the
transparent substrate 2-2 has reached a thermal
deformation temperature.
As described above, even if the NA value is
changed from 0.60, 0.65, and then, to 0.85,
substantially similar tendency is shown because the
gradient of the temperature distribution in the
peripheral recording layer 3-2 when the transparent
substrate 2-2 has reached a thermal deformation
temperature at a center part is comparatively gentle,
and the thermal spread range is wide. In the case
where plastic deformation of the transparent substrate
2-2 is very small and thermal decomposition or
gasification (evaporation) of the organic dye recording
material in the recording layer 3-2 mainly occurs as
another principle of recording (mechanism of forming
the recording mark 9) in the conventional write-once
type information storage medium (CD-R or DVD-R), as has
been described in the section "(2) Condition for lower
limit value of channel bit", the value of track pitch
at which "cross-write" or "cross-erase" starts is
obtained as a substantially analogous result. For the
above described reason, advantageous effect is attained
by using a novel principle of recording shown in the
present embodiment when the track pitch is set to
600 nm (500 nm) or lower.
3-2-B] Basic characteristics common to organic dye
recording material in the invention
As described above, in the case where plastic
deformation of the transparent substrate 2-2 is very
small and thermal decomposition or gasification
(evaporation) of the organic dye recording material in
the recording layer 3-2 mainly occurs as another
principle of recording (mechanism of forming the
recording mark 9) in the conventional write-once type
information storage medium (CD-R or DVD-R), there
occurs a problem that a channel bit length or track
pitches cannot be narrowed because the inside of the
recording layer 3-2 or a surface of the transparent
substrate 2-2 reaches a high temperature at the time of
forming the recording mark 9. In order to solve the
above described problem, the present embodiment is
primarily featured in "inventive organic dye material"
in which "a local optical characteristic change in the
recording layer 3-2, which occurs at a comparatively
low temperature, is a principle of recording" and
"setting environment (recording film structure or
shape) in which the above principle of recording easily
occurs without causing a substrate deformation and
gasification (evaporation) in the recording layer 3-2.
Specific characteristics of the present embodiment can
be listed below.
a] Optical characteristic changing method inside
of recording layer 3-2
Chromogenic characteristic change
Change of light absorption sectional area due
to qualitative change of light emitting area 8 (FIG. 3)
or change of molar molecule light absorption
coefficient
The light emitting area 8 is partially destroyed
or the size of the light emitting area 8 changes,
whereby a substantial light absorption sectional area
changes. In this manner, an amplitude (absorbance) at
a position of changes in the recording mark
9 while a profile (characteristics) of light absorption
spectra (FIG. 4) itself is maintained.
Change of electronic structure (electron orbit)
relevant to electrons which contribute to a chromogenic
phenomenon
Change of light absorption spectra (FIG. 4)
based on discoloring action due to cutting of local
electron orbit (dissociation of local molecular
bonding) or change of dimensions or structure of light
emitting area 8 (FIG. 3)
Intra-molecular (inter-molecular) change of
orientation or array
Optical characteristic change based on
orientation change in azo metal complex shown in
FIG. 3, for example
Molecular structure change in molecule
For example, discussion is made with respect
to an organic dye material which causes either of
dissociation between anion portion and cation portion,
thermal decomposition of either of anion portion and
cation portion, and a tar phenomenon that a molecular
structure itself is destroyed, and carbon atoms are
precipitated (denaturing to black coal tar). As a
result, the refractive index n^2 or absorption
coefficient k^2 in the recording mark 9 is changed with
respect to an unrecorded area, enabling optical
reproduction.
P] Setting recording film structure or shape,
making it easy to stably cause an optical
characteristic change of [a] above:
The specific contents relating to this
technique will be described in detail in the section
"3-2-C] Ideal recording film structure which makes it
easy to cause a principle of recording shown in the
present embodiment" and subsequent.
y] Recording power is reduced in order to form
recording mark in a state in which inside of recording
layer or transparent substrate surface is comparatively
low at temperature
The optical characteristic change shown in [a]
above occurs at a temperature lower than a deformation
temperature of the transparent substrate 2-2 or a
gasification (evaporation) temperature in the recording
layer 3-2. Thus, the exposure amount (recording power)
at the time of recording is reduced to prevent the
deformation temperature from being exceeded on the
surface of the transparent substrate 2-2 or the
gasification (evaporation) temperature from being
exceeded in the recording layer 3-2. The contents will
be described later in detail in the section "3-3)
Recording characteristics common to organic dye
recording layer in the present embodiment". In
addition, in contrast, it becomes possible to determine
whether or not the optical characteristic change shown
in [a] above occurs by checking a value of the optimal
power at the time of recording.
8] Electron structure in a light emitting area is
stabilized, and structural decomposition relevant to
ultraviolet ray or reproduction light irradiation is
hardly generated
When ultraviolet ray is irradiated to the
recording layer 3-2 or reproduction light is irradiated
to the recording layer 3-2 at the time of reproduction,
a temperature size in the recording layer 3-2 occurs.
There is a request for a seemingly contradictory
performance that characteristic degradation relevant to
such a temperature rise is prevented and recording is
carried out at a temperature lower than a substrate
deformation temperature or a gasification (evaporation)
temperature in the recording layer 3-2. In the present
embodiment, the above described seemingly contradictory
performance is ensured by "stabilizing an electron
structure in a light emitting area". The specific
technical contents will be described in "Chapter 4
Specific Description of Embodiments of Organic Dye
Recording Film in the Present Embodiment".
e] Reliability of reproduction information is
improved for a case in which reproduction signal
degradation due to ultraviolet ray or reproduction
light irradiation occurs
In the present embodiment, although a
technical contrivance is made for "stabilizing an
electron structure in a light emitting area", the
reliability of the recording mark 9 formed in a
principle of recording shown in the present embodiment
may be principally lowered as compared with a local
cavity in the recording layer 3-2 generated due to
plastic deformation or gasification (evaporation) of
the surface of the transparent substrate 2-2. As
countermeasures against it, in the present embodiment,
advantageous effect that the high density and the
reliability of recording information are achieved at
the same time in combination with strong error
correction capability (novel ECC block structure), as
described later in "Chapter 7: Description of H Format"
and "Chapter 8: Description of B Format". Further, in
the present embodiment, PRML (Partial Response Maximum
Likelihood) technique is employed as a reproduction
method, as described in the section "4-2 Description of
reproducing circuit in the present embodiment", the
high density and the reliability of recording
information are achieved at the same time in
combination with an error correction technique at the
time of ML demodulation.
Among the specific characteristics of the above
described present embodiment, a description has been
given with respect to the fact that items [a] to [y]
are the contents of technical contrivance newly devised
in the present embodiment in order to achieve "narrow
track pitch" and "narrow channel bit length". In
addition, "narrow channel bit length" causes the
achievement of "reduction of minimum recording mark
length". The meanings (objects) of the present
embodiment relating to the remaining items [8] and [e]
will be described in detail. At the time of
reproduction in the H format in the present embodiment,
a passage speed (line speed) of a focusing spot of
light passing through the recording layer 3-2 is set to
6.61 m/s, and the line speed in the B format is set in
the range of 5.0 m/s to 10.2 m/s.
In any case, the line speed at the time of
reproduction in the present embodiment is equal to or
greater than 5 m/s. As shown in FIG. 31, a start
position of a data lead-in area DTLDI in the H format
is 47.6 mm in diameter. In view of the B format as
well, user data is recorded in location equal to or
greater than 45 mm in diameter. An inner periphery of
45 mm in diameter is 0.141 m, and thus, the rotation
frequency of an information storage medium when this
position is reproduced at a line speed of 5 m/s is
obtained as 35.4 rotations/s. Video image information
such as TV program is provided as one of the methods
utilizing a write-once type information storing medium
according to the present embodiment. For example, when
a user presses "pause (temporary stop) button" at the
reproduction of the user's recorded video image, a
reproduction focusing spot stays on a track of its
paused position. When the spot stops on the track of
the paused position, the user can start reproduction at
the paused position immediately after a "reproduction
start button" has been pressed. For example, after the
user has pressed a "pause (temporary stop) button", in
the case where a customer visits the user's home
immediately after the user has gone to toilet, there is
a case in which the pause button is left to have been
pressed for one hour while the user meets the customer.
The write-once type information storage medium makes
35.4 x 60 x 60 ^ 130,000 rotations for one hour, and
the focusing spot traces on the same track during this
period (130,000 repetitive playbacks). If the
recording layer 3-2 is degraded due to repetitive
playback and video image information cannot be
reproduced after this period, the user coming back one
hour later cannot see any portion of video image, and
thus, gets angry, and in the worst case, there is a
danger that the problem may be taken to court.
Therefore, a minimum condition that, if the recorded
video image information is not destroyed even if such a
pausing is left for one hour or longer (even if
continuous playback in the same track occurs), no video
image data is destroyed, requires to guarantee that at
least 100,000 repetitive playback occurs, no
reproduction degradation occurs. There is a rare case
in which a user repeats one-hour pausing (repetitive
playback) 10 times with respect to the same location in
a general use condition. Therefore, when it is
guaranteed that the write-once type information storage
medium according to the present embodiment desirably
makes 1,000,000 repetitive playbacks, no problem occurs
with use by the general user, and it is considered
sufficient to set to about 1,000,000 times the upper
limit value of the repetitive playback count as long as
the recording layer 3-2 is not degraded. If the upper
limit value of the repetitive playback count is set to
a value which significantly exceeds 1,000,000 times,
there occurs inconvenience that "recording sensitivity
is lowered" or "medium price increases".
In the case where the upper limit value of the
above repetitive reproduction count is guaranteed, a
reproduction power value becomes an important factor.
In the present embodiment, recording power is defined
in a range set in formulas (8) to (13). It is said
that a semiconductor laser beam is featured in that
continuous light irradiation is not stable in a value
equal to or smaller than 1/80 of the maximum use power.
Because the power, which is 1/80 of the maximum use
power, is in location in which light irradiation is
just started (mode initiation is started), mode hopping
is likely to occur. Therefore, at this light
irradiation power, the light reflected in the light
reflection layer 4-2 of the information storage medium
comes back to a semiconductor laser light source, there
occurs a "return light noise" featured in that the
light emission amount always changes. Accordingly, in
the present embodiment, the values of the reproduction
power is set below around the value which is 1/80 of
the value described at the right side of formula (12)
or formula (13):
[Optical reproduction power]
0.19 x (0.65/NA)2 x (V/6.6) (B-l)
[Optical reproduction power]
0.19 x (0.65/NA)2 x (V/6.6)1-2 (B-2)
In addition, the value of the optimal reproduction
power is restricted by a dynamic range of a power
monitoring optical detector. Although not shown in an
information recording/reproducing unit 141 of FIG. 11,
a recording/reproducing optical head exists. This
optical head incorporates an optical detector which
monitors a light emission amount of a semiconductor
laser light source. In the present embodiment, in
order to improve light irradiation precision of the
reproduction power at the time of reproduction, this
optical detector detects a light emission amount and
applies a feedback to an amount of a current to be
supplied to the semiconductor laser light source at the
time of light irradiation. In order to lower a price
of the optical head, it is necessary to use a very
inexpensive optical detector. A commercially
available, inexpensive optical detector is often molded
with a resin (an optical detecting unit is surrounded).
As disclosed in "Chapter 0: Description of
Relationship between Use Wavelength and the Present
Embodiment", 530 nm or less (in particular, 455 nm or
less) is used as a light source wavelength in the
present embodiment. In the case of this wavelength
area, a resin with which the optical detecting unit is
molded (mainly, epoxy resin) causes such a degradation
that occurs when ultraviolet ray has been irradiated if
the wavelength light is irradiated (such as dark yellow
discoloring or occurrence of cracks (fine white
stripes)) and the optical detection characteristics are
impaired. In particular, in the case of the write-once
type information storage medium shown in the present
embodiment, a mold resin degradation is likely to occur
because the storage medium has a pre-groove area 11 as
shown in FIGS. 8A, 8B and 8C. As a focus blurring
detection system of an optical head, in order to remove
adverse effect due to the diffraction light from this
pre-groove area 11, there is most often employed a
"knife-edge technique" of allocating an optical
detector at an image forming position relevant to the
information storage medium (image forming magnification
M is in order of 3 times to 10 times). When the
optical detector is arranged at the image forming
position, high optical density is irradiated onto a
mold resin because light beams are focused on the
optical detector, and resin degradation due to this
light irradiation is likely to occur. This mold resin
characteristic degradation mainly occurs due to a
photon mode (optical action), and however, it is
possible to predict an upper limit value of an
allowable irradiation amount in comparison with a light
emission amount in a thermal mode (thermal excitation).
Assuming the worst case, let us assume an optical
system in which an optical detector is arranged at an
image forming position as an optical head.
From the contents described in "(1) Condition for
thickness Dg of recording layer 3-2" in "3-2-A] Range
requiring application of technique according to the
present embodiment", when an optimal characteristic
change (thermal mode) occurs in the recording layer 3-2
at the time of recording in the present embodiment, it
is considered that a temperature temporarily rises in
the range of 80°C to 150°C in the recording layer 3-2.
In view of a room temperature of about 15°C, a
temperature difference ranges from 65°C to
135°C. Pulse light emissions occur at the time of
recording, and continuous light emissions occur at the
time of reproduction. At the time of reproduction, the
temperature rises in the recording layer 3-2 and a
temperature difference occurs. When an image
forming magnification of a detecting system in the
optical head is M, the optical density of the detected
light focused on the optical detector is obtained as
1/M2 of the optical density of convergence light
irradiated on the recording layer 3-2, and thus, a
temperature rise amount on the optical detector at the
time of reproduction is obtained as ATreaci/M2 which is
a rough estimate. In view of the fact that an upper
limit value of optical density, which can be irradiated
on the optical detector, is converted by the
temperature rise amount, it is considered that the
upper limit value is in order of iyi2 1°C. The
image foaming magnification of the detecting system in
the optical head M is in order of 3 times to 10 times
in general, if the magnification M2 =.
tentatively estimated, it is necessary to set
reproduction power so as to obtain:
ATread/ATwrite = 20 (B-3)
Assuming that a duty ratio of recording pulses at
the time of recording is estimated as 50%, the
following is required:
[Optimal reproduction power]
[Optimal recording power]710 (B-4)
Therefore, in view of formulas (8) to (13)
described later and the above formula (B-4), optimal
reproduction power is assigned as follows:
[Optimal reproduction power]
[Optimal reproduction power]
[Optimal reproduction power]
[Optimal reproduction power]
[Optimal reproduction power]
[Optimal reproduction power]
(Refer to "3-2-E] Basic characteristics relating
to thickness distribution of recording layer in the
present embodiment for definition of parameters".) For
example, when NA = 0.65 and V = 6.6 m/s, the following
is obtained:
[Optimal reproduction power] [Optimal reproduction power] [Optimal reproduction power] In reality, the optical detector is fixed as
compared with the fact the information storage medium
rotates and relatively moves, and thus, in
consideration of this fact, it is necessary to further
set the optimal reproduction power to be in order of
1/3 or less of the value obtained in the above formula.
In the information recording/reproducing apparatus
according to the present embodiment, a value of the
reproduction power is set to 0.4 mW.
3-2-C] Ideal recording film structure in which a
principle of recording shown in the present embodiment
is easily generated
A description will be given with respect to a
method for "setting an environment" (recording film
structure or shape) in which the above principle of
recording is easily generated in the present
embodiment.
As an environment in which an optical
characteristic change inside of the above described
recording layer 3-2 is likely to occur, the present
embodiment is featured in that a technical contrivance
is carried out in recording film structure or shape
such as:
"in an area for forming the recording mark 9, a
critical temperature at which an optical characteristic
change is likely to occur is exceeded, and at a center
part of the recording mark 9, a gasification
(evaporation) temperature is not exceeded, and a
surface of a transparent substrate 2-2 in the vicinity
of the center part of the recording mark 9 does not
exceed a thermal temperature".
The specific contents relating to the above
description will be described with reference to
FIGS. 7A, 7B and 7C. In FIGS. 7A, 7B and 1C, the open
(blank) arrow indicates an optical path of an
irradiation laser light beam 7, and the arrow of the
dashed line indicates a thermal flow. A recording film
structure shown in FIG. 7A indicates an environment in
which an optical characteristic change inside of a
recording layer 3-2 corresponding to the present
embodiment is most likely to occur. That is, in
FIG. 7A, the recording layer 3-2 consisting of an
organic dye recording material has uniform thickness
anywhere in the range shown in formula (3) or formula
(4) (where the thickness is sufficiently large), and
receives irradiation of the laser light beam 7 in a
direction vertical to the recording layer 3-2. As
described in detail in "6-1) light reflection layer
(material and thickness)", a silver alloy is used as a
material for a light reflection layer 4-2 in the
present embodiment. A material including a metal with
high light reflection factor, in general, has high
thermal conductivity and heat radiation characteristics
without being limited to the silver alloy. Therefore,
although a temperature of the recording layer 3-2 is
risen by absorbing the energy of the irradiated laser
light beam 7, a heat is radiated toward the light
reflection layer 4-2 having heat radiation
characteristics. Although a recording film shown in
FIG. 7A is formed anywhere in a uniform shape, a
comparatively uniform temperature rise occurs inside of
the recording layer 3-2, and a temperature difference
at points a, P, and y at the center part is
comparatively small. Therefore, when the recording
mark 9 is formed, when a critical temperature at which
an optical characteristic change at the points a and P
occurs is exceeded, a gasification (evaporation)
temperature is not exceeded at the point a of the
center part; and a surface of a transparent substrate
(not shown) which exists at a position which is the
closest to the point a of the center part does not
exceed a thermal deformation temperature.
In comparison, as shown in FIG. 7B, a step is
provided partly of the recording film 3-2. At the
points 5 and e, the radiation of the laser light beam 7
is subjected in a direction oblique to a direction in
which the recording layer 3-2 is arrayed, and thus, an
irradiation amount of the laser light beam 7 per a unit
area is relatively lowered as compared with the point cc
of the center part. As a result, a temperature rise
amount in the recording layer 3-2 at the points 8 and e
is lowered. At the points 8 and E as well, thermal
radiation toward the light reflection layer 4-2 occurs,
and thus, the arrival temperature at the points 8 and s
is sufficiently lowered as compared with the point a of
the center part. Therefore, a heat flows from the
point P to the point a and a heat flows from the point
a to the point P, and thus, a temperature difference at
the points P and y relevant to the point a of the
center part becomes very small. At the time of
recording, a temperature rise amount at the points P
and y is low, and a critical temperature at which an
optical characteristic change occurs is hardly exceeded
at the points p and a. As countermeasures against it,
in order to produce an optical characteristic change
occurs at the points P and y (in order to produce a
critical temperature or more), it is necessary to
increase an exposure amount (recording power) of the
laser light beam 7. In the recording film structure
shown in FIG. 7B, a temperature difference at the point
a of the center part relevant to the points P and y is
very large. Thus, when a current temperature has risen
at a temperature at which an optical characteristic
change occurs at the points P and y, a gasification
(evaporation) temperature is exceeded at the point a of
the center part or the surface of a transparent
substrate (not shown) in the vicinity of the point a of
the center part hardly exceeds a thermal deformation
temperature.
In addition, even if the surface of the recording
layer 3-2 at the side at which irradiation of the laser
light beam 7 is subjected is vertical to the
irradiation direction of the laser light beam 7
anywhere, in the case where the thickness of the
recording layer 3-2 changes depending on a location,
there is provided a structure in which an optical
characteristic change inside of the recording layer 3-2
according to the present embodiment hardly occurs. For
example, as shown in FIG. 7C, let us consider a case in
which the thickness Dl of a peripheral part is
significantly small with respect to the thickness Dg of
the recording layer 3-2 at the point a of the center
part (for example, formula (2) or formula (4) is not
satisfied). Even at the point a of the center part,
although heat radiation toward the light reflection
layer 4-2 occurs, the thickness Dg of the recording
layer 3-2 is sufficiently large, thus making it
possible to achieve heat accumulation and to achieve a
high temperature. In comparison, at the points 2, and rat which the thickness Dl is significantly small, a
heat is radiated toward the light reflection layer 4-2
without carrying out heat accumulation, and thus, a
temperature rise amount is small. As a result, heat
radiation toward points p, 8, and £, in order and heat
radiation toward points y, e, and r| in order occurs as
well as heat radiation toward the light reflection
layer 4-2, and thus, as in FIG. 7B, a temperature
difference at the point a of the center part relevant
to points P and y becomes very large. When an exposure
amount of the laser light beam 7 (recording power) is
increased in order to produce an optical characteristic
change at the points P and y (in order to produce a
critical temperature or more), the gasification
(evaporation) temperature at the point a of the center
part is exceeded or the surface of the transparent
substrate (not shown) in the vicinity of the point a of
the center part easily exceeds a thermal deformation
temperature.
Based on the contents described above, referring
to FIGS. 8A, 8B and 8C, a description will be given
with respect to: the contents of a technical
contrivance in the present embodiment relating to the
pre-groove shape/dimensions for providing "setting of
environment (structure or shape of a recording film)"
in which a principle of recording according to the
present embodiment is likely to occur; and the contents
of a technical contrivance in the present embodiment
relating to a thickness distribution of the recording
layer. FIG. 8A shows a recording film structure in a
conventional write-once type information storage medium
such as CD-R or DVD-R; and FIGS. 8B and 8C each show a
recording film structure in the present embodiment. In
the invention, as shown in FIGS. 8A, 8B and 8C, a
recording mark 9 is formed in a pre-groove area 11.
3-2-D] Basic characteristics relating to pregroove
shape/dimensions in the present embodiment
As shown in FIG. 8A, there have been many cases in
which a pre-groove area 11 is formed in a "V-groove"
shape in a conventional write-once type information
storage medium such as CD-R or DVD-R. In the case of
this structure, as described in FIG. 7B, the energy
absorption efficiency of the laser light beam 7 is low,
and the temperature distribution non-uniformity in the
recording layer 3-2 becomes very large. The present
embodiment is featured in that, in order to make close
to an ideal state of FIG. 7A, a planar shape orthogonal
to a traveling direction of the incident laser light
beam 7 is provided in the pre-groove area 11 at the
side of at least the "transparent substrate 2-2". As
described with reference to FIG. 7A, it is desirable
that this planar area be as wide as possible.
Therefore, the present embodiment is secondarily
featured in that the planar area is provided in the
pre-groove area 11 and the width Wg of the pre-groove
area 11 is wider than the width Wl of a land area (Wg
Wl). In this description, the width Wg of the pregroove
area and the width Wl of the land area are
defined as their respective widths at a position at
which there crosses a plane having an intermediate
height between a height at a planar position of the
pre-groove area and a height at a position at which the
land area becomes the highest and an oblique surface in
the pre-groove.
A discussion has been made using thermal analysis,
data has been recorded in a write-once type information
storage medium actually produced as a prototype,
substrate deformation observation due to a sectional
SEM (scanning type electronic microscope) image at the
position of the recording mark 9 has been made, and
observation of the presence or absence of a cavity
generated due to gasification (evaporation) in the
recording layer 3-2 has been repeated. As a result, it
is found that advantageous effect is attained by
widening the width Wg of the pre-groove area more
significantly than the width Wl of the land area.
Further, a ratio of the pre-groove area width Wg and
the land area width Wl is Wg:Wl = 6:4, and desirably,
is greater than Wg:Wl = 7:3, whereby it is considered
that a local optical characteristic change in the
recording layer 3-2 is likely to occur while the change
is more stable at the time of recording. As described
above, when a difference between the pre-groove area
width Wg and the land area width Wl is increased, a
flat surface is eliminated from the top of the land
area 12, as shown in FIG. 8C. In the conventional DVDR
disk, a pre-pit (land pre-pit: not shown) is formed
in the land area 12, and a format for recording address
information or the like in advance is realized here.
Therefore, it is conditionally mandatory to form a flat
area in the land area 12. As a result, there has been
a case in which the pre-groove area 11 is formed in the
"V-groove" shape. In addition, in the conventional
CD-R disk, a wobble signal has been recorded in the
pre-groove area 11 by means of frequency modulation.
In a frequency modulation system in the conventional
CD-R disk, slot gaps (a detailed description of each
format is given in detail) are not constant, and phase
adjustment at the time of wobble signal detection (PLL:
synchronization of PLL (Phase Lock Loop)) has been
comparatively difficult. Thus, a wall face of the
pre-groove area 11 is concentrated (made close to the
V-groove) in the vicinity of a center at which the
intensity of a reproducing focusing spot is the highest
and a wobble amplitude amount is increased, whereby the
wobble signal detection precision has been guaranteed.
As shown in FIGS. 8B and 8C, after the flat area in the
pre-groove area 11 in the present embodiment has been
widened, when the oblique surface of the pre-groove
area 11 is shifted to the outside relatively than a
center position of the reproducing focusing spot, a
wobble detection signal is hardly obtained. The
present embodiment is featured in that the width Wg of
the pre-groove area described above is widened and the
H format utilizing PSK (Phase Shift Keying) in which
slot gaps at wobble detection is always fixedly
maintained or the B format utilizing FSK (Frequency
Shift Keying) or STW (Saw Tooth Wobble) are combined,
whereby stable recording characteristics are guaranteed
(suitable to high speed recording or layering) at low
recording power and stable wobble signal detection
characteristics are guaranteed. In particular, in the
H format, in addition to the above combination, "a
ratio of a wobble modulation is lowered more
significantly than that of a non-modulation area",
thereby facilitating synchronization at the time of
wobble signal detection more significantly, and
further, stabilizing wobble signal detection
characteristics more significantly.
3-2-E] Basic characteristics relating to thickness
distribution of recording layer 3-2 in the present
embodiment
In the present description, as shown in FIGS. 8B
and 8C, the thickness in a portion at which the
recording layer 3-2 in the land area 12 is the thickest
is defined as recording layer thickness Dl in the land
area 12; and a portion at which the recording layer 3-2
in the pre-groove area 11 is the thickest is defined as
recording layer thickness Dg in the pre-groove area.
As has been described with reference to FIG. 1C, the
recording layer thickness Dl in the land area is
relatively increased, whereby a local optical
characteristic change in the recording layer is stably
likely to occur at the time of recording.
In the same manner as that described above, a
discussion has been made using thermal analysis, data
has been recorded in a write-once type information
storage medium actually produced as a prototype,
substrate deformation observation and observation of
the presence or absence of a cavity generated due to
gasification (evaporation) in the recording layer 3-2
by a sectional SEM (scanning type electronic
microscope) image at the position of the recording mark
9 have been made. As a result, it has been found
necessary to set a ratio between the recording layer
thickness Dg in the pre-groove area and the recording
layer thickness Dl in the land area to be equal to or
smaller than Dg:Dl = 4:1. Further, Dg:Dl = 3:1 is set,
and desirably, Dg:Dl = 2:1 is set, thereby making it
possible to guarantee stability of a principle of
recording in the present embodiment.
3-3) Recording characteristics common to organic
dye recording film in the present embodiment
As one of "3-2-B] basic characteristics common to
an organic dye recording material in the present
embodiment", the present embodiment is featured by
recording power control, as described in item [y] .
The formation of the recording mark 9 due to a
local optical characteristic change in the recording
layer 3-2 occurs at a temperature, which is much lower
than a plastic deformation temperature of the
conventional transparent substrate 2-2, at a thermal
decomposition temperature in the recording layer 3-2,
or a gasification (evaporation) temperature. Thus, an
upper limit value of recording power is restricted so
as not ensure that the transparent substrate 2-2
locally exceeds a plastic deformation temperature at
the time of recording or a thermal decomposition
temperature or a gasification (evaporation) temperature
is locally exceeded in the recording layer 3-2.
In parallel to discussion using thermal analysis,
by using an apparatus described later in "4-1)
Description of structure and characteristics of
reproducing apparatus or recording/reproducing
apparatus in the present embodiment" and by using a
recording condition described later in "4-3)
Description of recording condition in the present
embodiment", there has been made a demonstration of a
value of optimal power in the case where recording has
been carried out in a principle of recording shown in
the present embodiment. A numerical aperture (NA)
value of an objective lens in the recording/reproducing
apparatus used in a demonstration test has been 0.65,
and a line speed at the time of recording has been
6.61 m/s. As a value of recording power (Peak Power)
defined later in "4-3) Description of recording
condition in the present embodiment", it has been found
that:
• Gasification (evaporation) occurs with most of
an organic dye recording material at 30 mW, and a
cavity occurs in a recording mark;
A temperature of the transparent substrate 2-2
at a position in the vicinity of the recording layer 3-
2 significantly exceeds a glass transition temperature;
• A temperature of the transparent substrate 2-2
at a position in the vicinity of the recording layer
3-2 reaches a plastic deformation temperature (glass
transition temperature) at 20 mW;
• 15 mW or less is desirable in consideration of a
margin such as surface pre-warping or recording power
change of an information storage medium.
The "recording power" described above denotes a
sum of exposure amount irradiated to the recording
layer 3-2. The optical energy density at a center part
of a focusing spot and at a portion at which the
optical intensity density is the highest is obtained as
parameters targeted for discussion in the present
embodiment. The focusing spot size is inversely
proportional to the NA value, and thus, the optical
energy density at the center part of the focusing spot
increases in proportion to a square of the NA value.
Therefore, the current value can be converted to a
value of optimal recording power in the B format
described later or another format (another NA value)
shown in FIG. 1 (D3) by using a relational formula
below:
[Recording power applicable to different NA
values]
= [Recording power when NA = 0.65] x 0.652/NA2
(5)
Further, optimal recording power changes depending
on a line speed V in phase change type recording
material. In general, it is said that optimal
recording power changes in proportion to a 1/2 square
of a line speed V in phase change type recording
material, and changes in proportion to a line speed V
in organic dye recording material. Therefore, a
conversion formula of optimal recording power
considering a line speed V, obtained by extending
formula (5), is obtained as follows:
[General recording power]
= [Recording power when NA = 0.65; 6.6 m/s] x
(0.65/NA)2 x (V/6.6) (6)
or
[General recording power]
= [Recording power when NA = 0.65; 6.6 m/s] x
(0.65/NA)2 x (V/6.6)l/2 (7)
When the above discussion result is summarized, as
recording power for guaranteeing a principle of
recording shown in the present embodiment, it is
desirable to set an upper limit value such as:
[Optimal recording power]
[Optimal recording power]
[Optimal recording power]
[Optimal recording power]
[Optimal recording power]
[Optimal recording power]
From among the above formulas, a condition for
formula (8) or formula (9) is obtained as a mandatory
condition; a target condition for formula (10) or
formula (11) is obtained; and a condition for formula
(12) or formula (13) is obtained as a desirable
condition.
3-4) Description of characteristics relating to
"H-L" recording film in the present embodiment
A recording film having characteristics that a
light reflection amount in a recording mark 9 is lower
than that in an unrecorded area is referred to as an
"H-L" recording film. In contrast, a recording film in
which the above light reflection amount is high is
referred to as an "L-H" recording film. Among them,
with respect to the "H-L" recording film, the present
embodiment is featured in that:
1) an upper limit value is provided at a ratio of
absorbance at a reproduction wavelength relevant to
absorbance at a Viax write position of light absorption
spectra; and
2) a light absorption spectra profile is changed
to form a recording mark.
A detailed description relating to the above
contents will be given with reference to FIGS. 9 and
10. In the "H-L" recording film in the present
embodiment, as shown in FIG. 9, a wavelength of A.max
write is shorter than a use wavelength utilized for
recording/reproduction (in the vicinity of 405 nm). As
is evident from FIG. 10, in the vicinity of a
wavelength of A,max write' change of absorbance is
small between an unrecorded portion and a recorded
portion. If a change of absorbance is small between
the unrecorded portion and the recorded portion, a
large reproduction signal amplitude cannot be obtained.
Even if a wavelength change of a recording or
reproducing laser light source occurs, in view of the
fact that recording or reproduction can be stably
carried out, in the present embodiment, as shown in
FIG. 9, a design of the recording film 3-2 is made so
that a wavelength of A,max Write arrives at the outside
ranging from 355 nm to 455 nm, i.e., arrives at the
shorter wavelength side than 355 nm.
The relative absorbance at 355 nm, 455 run, and
405 nm described in "Chapter 0: Description of
Relationship between Use Wavelength and the Present
Embodiment" when the absorbance at a position of A,max
write defined in "2-1) Difference in principle of
recording/recording film structure and difference in
basic concept relating to reproduction signal
generation", is defined as Ah355, Ah455, and Ah4Q5.
In the case where of Ah4Q5 = 0.0, the light
reflection factor from a recording film in an
unrecorded state coincides with that at 405 nm in the
light reflection layer 4-2. A light reflection factor
of the light reflection layer 4-2 will be described
later in detail in the section "6-1) Light reflection
layer". Hereinafter, a description will be given with
respect to the fact that the light reflection factor of
the light reflection layer 4-2 is defined as 100% for
the sake of simplification.
In the write-once type information storage medium
using an "H-L" recording film in the present
embodiment, a reproduction circuit is used in common to
a case of using a read-only type information storage
medium (HD DVD-ROM disk) in the case of a one-sided
single layer film. Therefore, in this case, an optical
reflection factor is defined as 45% to 85% in
accordance with a light reflection factor of the
reflection only information storage medium (HD DVD-ROM
disk) of a one-sided single layer film. Therefore, it
is necessary to set the light reflection factor at an
unrecorded position to 40% or more. Because 1 - 0.4 =
0.6, it is possible to intuitively understand whether
or not the absorbance Ah4Q5 at 405 nm may be set:
Ah405 In the case where formula (14) above is met, it is
possible to easily understand that the light reflection
factor can be set to 40% or more. Thus, in the present
embodiment, an organic dye recording material, which
meets formula (14) in an unrecorded location, is
selected. The above formula (14) assumes that, in
FIG. 9, the light reflection factor is obtained as 0%
when the light reflection layer 4-2 is reflected over
the recording layer 3-2 with a light beam having a
wavelength of A,max write- However, in reality, at this
time, the light reflection factor is not obtained as
0%, and has a certain degree of light reflection
factor. Thus, strictly, there is a need for correction
relevant to formula (14). In FIG. 9, if the light
reflection factor is defined as RXmax write when the
light reflection layer 4-2 has been reflected over the
recording layer 3-2 with a light beam having a
wavelength of A,max Write' a strict conditional formula
in which the light reflection factor at an unrecorded
position is set to 40% or more is obtained as follows:
I - Ah405 x (1 - R^max write) ^ 0.4 (15)
In the "H-L" recording layer, in many cases,
write) - °-25, and thus, formula (15) is established as
follows:
Ah4o5 0.8 (16)
In the "H-L" recording film according to the
present embodiment, it is conditionally mandatory to
meet formula (16). Characteristics of the above
formula (14) has been provided, and further, a detailed
optical film design has been made under a condition
that the film thickness of the recording layer 3-2
meets the condition for formula (3) or formula (4), in
consideration of a variety of margins such as a film
thickness change or a wavelength change of reproduction
light. As a result, it has been found desirable that:
Ah405 0.3 (17)
Assuming that formula (14) is established, when:
the recording/reproducing characteristics are more
stable. This is because, in the case where formula
(14) meets any of at least formulas (18) and (19) when
formula (14) is established, the value of Ah becomes
0.6 or less in the range of 355 nm to 405 nm or in the
range of 405 nm to 455 nm (occasionally in the range of
355 nm to 455 nm), and thus, even if a fluctuation
occurs at a light emission wavelength of a recording
laser light source (or a reproducing laser light
source), a value of absorbance does not change
drastically.
As a specific principle of recording of the "H-L"
recording film in the present embodiment, there is
utilized a phenomenon of "array change between
molecules" or "molecular structure change in molecule"
in a recording mechanism listed in item [a] in "3-2-B]
Basic featured common to organic dye recording material
in the present embodiment" which has been described as
a specific principle of recording of the "H-L"
recording film in the present embodiment. As a result,
as described in the above item (2), a light absorption
spectrum profile is changed. The light absorption
spectrum profile in a recording mark in the present
embodiment is indicated by the solid line shown in
FIG. 10, and the light absorption spectrum profile in
an unrecorded location is superimposed by the dashed
line, thereby making it possible to compare these
profiles with each other. In the present embodiment,
the light absorption spectrum profile in the recording
mark changes comparatively broadly, and there is a
possibility that a molecular structure change in
molecules occurs and partial precipitation (coal tar)
of carbon atoms occurs. The present embodiment is
featured in that a value of a wavelength ^-Imax a^ which
the absorbance in the recording mark becomes maximal is
made closer to a reproduction wavelength of 405 nm than
a value of a wavelength write at an unrecorded
position, thereby generating a reproduction signal in
the "H-L" recording film. In this manner, the
absorbance at the wavelength A,lmax at which the
absorbance is the highest becomes smaller than "1", and
a value of the absorbance A14Q5 at a reproduction
wavelength of 405 nm becomes greater than a value of
Ah4Q5- As a result, a total light reflection factor in
a recording mark is lowered.
In the H format in the present embodiment, as a
modulation system, there is employed ETM (Eight to
Twelve: 8-bit data code is converted to 12-channel bit)
and RLL (1, 10) (Among a code train after modulated, a
minimum inversion length relevant to a 12-channel bit
length T is 2T, and a maximum inversion length is 11T).
Where performance evaluation of a reproduction circuit
described later in "4-2) Description of reproducing
circuit in the present embodiment) is carried out, in
order to stably carry out reproduction by the
reproducing circuit, it has been found necessary to
meet that a ratio of [differential value 111 = IHH ~
IHL between the I11H and reproduction signal amount
IHL from a recording mark having a sufficiently long
length (11T)] is:
I11/I11H °-4 (2°) or preferably,
I11/I11H > 0.2 (21)
In the present embodiment, a PRML method is
utilized at the time of signal reproduction recorded at
high density, and a signal processor circuit and a
state transition chart shown in FIGS. 15 to 17 is used
(A detailed description is given later). In order to
precisely carry out detection in accordance with a PRML
technique, the linearity of a reproduction signal is
requested. The characteristic of the signal processor
circuit shown in FIGS. 15 and 16 has been analyzed
based on the state transition chart shown in FIG. 17,
in order to ensure the linearity of the above
reproduction signal. As a result, it has been found
necessary to meet that a ratio relevant to the above
of a value when a recording mark having a length of
3T and a reproduction signal amplitude from a
repetition signal of an unrecorded space is defined as
13 meets:
l3/Ill 0.35 (22); or desirably,
I3/In 0.2 (23)
In view of a condition for the above formula (16),
the present embodiment is technically featured in that
a value of AlQS been set so as to meet formulas
(20) and (21). Referring to formula (16), the
following is obtained:
1 - 0.3 = 0.7 (24)
In view of formula (24), from a correlation with
formula (20), the following condition is derived:
(A1405 ~ 0.3)/0.7 0.4, that is,
A1405 2. 0.58 (25)
Formula (25) is a formula derived from a very
coarse result of discussion, and is merely shown as a
basic concept. Because the Ah4Q5 setting range is
specified in accordance with formula (16), in the
present embodiment, at least a condition for A14Q5 is
mandatory as:
A1405 > 0.3 (26)
As a method for selecting an organic dye material
suitable to a specific "H-L" recording layer, there is
selected an organic dye material for which, in the
present embodiment, based on an optical film design, a
refractive factor range in an unrecorded state is
1.3 to 2.0; the absorption coefficient range is
0.1 to 0.2, desirably n32 = 1.7 to 1.9; the absorption
coefficient range is k-2 = 0.15 to 0.17, and a series
of conditions described above are met.
In the "H-L" recording film shown in FIG. 9 or 10,
in light absorption spectra in an unrecorded area,
although a wavelength of write is shorter than a
wavelength of reproduction light or
recording/reproducing light (for example, 405 nm), the
wavelength of write longer than a
wavelength of reproduction light or
recording/reproducing light (for example, 405 nm),
without being limited thereto.
In odder to meet the above formula (22) or formula
(23), the thickness Dg of the recording layer 3-2 is
influenced. For example, if the thickness Dg of the
recording layer 3-2 significantly exceeds an allowable
value, optical characteristics of only a part coming
into contact with the transparent substrate 2-2 in the
recording layer 3-2 are changed as a state that follows
forming of the recording mark 9, whereby the optical
characteristics of a portion coming into contact with
the light reflection layer 4-2 adjacent to its location
are obtained as a value equal to that in the unrecorded
area. As a result, a reproduction light amount change
is lowered, and a value of 13 in formula (22) or
formula (23) is reduced, and a condition for formula
(22) or formula (23) cannot be met. Therefore, in
order to meet formula (22), as shown in FIGS. 8B and
8C, it is necessary to make a change to the optical
characteristics of a portion which comes into contact
with the light reflection layer 4-2 in the recording
mark 9. Further, if the thickness Dg of the recording
layer 3-2 significantly exceeds an allowable value, a
temperature gradient occurs in the thickness direction
in the recording layer 3-2 when the recording mark is
formed. Then, before reaching the optical
characteristic change temperature at a portion coming
into contact with the light reflection layer 4-2 in the
recording layer 3-2, a gasification (evaporation)
temperature of a portion coming into contact with the
transparent substrate 2-2 is exceeded or a thermal
deformation temperature is exceeded in the transparent
substrate 2-2. For the above reason, in the present
embodiment, in order to meet formula (22), the
thickness Dg of the recording layer 3-2 is set to "3T"
or less based on the discussion of thermal analysis;
and a condition meeting formula (23) is such that the
thickness Dg of the recording layer 3-2 is set to
"3 x 3T" or less. Basically, in the case where the
thickness Dg of the recording layer 3-2 is equal to or
smaller than "3T", although formula (22) can be met,
the thickness may be set to "T" or less in
consideration of effect of a tilt due to a facial
motion or warping of the write-once type information
storage medium or a margin relevant to a focal
blurring. In consideration of a result obtained by
formulas (1) and (2) described previously, the
thickness Dg of the recording layer 3-2 in the present
embodiment is set in the range assigned in a required
minimum condition that:
9T > Dg > X/8n32 (27)
and in a desired condition that:
3T > Dg > X/4n32 (28)
Without being limited thereto, the severest
condition can be defined as:
T > Dg > L/4n32 (29)
As described later, a value of the channel bit
length T is 102 nm in the H format, and is 69 nm to
80 nm in the B format. Thus, a value of 3T is 306 nm
in the H format and is 207 nm to 240 nm in the B
format. A value of 9T is 918 nm in the H format and is
621 nm to 720 nm in the B format. Here, although an
"H-L" recording film has been described, the conditions
for formulas (27) to (29) can be applied to an "L-H"
recording film without being limited thereto.
Chapter 4 Description of Reproducing Apparatus or
Recording/Reproducing Apparatus and Recording
Condition/Reproducing Circuit
4-1) Description of structure and characteristics
of reproducing apparatus or recording/reproducing
apparatus in the present embodiment
FIG. 11 shows an illustration of a structure in an
embodiment of an information recording/reproducing
apparatus. In FIG. 11, an upper side of a control unit
143 mainly indicates an information recording control
system for an information storage medium. In the
embodiment of the information reproducing apparatus, a
structure excluding the information recording control
system in FIG. 11 corresponds to the above structure.
In FIG. 11, the arrow drawn by the thick solid line
indicates a flow of main information which designates a
reproduction signal or a recording signal; the arrow of
the thin solid line denotes a flow of information; the
arrow of the one-dotted chain line denotes a reference
clock line; and the arrow of the thin dashed line
denotes a command indicating direction.
An optical head (not shown) is arranged in an
information recording/reproducing unit 141 shown in
FIG. 11. In the present embodiment, although a
wavelength of a light source (semiconductor laser) used
in the optical head is 405 nm, the present embodiment
is not limited thereto, and there can be used a light
source having a use wavelength equal to or shorter than
620 nm or 530 nm or a light source ranging from 355 nm
to 455 nm, as described previously. In addition, two
objective lenses used to focus the light beam having
the above wavelength onto the information storage
medium may be incorporated in the optical head. In the
case where a recording/reproducing operation is carried
out with respect to an information storage medium in
the H format, an objective lens having a NA value of
0.65 is used. A structure is provided such that, in
the case where a recording/reproducing operation is
carried out with respect to an information storage
medium in the B format, an objective lens having NA =
0.85 is used. As an intensity distribution of incident
light immediately before the light is incident to an
objective lens, the relative intensity at the periphery
of the objective lens (at the boundary position of an
aperture) when the center intensity is set to "1" is
referred to as "RIM Intensity". A value of the RIM
intensity in the H format is set in the range of 55% to
70%. At this time, a wave surface aberration amount in
the optical head is optically designed so as to be
0.33A, (0.33X or less) with respect to a use
wavelength A,.
In the present embodiment, a partial response
maximum likelihood (PRML) is used for information
reproduction to achieve high density of an information
storage medium (FIG. 1, point [A]). As a result of a
variety of tests, when PR(1, 2, 2, 2, 1) is used as a
PR class to be used, line density can be increased and
the reliability of a reproduction signal can be
improved (i.e., demodulation reliability can be
improved) when a servo correction error such as a focal
blurring or a track shift has occurred. Thus, in the
present embodiment, PR(1, 2, 2, 2, 1) is employed
(FIG. 1, point [Al]). In the present embodiment, a
channel bit pattern after modulated is recorded in an
information storage medium in accordance with a (d, k;
m, n) modulation rule (In the above described method,
this denotes RLL(d, k) of m/n modulation).
Specifically, ETM (Eight to Twelve Modulation) for
converting 8-bit data to a 12-channel bit (m = 8, n =
12) is employed as a modulation system, and a condition
of RLL (1, 10) in which a minimum value having
continuous "0"s is defined as d = 1, and a maximum
value is defined as k = 10 as a run length limited RLL
restriction for apply limitation to a length that
follows "0" in the channel bit pattern after modulated
must be met. In the present embodiment, in order to
achieve high density of an information storage medium,
a channel bit gap is reduced to the minimum. As a
result, for example, after a pattern
"101010101010101010101010" which is a repetition of a
pattern of d = 1 has been recorded in the information
storage medium, in the case where the data is
reproduced in an information recording/reproducing unit
141, the data is close to a shutdown frequency having
MTF characteristics of a reproducing optical system,
and thus, a signal amplitude of a reproduced raw signal
is formed in a shape almost hidden by noise.
Therefore, a partial response maximum likelihood (PRML)
technique is used as a method for thus reproducing a
recording mark or a pit, which has been dense up to the
vicinity of a limit of the MTF characteristics
(shutdown frequency). That is, a signal reproduced
from the information recording/reproducing unit 141
receives reproducing waveform correction by a PR
equalizer circuit 130. A signal having passed through
the PR equalizer circuit 130 is sampled by converting a
signal after passing through the PR equalizer circuit
130 to a digital amount in accordance with a timing of
a reference clock 198 sent from a reference clock
generating circuit 160; the sampled signal is converted
to a digital data by an AD converter 169; and a Viterbi
decoding process is carried out in a Viterbi decoder
156. The data after Viterbi-decoded is processed as
data, which is completely similar to binary data at a
conventional slice level. In the case where the PRML
technique has been employed, if a sampling timing
obtained by the AD converter 169 is shifted, an error
rate of the data after Viterbi decoded increases.
Therefore, in order to enhance precision of the
sampling timing, the information reproducing apparatus
or information recording/reproducing apparatus
according to the present embodiment has another
sampling timing sampling circuit in particular
(combination of Schmidt trigger binarizing circuit 155
and PLL circuit 174). This Schmidt trigger circuit 155
has a specific value (forward direction voltage value
of diode in actuality) at a slice reference level for
binarizing, and is featured in that binarizing is
provide only when the specific width has been exceeded.
Therefore, for example, as described above, in the case
where a pattern of "101010101010101010101010" has been
input, a signal amplitude is very small, and thus,
switching of binarizing does not occur. In the case
where "1001001001001001001001" or the like, for
example, being a pattern of a rarer fraction than the
above, has been input, an amplitude of a reproducing
raw signal increases, and thus, the polarity switching
of a binary signal occurs in accordance with a timing
of "1" by a Schmidt trigger binarizing circuit 155. In
the present embodiment, an NRZI (Non Return to Zero
Invert) technique is employed, and a position of "1" of
the above pattern coincides with an edge section
(boundary section) of a recording mark or a pit.
A PLL circuit 174 detects a shift in frequency and
phase between a binary signal which is an output of
this Schmidt trigger binarizing circuit 155 and a
signal of a reference clock 198 sent from a reference
clock generating circuit 160 to change the frequency
and phase of the output clock of the PLL circuit 174.
A reference clock generating circuit 160 applies a
feedback to (a frequency and a phase) of a reference
clock 198 so as to lower an error rate after Viterbi
decoded, by using an output signal of this PLL circuit
174 and decoding characteristic information on a
Viterbi decoder 156 and a convergence length
(information on (distance to convergence)) in a path
metric memory in the Viterbi decoder 156, although is
not specifically shown). The reference clock 198
generated by this reference clock generating circuit
160 is utilized as a reference timing at the time of
reproduction signal processing.
A sync code position sampling unit 145 serves to
detect the presence and position of a sync code, which
coexists in an output data train of the Viterbi decoder
156 and to sample a start position of the above output
data. While this start position is defined as a
reference, a demodulator circuit 152 carries out a
demodulating process with respect to data temporarily
stored in a shift resistor circuit 170. In the present
embodiment, the above temporarily stored data is
returned to its original bit pattern with reference to
a conversion table recorded in a demodulating
conversion table recording unit 154 on 12-channel bit
by bit basis. Then, an error correcting process is
performed by an ECC decoding circuit 162, and
descrambling is carried out by a descrambling circuit
159. Address information is recorded in advance by
wobble modulation in a recording type (rewritable type
or write-once type) information storage medium
according to the present embodiment. A wobble signal
detecting unit 135 reproduces this address information
(i.e., judges the contents of a wobble signal), and
supplies information required to provide an access to a
desired location to the control unit 143.
A description will be given with respect to an
information recording control system provided at the
upper side than the control unit 143. After data ID
information has been generated from a data ID
generating unit 165 in accordance with a recording
position on an information storage medium, when copy
control information is generated by a CPR_MAI data
generating unit 167, a variety of information on data
ID, IED, CPRJMAI, and EDC is added to information to be
recorded by a data ID, IED, CPR_MAI, and EDC adding
unit 168. After the added information has been
descrambled by the descrambling circuit 157, an ECC
block is formed by an ECC encoding circuit 161, and the
ECC block is converted to a channel bit pattern by a
modulating circuit 151. A sync code is added by a sync
code generating/adding unit 146, and data is recorded
in an information storage medium in the information
recording/reproducing unit 141. At the time of
modulation, DSV values after modulated are sequentially
calculated by a DSV (Digital Sum Value) calculating
unit 148, and the serially calculated values are fed
back to code conversion after modulated.
FIG. 12 shows a detailed structure of peripheral
portions including the sync code position detector unit
145 shown in FIG. 11. A sync code is composed of a
sync position detecting code section and a variable
code section having a fixed pattern. From the channel
bit pattern output from a Viterbi decoder, a sync
position detecting code detector unit 182 detects a
position of a sync position detecting code section
having the above fixed pattern. Variable code transfer
units 183 and 184 sample data on a variable code which
exists before and after the detected position, and
judge in which sync frame in a sector the sync code is
positioned, the sync code being detected by an
identifying unit 185 for detecting a sync position
having the above fixed pattern. User information
recorded on an information storage medium is
sequentially transferred in order of a shift register
circuit 170, a demodulation processing unit 188 in a
demodulator circuit 152, and an ECC decoding
circuit 162.
In the present embodiment, in the H format, the
high density of the information storage medium is
achieved (in particular, line density is improved) by
using the PRML system for reproduction in a data area,
a data lead-in area, and a data lead-out area. In
addition, compatibility with a current DVD is ensured
and reproduction stability is ensured by using a slice
level detecting system for reproducing in a system
lead-in area and a system lead-out area. (A detailed
description will be given later in "Chapter 7:
Description of H Format".)
4-2) Description of reproducing circuit in the
present embodiment
FIG. 13 shows an embodiment of a signal
reproducing circuit using a slice level detecting
system used at the time of reproduction in a system
lead-in area and a system lead-out area. A quadrature
optical detector 302 in FIG. 13 is fixed into the
optical head, which exists in the information
recording/reproducing unit 141 in FIG. 11.
Hereinafter, a signal having taken a sum of detection
signals obtained from optical detecting cells la, Ib,
Ic, and Id of the quadrature optical detector 302 is
referred to as a "lead channel 1 signal". From a
preamplifier 304 to a slicer 310 in FIG. 13 corresponds
to a detailed structure in the slice level detecting
circuit 132 in FIG. 11. A reproduction signal obtained
from an information storage medium is subjected to a
waveform equalizing process by a pre-equalizer 308
after the signal has passed through a high path filter
306 which shuts out a frequency component lower than a
reproduction signal frequency bandwidth. According to
testing, it has found that this pre-equalizer 308
minimizes a circuit scale by using a 7-tap equalizer
and can detect a reproduction signal precisely. Thus,
in the present embodiment, the 7-tap equalizer is used.
A VFO circuit/PLL 312 in FIG. 13 corresponds to the PLL
circuit 174 in FIG. 11; and a demodulating/ECC decoding
circuit 314 in FIG. 13 corresponding to the decoding
circuit 152 and the ECC decoding circuit 162 in
FIG. 11.
FIG. 14 shows a detailed structure in a circuit of
the slicer 310 in FIG. 13. A binary signal after
sliced is generated by using a comparator 316. In
response to an inverting signal of binary data after
binarized is set at a slice level at the time of
binarizing. In the present embodiment, a cutoff
frequency of this low path filter is set to 5 KHz.
When this cutoff frequency is high, a slice level
change is fast, and the low path filter is affected by
noise. In contrast, if a cutoff frequency is low, a
slice level response is slow, and thus, the filter is
affected by dust or scratch on the information storage
medium. The cutoff frequency is set to 5 KHz in
consideration of a relationship between RLL(1, 10) and
a reference frequency of a channel bit described
previously.
FIG. 15 shows a signal processor circuit using a
PRML detecting technique used for signal reproduction
in a data area, a data lead-in area, and a data leadout
area. A quadrature optical detector 302 in FIG. 15
is fixed into the optical head, which exists in the
information recording/reproducing unit 141 in FIG. 11.
Hereinafter, a signal having taken a sum of detection
signals obtained from the optical detecting cells la,
lb, Ic, and Id of the quadrature optical detector 302
is referred to as a "lead channel 1 signal". A
derailed structure in the PR equalizer circuit 130 in
FIG. 11 is composed of circuits from a preamplifier 304
to a tap controller 332, an equalizer 330, and an
offset canceller 336 in FIG. 15. A PLL circuit 334 in
FIG. 15 is a part in the PR equalizer circuit 130, and
denotes an element other than the Schmidt trigger
binarizing circuit 155. A primary cutoff frequency of
a high path filter circuit 306 in FIG. 15 is set at
1 KHz. A pre-equalizer circuit 308 uses a 7-tap
equalizer in the same manner as that in FIG. 13
(because the use of the 7-tap equalizer minimizes a
circuit scale and can detect a reproduction signal
precisely). A sample clock frequency of an A/D
converter circuit 324 is set to 72 MHz, and a digital
output is produced as an eight-bit output. In the PRML
detecting technique, if a reproduction signal is
affected by a level change (DC offset) of its entire
signal, an error is likely to occur at the time of
Viterbi demodulation. In order to eliminate such an
effect, there is provided a structure of correcting an
offset by the offset canceller 336 using a signal
obtained from an equalizer output. In the embodiment
shown in FIG. 15, an adaptive equalizing process is
carried out in the PR equalizer circuit 130. Thus, a
tap controller for automatically correcting tap
coefficients in the equalizer 330 is utilized by
utilizing an output signal of the Viterbi decoder 156.
FIG. 16 shows a structure in the Viterbi decoder
156 shown in FIG. 11 or 15. A branch metric relevant
to all branches, which can be predicted in response to
an input signal, is calculated by a branch metric
calculating unit 340, and the calculated value is sent
to an ACS 342. The ACS 342 is an acronym of Add
Compare Select, which calculates a path metric obtained
by adding branch metrics in response to each of the
passes which can be predicted in the ACS 342 and
transfers the calculation result to a path metric
memory 350. At this time, in the ACS 342, a
calculating process is carried out with reference to
the information contained in the path metric memory
350. A path memory 346 temporarily stores a value of
the path metric corresponding to each path (transition)
state and such each path, which can be predicted in the
memory 346, the value being calculated by the ACS 342.
An output switch unit 348 compares a path metric
corresponding to each path, and selects a path when a
path metric value becomes minimal.
FIG. 17 shows a state change in PR(1, 2, 2, 2, 1)
class in the present embodiment. A change of a state
which can be obtained in the PR(1, 2, 2, 2, 1) class
can be made as only a change shown in FIG. 17, and a
path which can exist (which can be predicted) at the
time of decoding is identified in the Viterbi decoder
156 based on a transition chart in FIG. 17.
4-3) Description of recording condition in the
present embodiment
"A description of optimal recording power (peak
power) in the present embodiment has been given in
"3-3) Recording characteristics common to organic dye
recording film in the present embodiment". Referring
to FIG. 18, a description will be given with respect to
a recording waveform (exposure condition at the time of
recording) used when the optimal recording power is
checked.
The exposure levels at the time of recording have
four levels of recording power (peak power), bias power
1, bias power 2, and bias power 3. When a long (4T or
more) recording mark 9 is formed, modulation is carried
out in the form of multi-pulses between recording power
(peak power) and bias power 3. In the present
embodiment, in any of the H format and B format
systems, a minimum mark length relevant to a channel
bit length T is obtained as 2T. In the case where this
minimum mark of 2T is recorded, one write pulse of
recording power (peak power) after bias power 1 is used
as shown in FIG. 18, and bias power 2 is temporarily
obtained immediately after the write pulse. In the
case where a 3T recording mark 9 is recorded, bias
power 2 is temporarily used after exposing two write
pulses, a first pulse and a last pulse of recording
power (peak power) level that follows bias power 1. In
the case where a recording mark 9 having a length of 4T
or more is recorded, bias power 2 is used after multipulse
and write pulse exposure.
The vertical dashed line in FIG. 18 shows a
channel clock cycle. In the case where a 2T minimum
mark is recorded, the laser power is risen at a
position delayed by TSFP from a clock edge, and fallen
at a position, which is backward by TELP from an edge
of a succeeding clock. A cycle during which the laser
power is set at bias power 2 is defined as TLO Values
of TSFP, TELp, and TLC are recorded in physical format
information PFI contained in a control data zone CDZ as
described later in the case of the H format. In the
case where a 3T or more long recording mark is formed,
the laser power is risen at a position delayed by TSFP
from a clock edge, and lastly, ended with a last pulse.
Immediately after the last pulse, the laser power is
kept at the bias power 2 during a period of TLQ. Shift
times from a clock edge to a rise/fall timing of the
last pulse are defined as TSLP^ TELP- In addition, a
shift time from a clock edge to a fall timing of the
last pulse is defined as TEEp, and further, an interval
of a single pulse of a multi-pulse is defined as T^p.
Each of intervals TELP - TSFP, TMP, TELP - TSLP,
and TLC is defined as a half-value wide relevant to a
maximum value, as shown in FIG. 19. In addition, in
the present embodiment, the above parameter setting
range is defined as follows:
0.25T O.OOT LOOT - 0.10T O.OOT 0.1ST Further, in the present embodiment, the values of
the above described parameters can be changed as shown
in FIGS. 20A, 20B and 20C according to a recording mark
length (Mark Length) and the immediately
preceding/immediately succeeding space length
(Leading/Trailing space length). FIGS. 21A, 21B and
21C each shows parameter values when optimal recording
power of the write-once type information storage medium
recorded in a principle of recording shown in the
present embodiment has been checked, as described in
the section "3-3) Recording characteristics common to
organic dye recording film in the present embodiment".
At this time, the values of bias power 1, bias power 2,
and bias power 3 are 2.6 mW, 1.7 mW, and 1.7 mW, and
reproduction power is 0.4 mW.
Chapter 5: Specific Description of Organic Dye
Recording Film in the Present Embodiment
5-1) Description of characteristics relating to
"L-H" recording film in the present embodiment
A description will be given with respect to an "LH"
recording film having characteristics in which a
light reflection amount is lowered in a recording mark
as compared with that in an unrecorded area. From
among principles of recording described in "3-2-B]
Basic characteristics common to organic dye recording
material in the present embodiment", a principle of
recording in the case of using this recording film
mainly utilizes any of:
- Chromogenic characteristic change;
- Change of electron structure (electron orbit)
relevant to elements which contribute to chromogenic
phenomenon [discoloring action or the like]; and
- Array change between molecules, and changes
characteristics of light absorption spectra. The "L-H"
recording film is featured in that the reflection
amount range in an unrecorded location and a recorded
location has been specified in view of characteristics
of a read-only type information storage medium having a
one-sided two-layered structure. FIG. 22 shows a light
reflection factor range in an unrecorded area (nonrecording
portion) of the "H-L" recording film and the
"L-H" recording film according to the present
embodiment. In the present embodiment, the lower limit
value 8 of the reflection factor at the non-recording
portion of the "H-L" recording film is specified so as
to be higher than an upper limit value y at the nonrecording
portion of the "L-H" recording film. When
the above information storage medium has been mounted
on an information recording/reproducing apparatus or an
information reproducing apparatus, a light reflection
factor of the non-recording portion is measured by the
slice level detector unit 132 or the PR equalizer
circuit 130 shown in FIG. 11, thereby making it
possible to judge whether the film is the "H-L"
recording film or "L-H" recording film, and thus,
making it very easy to judge type of recording film.
Measurement has been carried out while producing the
"H-L" recording film and the "L-H" recording film under
a changed manufacturing condition, when a light
reflection factor a between the lower limit value 8 at
the non-recording portion of the "H-L" recording film
and the upper limit value y at the non-recording
portion of the "L-H" recording film is set in the range
of 32% to 40%. As a result, it has been found that
high manufacturing performance of the recording film is
obtained and medium cost reduction is facilitated.
After an optical reflection factor range 801 of a nonrecording
portion ("L" portion) of the "L-H" recording
film is made coincident with a light reflection factor
range 803 of a one-sided double recording layer in the
read-only type information storage medium, when a light
reflection factor range 802 of a non-recording portion
("H" portion") of the "H-L" recording film is made
coincident with a light reflection factor range 804 of
a one-sided single layer in the read-only type
information storage medium, a reproducing circuit of
the information reproducing apparatus can be used in
common to be well compatible with the read-only type
information storage medium, and thus, the information
reproducing apparatus can be produced inexpensively.
Measurement has been carried out while producing the
"H-L" recording film and the "L-H" recording film under
a variety of changed manufacturing conditions, in order
to facilitate price reduction of a medium while
improving the manufacturing performance of the
recording film. As a result, the lower limit value (3
of the light reflection factor of the non-recording
portion ("L" portion) of the "L-H" recording film is
set to 18%, and the upper limit value y is set to 32%;
and the lower limit value 8 of the light reflection
factor of the non-recording portion ("H" portion) of
the "H-L" recording film is set to 40%, and the upper
limit value e is set to 85%.
FIGS. 23 and 24 show reflection factors at a nonrecording
position and a recorded position in a variety
of recording films in the present embodiment. In the
case where an H format has been employed (refer to
"Chapter 7: Description of H Format"), an optical
reflection factor range at the non-recording portion is
specified as shown in FIG. 22, whereby a signal appears
in a same direction in an emboss area (such as system
leas-in area SYLDI) and a recording mark area (data
lead-in area DTLDI, data lead-out area DTLDO, or data
area DTA) in the "L-H" recording film while a groove
level is defined as a reference. Similarly, in the "HL"
recording film, while a groove level is defined as a
reference, a signal appears in an opposite direction in
an emboss area (such as system lead-in area SYSDI) and
a recording mark area (data lead-in area DTLDI, data
lead-out area DTLDO, or data area DTA). Utilizing this
phenomenon, a detecting circuit design corresponding to
the "L-H" recording film and "H-L" recording film is
facilitated in addition to use for recording film
identification between the "L-H" recording film and the
"H-L" recording film. In addition, the reproduction
signal characteristics obtained from a recording mark
recorded on the "L-H" recording film shown in the
present embodiment is adjusted to conform to signal
characteristics obtained from the "H-L" recording film
to meet formulas (20) to (23). In this manner, in the
case of using either one of the "L-H" recording film
and the "H-L" recording film, the same signal processor
circuit can be used, and the signal processor circuit
can be simplified and reduced in price.
5-2) Characteristics of light absorption spectra
relating to "L-H" recording film in the present
embodiment
As has been described in "3-4) Description of
characteristics relating to "H-L" recording film in the
present embodiment, the relative absorbance in an
unrecorded area is basically low in the "H-L" recording
film, and thus, when reproduction light has been
irradiated at the time of reproduction, there occurs an
optical characteristic change generated by absorbing
energy of the reproduction light. Even if an optical
characteristic change (update of recording action) has
occurred after the energy of the reproduction light has
been absorbed in a recording mark having high
absorbance, a light reflection factor from the
recording mark is lowered. Thus, reproduction signal
processing is less affected because such a change works
in a direction in which an amplitude of a reproduction
signal (In = IHH ~ ^IIL.) °f tne reproduction signal
increases.
In contrast, the "L-H" recording film has optical
characteristics that "a light reflection factor of an
unrecorded portion is lower than that in a recording
mark". This means that, as is evident from the
contents described with respect to FIG. 2B, the
absorbance of the unrecorded portion is higher than
that in the recording mark. Thus, in the "L-H"
recording film, signal degradation at the time of
reproduction is likely to occur as compared with the
"H-L" recording film. As described in "3-2-B] Basic
characteristics common to organic dye recording
material in the invention", there is a need for
improving reliability of reproduction information in
the case where reproduction signal degradation has
occurred due to ultraviolet ray or reproduction light
irradiation".
As a result of checking the characteristics of an
organic dye recording material in detail, it has been
found that a mechanism of absorbing the energy of
reproduction light to cause an optical characteristic
change is substantially analogous to that of an optical
characteristic change due to ultraviolet ray
irradiation. As a result, if there is provided a
structure of improving durability relevant to
ultraviolet ray irradiation in an unrecorded area,
signal degradation at the time of reproduction hardly
occurs. Thus, the present embodiment is featured in
that, in the "L-H" recording film, a value of Xmax
write (maximum absorption wavelength which is the
closest to wavelength of recording light) is longer
than a wavelength of recording light or reproduction
light (close to 405 nm). In this manner, the
absorbance relevant to the ultraviolet ray can be
reduced, and the durability relevant to ultraviolet ray
irradiation can be significantly improved. As is
evident from FIG. 26, a difference in absorbance
between a recorded portion and an unrecorded portion in
the vicinity of A,max Write ^s small, and a degree of
reproduction signal modulation (signal amplitude) in
the case where the wavelength light in the vicinity of
max write is reduced. In view of a wavelength change
of a semiconductor laser light source, it is desirable
that a sufficiently large degree of reproduction signal
modulation (signal amplitude) be taken in the range of
355 nm to 455 nm. Therefore, in the present
embodiment, a design of a recording film 3-2 is made so
that a wavelength of A.max write exists out of the range
of 355 nm to 455 nm (i.e., at a longer wavelength than
455 nm).
FIG. 25 shows an example of light absorption
spectra in the "L-H" recording film in the present
embodiment. As described in "5-1) Description of
features relating to "L-H" recording film, a lower
limit value (3 of a light reflection factor at a nonrecording
portion ("L" section) of the "L-H" recording
film is set to 18%, and an upper limit value y is set
to 32% in the present embodiment. From 1 - 0.32 =
0.68, in order to meet the above condition, it is
possible to intuitively understand whether or not a
value A14Q5 °f ^he absorbance in an unrecorded area at
405 nm should meet:
A1405 68% (36)
Although the light reflection factor at 405 nm of
the light reflection layer 4-2 in FIGS. 2A and 2B is
slightly lowered than 100%, it is assumed that the
factor is almost close to 100% for the sake of
simplification. Therefore, the light reflection factor
when absorbance Al = 0 is almost 100%. In FIG. 25, the
light reflection factor of the whole recording film at
a wavelength of A,max Write is designated by
write- At this time, assuming that the light
reflection factor is zero (R-rnax write 0) / formula
(36) is derived. However, in actuality, the factor is
not set to "0", and thus, it is necessary to drive a
severer formula. A severe conditional formula for
setting the upper light value y of the light reflection
factor of the non-recording portion '"L" portion) of
the "L-H" recording film to 32% is given by:
1 - A1405 x (1 - R^max write) °-32 (37)
In a conventional write-once type information
storage medium, only the "H-L" recording film is used,
and there is no accumulation of information relating to
the "L-H" recording film. However, in the case of
using the present embodiment described later in "5-3)
Anion portion: azo metal complex + cation portion: dye"
and "5-4) Using "copper" as azo metal complex + center
metal", the most severest condition which meets formula
(37) is obtained as:
A1405 80% (38)
In the case of using an organic dye recording
material described later in the embodiment, when an
optical design of a recording film is made including a
margin such as a characteristic variation at the time
of manufacture or a thickness change of the recording
layer 3-2, it has been found that a minimum condition
which meet the reflection factor described in the
section "Description of featured relating to "L-H"
recording film" in the present embodiment:
A1405 > 40% (39)
may be met. Further, by meeting either of:
A1355 > 40% (40)
A1455 > 40% (41)
it is possible to ensure stable recording
characteristics or reproduction characteristics even if
a wavelength of a light source is changed in the range
of 355 nm to 405 nm or in the range of 405 ran to 455 nm
(in the range of 355 nm to 455 nm in the case where
both of the formulas are met at the same time) .
FIG. 26 shows a light absorption spectrum change
after recorded in the "L-H" recording film according to
the present embodiment. It is considered that a value
of a maximum absorption wavelength Xlmax in a recording
mark deviates from a wavelength of lmax write' anc* an
inter-molecular array change (for example, an array
change between azo metal complexes) occurs. Further,
it is considered that a discoloring action (cutting of
local electron orbit (local molecular link
dissociation) ) occurs in parallel to a location in
which both of the absorbance in location of ^lmax
the absorbance Al at 405 nm are lowered and the
light absorption spectra spreads itself.
In the "L-H" recording film according to the
present embodiment as well, by meeting each of formulas
(20), (21), (22), and (23), the same signal processor
circuit is made available for both of the "L-H"
recording film and the "H-L" recording film, thereby
promoting simplification and price reduction of the
signal processor circuit. In formula (20), when:
is modified,
IllH IllL/0-6 (43)
is obtained. As described previously, in the
present embodiment, a lower limit value p of a light
reflection factor of an unrecorded portion ("L"
portion) of an "L-H" recording film is set to 18%, and
this value corresponds to IHL- Further, conceptually,
the above value corresponds to:
IllH - 1 - Ah405 x (1 - RVax write) (44).
Thus, from formulas (43) and (44), the following
formula is established:
1 - Ah405 x (1 - RA-max write) 0.18/0.6
(45)
If 1 - RX,max write ^ ®r formula (45) is modified
as follows:
Ah405 In comparison between the above formulas (46) and
(36), it is found that the values of A14Q5 and Ah4Q5
may be seemingly set in the vicinity of 68% to 70% as
values of absorbance. Further, in view of a case in
which the value of A14Q5 is obtained in the range of
formula (39) and performance stability of a signal
processor circuit, a sever condition is obtained as:
Ah405 If possible, it is desirable to meet;
Ah405 0.3 (48)
5-3) Anion portion: Azo metal complex + cation
portion: dye
A description will be specifically given with
respect to an organic dye material in the present
embodiment having characteristics described in "5-1)
Description of characteristics relating to "L-H"
recording film in the present embodiment", the present
embodiment meeting a condition shown in "5-2)
Characteristics of optical absorption spectra relating
to "L-H" recording film" in the present embodiment".
The thickness of the recording layer 3-2 meets the
conditions shown in formulas (3), (4), (27), and (28),
and is formed by spinner coating (spin coating). For
comparison, a description will be given by way of
example. A crystal of a "salt" is assembled by "ion
coupling" between positively charged "sodium ions" and
negatively charged "chloride ions". Similarly, in
polymers as well, there is a case in which a plurality
of polymers are combined with each other in the form
close to "ion coupling", forming configuring an organic
dye material. The organic dye recording film 3-2 in
the present embodiment is composed of a positively
charged "cation portion" and a negatively charged
"anion portion". In particular, the above recording
film is technically featured in that: coupling
stability is improved by utilizing a "dye" having
chromogenic characteristics for the positively charged
"cation portion" and utilizing an organic metal complex
for the negatively charged "anion portion"; and there
is met a condition that "8] an electron structure in a
chromogenic area is stabilized, and structural
decomposition relevant to ultraviolet ray or
reproduction light irradiation hardly occurs" shown in
"3-2-B] Basic feature common to organic dye recording
material in the present embodiment". Specifically, in
the present embodiment, an "azo metal complex" whose
general structural formula is shown in FIG. 3 is
utilized as an organic metal complex. In the present
embodiment which comprises a combination of an anion
portion and a cation portion, cobalt or nickel is used
as a center metal M of this azo metal complex, thereby
enhancing optical stability. There may be used:
scandium, yttrium, titanium, zirconium, hafnium,
vanadium, niobium, tantalum, chrome, molybdenum,
tungsten, manganese, technetium, rhenium, iron,
ruthenium, osmium, rhodium, iridium, palladium,
platinum, copper, silver, gold, zinc, cadmium, or
mercury and the like without being limited thereto. In
the present embodiment, as a dye used for the cation
portion, there is used any of a cyanine dye whose
general structural formula is shown in FIG. 27; a
styril dye whose general structural formula is shown in
FIG. 28; and a monomethine cyanine dye whose general
structural formula is shown in FIG. 29.
Although an azo metal complex is used for the
anion portion in the present embodiment, a formazane
metal complex whose general structural formula is shown
in FIG. 30 may be used without being limited thereto,
for example. The organic dye recording material
comprising the anion portion and cation portion is
first powdered. In the case of forming the recording
layer 3-2, the powdered organic dye receding material
is dissolved in organic solvent, and spin coating is
carried out on the transparent substrate 2-2. At this
time, the organic solvent to be used includes: a
fluorine alcohol based TFP (tetrafluoro propanol) or
pentane; hexane; cyclohexane; petroleum ether; ether or
analogous, nitrile or analogous, and any of a nitro
compound or sulfur-containing compound or a combination
thereof.
5-4) Using "copper" as azo metal complex + center
metal
FIGS. 65 and 66 each show an example of a light
spectrum change before and after recording (forming a
recording mark) in an "H-L" recording film and an "L-H"
recording film using an optical characteristic change
according to the present embodiment as a principle of
recording. A wavelength of X,max write before recording
(in an unrecorded area) is defined as.bmax Write; a
half value width of a light absorption spectrum (b)
around this X,max write (a width of a wavelength area
meeting a range of "A 0.5" when the absorbance A at
krnax write is "1") is defined as Was; and a wavelength
°f ^max write °f a light absorption spectrum (a) after
recorded (in a recording mark) is defined as ^.amax
write- The recording film 3-2 having the
characteristics shown in FIGS. 65 and 66 utilizes a
"change of an electron structure (electron orbit)
relevant to elements which contribute to a chromogenic
phenomenon and a "molecular structure change in
molecules" from among the principles of recording shown
in [a] of "3-2-B] Basic characteristics common to
organic dye recording material in the invention". If
there occurs a "change of an electron structure
(electron orbit) relevant to electrons which contribute
to a chromogenic phenomenon", for example, the
dimensions or structure of the light emitting area 8 as
shown in FIG. 3 changes. For example, if dimensions of
the light emitting area 8 change, the resonant
absorption wavelength of the local electrons also
changes, and thus, the maximum absorption wavelength of
light absorption spectra changes from raax Write to
max write- Similarly, if a "molecular structure
change in molecules" occurs, a structure of the light
emitting area 8 also changes, and thus, the maximum
absorption wavelength of the light absorption spectra
also changes. When a change amount of the maximum
absorption wavelength is defined as AA,max, the
following relationship is established:
A^max - I amax write ~"max write I (49)
When the maximum absorption wavelength of the
light absorption spectra thus changes, the half value
width Was of the light absorption spectra also changes
concurrently. A description will be given with respect
to an effect on a reproduction signal obtained from a
recording mark position when the maximum absorption
wavelength of the light absorption spectra and the half
value width Was of the light absorption spectra have
thus changed at the same time. The light absorption
spectra in a pre-recording/unrecorded area are
represented as (b) in FIG. 65 (FIG. 66), and thus, the
absorbance with a reproduction light beam having 405 nm
is obtained as Ah4Q5 (Alos) If only the maximum
absorption wavelength changes to Xamax write as optical
spectra after recorded (in recording mark) and a change
of the half value width Was has not occurred, the light
absorption spectra are theoretically obtained as shown
in (c) of FIG. 65 (FIG. 66). Then, the absorbance with
a reproduction light beam having 405 nm changes to
A405- However, in actuality, the half value width
changes, and the absorbance after recorded (in
recording mark) is obtained as A14Q5 (Ah4Q5). A change
amount |A]_4Q5 - Ah4Q5 of the absorbance before and
after recorded is proportional to a reproduction signal
amplitude value. Thus, in the example shown in FIG. 65
(FIG. 66), the maximum absorption wavelength change and
the half width value change work as an offset action
relevant to an increase of the reproduction signal
amplitude. Therefore, there occurs a problem that a
C/N ratio of a reproduction signal is impaired. A
first application example of the present embodiment for
solving the above problem is featured in that the
characteristics of the recording layer 3-2 is set
(film-designed) so that a maximum absorption wavelength
change and a half value width change work relevant to
an increase of the reproduction signal amplitude in a
synergetic manner. That is, as is easily predicted
from the change shown in FIG. 65 (FIG. 66), the
characteristics of the recording layer 3-2 is set
(film-designed) so that a change occurs in a direction
in which a half value width widens independent of a
moving direction of A,amax Write after recorded relevant
to bmax write before recorded in the "H-L" recording
film or in a direction in which the half value width
narrows independent of a moving direction of A,amax
write after recorded relevant to bmax write before
recorded in the "L-H" recording film.
Now, a second application example in the present
embodiment will be described here. As described
previously, there is a case in which the C/N ratio of
the reproduction signal is lowered by offsetting a
difference between Ah4Q5 and A1405 due to the maximum
absorption wavelength change and the change of the half
value width Was. Further, in the above first
application example or the embodiment shown in FIG. 65
or FIG. 66, the maximum absorption wavelength change
and the half value width Was of the light absorption
spectra change at the same time, a value of the
absorbance "A" after recorded (in recording mark) is
affected by both of the maximum absorption wavelength
change amount AXmax and the half value width change
amount. When the write-once type information storage
medium 12 has been mass-produced, it is difficult to
precisely control values of both of the maximum
absorption wavelength change amount A^max and the half
value width change amount. Thus, when the information
is recorded in the mass-produced write-once type
information storage medium 12 has been recorded, a
fluctuation of the reproduction signal amplitude
increases. Then, the reliability of the reproduction
signal is lowered when the signal has been reproduced
by the information reproducing apparatus shown in
FIG. 11. In contrast, the second application example
in the present embodiment is featured in that a
material of which the maximum absorption wavelength
does not change between before and after recorded
(between the recording mark and the unrecorded area).
Therefore, a fluctuation of values of the absorbance
"A" after recorded (in recording mark) is suppressed
and a fluctuation between the individuals of the
reproduction signal amplitude from the above value
fluctuation is reduced, whereby the reliability of the
reproduction signal has been improved. In this second
application example, the maximum absorption wavelength
does not change between before and after recording (in
recording mark and in unrecorded area), and the value
of the absorbance "A" is determined depending on only
the spread of the light absorption spectra before and
after recording (in recording mark and in unrecorded
area). When a large number of write-once type
information storage mediums 12 have been mass-produced,
it is sufficient if only the spread of the light
absorption spectra before and after recorded (in
recording mark and in unrecorded area) is controlled,
and thus, a fluctuation in characteristics between
mediums can be reduced. Even if a contrivance is made
so that a maximum absorption wavelength before and
after recording (in recording mark and in unrecorded
area) does not change, strictly, it is difficult to
completely match the values of A,bmax write anc-amax
write other, as shown in FIG. 68. The half value
width Was of the light absorption spectra around Xbmax
write shown in FIG. 65 or 66 is often included in the
range of 100 nm to 200 nm in a general organic dye
recording material. Therefore, if the value of the
maximum absorption wavelength change amount AXmax
exceeds 100 nm, it is possible to easily predict from
FIG. 65 or 66 that there occurs a large difference
between the absorbance Ah4Q5 (A14Q5) obtained from the
characteristics of item (b) and the absorption A*4Q5
obtained from the characteristics of item (c).
Accordingly, the fact that "the maximum absorption
wavelength does not change" as the second application
example mans that the following condition is met:
AA,max Further, when a condition that the maximum
absorption wavelength change amount AXmax is 1/3 of the
value obtained by formula (50), i.e.,
AXmax a difference between the absorbance Ah4Q5 (A14Q5)
obtained from the characteristics of item (b) and the
absorption A*4Q5 obtained from the characteristics of
item (c) is very small, and a fluctuation in
reproduction signal characteristics between the mediums
can be reduced.
FIG. 68 shows the "L-H" recording film
characteristics, which meet formula (50) or formula
(51). The light absorption spectra before recorded (in
unrecorded area) are obtained as wide spectra as shown
in the characteristic (b) of FIG. 68, and the
absorbance Ah4Q5 at a reproduction wavelength of 405 nm
is obtained as a sufficient small value. The
absorbance Ah405 after recorded (in recording mark)
narrows in width as shown in the characteristic (a) of
FIG. 68, and the absorbance AlQS at a reproduction
wavelength of 405 nm rises.
In order to meet formula (50) or formula (51), the
present embodiment utilizes an "orientation change in
molecules" in item [a] of "3-2-B] Basic characteristics
common to organic dye recording material in the
invention" as a principle of recording. In the azo
metal complex shown in FIG. 3, a plurality of benzene
nucleus rings are located on the same plane because the
benzene nucleus rings are radically coupled with each
other. That is, in FIG. 3, four benzene nuclear rings
which exist more upwardly than the center metal M forms
an U (up-side) plane which the benzene nucleus group
produced; and four benzene nuclear rings which exist
more downwardly than the center metal M forms a D
(down-side) plane which the benzene nucleus group
produced.
A mutually parallel relationship is always
maintained between the above U plane and D plane in any
case (irrespective of whether pre-recording or postrecording
may be). Side chain groups of Rl and R3 are
arranged in a form orthogonal to the above U plane and
D plane. Ion coupling is carried out between the
center metal atom M and the oxygen atom 0, and a plane
formed by a line segment for connecting 0-M-O is
located in parallel to the above U plane and D plane.
The light emitting area 8 surrounded in a round area
shown in FIG. 3 has such a three-dimensional structure.
For further description, a direction oriented from a
direction of R4 to a direction of R5 in the U plane is
tentatively defined as a "Yu direction", and a
direction oriented from a direction of R4 to a
direction of R5 in the D plane is defined as a "Yd
direction". Orientation coupling is carried out
between a nitrogen atom N included in the U plane or D
plane and the center metal atom M sandwiched between
these two planes so that a position of the nitrogen
atom N around the center metal atom M can be rotated.
That is, a structure is provided such that the Yd
direction can be rotated with respect to the Yu
direction while a mutually parallel relationship is
maintained between the above U plane and D plane. In
the azo metal complex shown in FIG. 3, the Yu direction
and Yd direction can be parallel to each other, as
shown in FIG. 67A (the orientations can be made
identical or opposite to each other as shown in
FIG. 67A); and the Yu direction and Yd direction can be
in a skew position relationship as shown in FIG. 67B.
Of course, an arbitrary angle relationship between
FIGS. 67A and 67B can be also established. As
described previously, the side chain groups of Rl and
R3 are arranged in a form orthogonal to the above U
plane and D plane. Thus, in the structure of FIG. 67A,
collision is likely to occur between the side chain
group of Rl or R3 and another side chain group of R4 or
the like. Therefore, as shown in FIG. 67B, a time
point at which the Yu direction and Yd direction are in
a skew position relationship (when the U plane is seen
from far above, the Yu direction and Yd direction are
seen as if it were orthogonal to each other) is the
most stable in a structural point of view. The light
absorption wavelength in the light emitting area 8 when
the state shown in FIG. 67B is established coincides
with a value of Xamax write = ^bmax write shown in
FIG. 68. If the relationship between the Yu direction
and Yd direction deviates from the state shown in
FIG. 67B, the electron structure in the light emitting
area 8 and the local distance of light absorption
electrons (the size of local area) slightly change, and
the light absorption wavelength deviates from the value
of amax write = bmax write- BY means of spinner
coating, a relationship between the above Yu direction
and Yd direction is arbitrarily oriented in the
recording layer 3-2 (in unrecorded state) immediately
after formed on the transparent substrate 2-2.
Therefore, the distribution width of light absorption
spectra widens as shown in characteristic (b) of
FIG. 68. In order to form a recording mark, when a
temperature in the recording layer 3-2 is locally
risen, a molecular orientation moves because of a high
temperature, and finally, an almost stable state shown
in FIG. 67B is established in a structural point of
view. Then, the electron structures in the light
emitting area 8 coincide with each other anywhere in
the recording mark, and the current spectra changes to
narrow light absorption spectra in width, as shown in
characteristic (a) of FIG. 68. As a result, the
absorbance at a reproduction wavelength (for example,
405 nm) changes from Al^QS to Ah4Q5-
A description will be made with respect another
advantageous effect of using the light emitting area 8
in an azo metal complex. A dye is utilized for a
cation portion in the case of utilizing a combination
of the anion portion and the cation portion described
previously. Although the chromogenic area in each of
the dyes shown in FIGS. 27 to 29 occupies a portion in
each of the dye structures, a relative occupying
capacitance of the chromogenic area in the recording
layer 3-2 is decreased by combining this area with an
anion portion which does not contribute to the
chromogenic area. Therefore, a light absorption
sectional area is relatively lowered, and a molar
molecule light absorption coefficient is lowered. As a
result, a value of the absorbance at a position of A,max
write shown in FIG. 25 is reduced, and recording
sensitivity is lowered. In contrast, in the case of
utilizing the chromogenic characteristics at the
periphery of the center metal of an azo metal complex
itself described here, the azo metal complex itself
emits light, and thus, there does not exist a redundant
portion which does not contribute to a chromogenic area
such as the anion portion described previously.
Therefore, there is no unnecessary factor that the
relative occupying capacitance of the chromogenic area
decreases. Further, as shown in FIG. 3, the occupying
capacitance of the light emitting area 8 in the azo
metal complex is wide, and thus, the light absorption
sectional area increases, and a value of the molar
molecule light absorption coefficient rises. As a
result, there is provided advantageous effect that the
value of the absorbance at a position of Xmax write
shown in FIG. 25 increases, and the recording
sensitivity is improved.
The present embodiment is featured in that the
structural stability of the chromogenic area has been
achieved by optimizing the center metal of the azo
metal complex as a specific method for "8] stabilizing
an electron structure in a chromogenic area so that
structural decomposition relevant to ultraviolet ray or
reproduction light irradiation hardly occurs" described
in "3-2-B] Basic characteristics common to organic dye
recording material in the invention".
It is known that metal ions have their unique
ionization tendency. These metal atoms are arranged in
stronger order of ionization tendency, i.e., Na > Mg >
Al > Zn > Fe > Ni > Cu > Hg > Ag > Au. The ionization
tendency of the metal atoms represents "nature of metal
radiating electrons to form positive ions".
After a variety of metal atoms has been
incorporated as the center metal of the azo metal
complex having the structure shown in FIG. 3, where
reproduction stability (stability of chromogenic
characteristics when a light beam in the vicinity of
405 nm is repeatedly irradiated with reproduction
power) is repeatedly checked, it has been found that
the metal atoms with high ionization tendency radiates
electrons more remarkably and are easily decoupled; and
the light emitting area 8 is easily destroyed. As a
result of a number of tests, in order to ensure
structural stabilization of the chromogenic area, it
has been found desirable to use a metal material (Ni,
Cu, Hg, Ag, Au) after nickel (Ni) as the center metal.
Further, from the viewpoint of "structural stability of
high chromogenic area", "low price", and "use safety",
it is the most desirable to use copper (Cu) as the
center metal as the present embodiment. In the present
embodiment, any of CH3, CxHy, H, Cl, F, NC>2, S02, and
S02NHCH3 is used as Rl, R2, R3, R4, or R5 which is a
side chain shown in FIG. 3.
Now, a description will be given with respect to a
method for forming an organic dye recording material
having a molecular structure shown in FIG. 3 as the
recording layer 3-2 on a transparent substrate 2-2.
The powdered organic dye recording material of 1.49 g
is dissolved in 100 nm of TFP (tetrafluoro propanol)
which is a fluorine alcohol based solvent. The above
numeric value denotes that 1.4 wt% is obtained as a
mixture ratio, and an actual use amount changes
depending on a manufacture amount of the write-once
type information storage medium. It is desirable that
the mixture ratio ranges from 1.2 wt% to 1.5 wt%. As a
solvent, it is conditionally mandatory that a surface
of the transparent substrate 2-2 made of a
polycarbonate resin is not dissolved, and the above
described alcohol based solvent is used. Because the
above TFP (tetrafluoro propanol) has polarity, the
solubility of the powdered organic dye recording
material is improved. While the transparent substrate
2-2 on a spindle motor is rotated, the organic dye
recording material dissolved in the solvent is applied
to the center part of the transparent substrate 2-2
until the solvent has evaporated after the material has
been spread by utilizing a centrifugal force, and then,
the recording layer 3-2 is compressed in accordance
with a baking process for increasing the entire
temperature.
FIG. 69 shows a third application example in which
a basic principle of the second application example in
the present embodiment is applied to the "H-L"
recording film. The maximum absorption wavelength
amax write °f absorption spectra (a) after recorded
(in recording mark) is equalized with respect to the
maximum absorption wavelength A,bmax Write °f absorption
spectra (b) before recorded (in unrecorded area). As
an example of a specific organic dye material which
achieves the third application example, an azo metal
complex is used for an anion portion. For a cation
portion, there is used an "anion/cation type organic
dye recording material" utilizing dye molecules having
an absorption wavelength A,bmax write on a shorter
wavelength side than a reproduction signal wavelength
(for example, 405 nm), as shown in FIG. 69. In this
case, in the azo metal complex shown in FIG. 3, at an a
position or a y position in the D plane, which a
benzene nucleus group produces and a P position or a 8
position in the U plane which a benzene nucleus group
produces, color dye molecules (positively charged
cation portion) are allocated by an inter-ion force.
As in the second application example, a principle of
changing (recording) the light absorption spectra
before and after recorded while keeping unchanged the
maximum absorption wavelength A,bmax write °f the light
absorption spectra (b) before recorded (in unrecorded
area) and the maximum absorption wavelength A,amax Write
of the light absorption spectra (a) after recorded (in
recording mark) utilizes rotation between the U plane
(Yu direction) which the benzene nucleus group produces
and the D plane (Yd direction) which the benzene
nucleus group produces. Further, in the third
application example, the electron coupling force in the
light emitting area 8 is improved, whereby "degradation
of an electron structure (electron orbit) with respect
to electrons which contribute to a chromogenic
phenomenon" hardly occurs. As a result, an area in the
absorption spectra (b) before recorded (in unrecorded
area) (an integration result in spectra wavelength
direction) can be adjusted to conform to an area in the
absorption spectra (a) after recorded (in receding
mark). In this manner, the absorbance "A" at the
maximum absorption wavelength A,amax write in tne
absorption spectra (a) after recorded (in recording
mark) becomes greater than the absorbance "1" at the
maximum absorption wavelength ?ibmax wrj_te before
recorded (in unrecorded area), and a value of A14Q5
rises more significantly than a value of Ah4Q5, as
shown in FIG. 69.
In the case where degradation in the light
emitting area 8 such as discoloring action does not
occur, the area in the absorption spectra before and
after recorded (the integration result in the spectra
wavelength direction) is kept unchanged. Thus, the
absorbance Aamax in the maximum absorption wavelength
amax write increases with a decrease in the width of
the absorption spectra before and after recorded. When
a difference clearly occurs between the value of the
absorbance Al^gs and the value of Ah4Q5 at the
reproduction wavelength of 405 nm (when a reproduction
signal can be detected at a good C/N ratio), from
FIG. 69, it is found necessary to meet a condition that
the value of the absorbance Aamax in the maximum
absorption wavelength Xamax write ^s:
Aamax 1-2 (52)
Further, in order to stably ensure the reliability
of reproduction of a detection signal, it is necessary
to meet a condition:
Aamax > 1.5 (53)
Although there has been shown an example of
providing a structure in which an azo metal complex is
utilized for an anion portion and dyes are utilized for
a cation portion as a specific organic dye recording
material which achieve the third application example,
the invention (third application example) include an
organic dye recording material having "H-L" recording
characteristics; meeting formula (50) or formula (51)
with respect to the maximum absorption wavelength
change amount before and after recorded; and changing
the absorbance at the maximum absorbance wavelength
without being limited thereto, as the specific organic
dye recording material which achieves the third
application example.
Further, a fourth application example is shown in
FIG. 70. In a phase change recording film, "atoms are
allocated in order (in crystalline state) before
recorded", and "atoms are arranged in random (in
amorphous state) after recorded". In the fourth
application example, a feature of this phase change
recording film is combined with a feature that "the
maximum absorption wavelength does not change before
and after recorded" shown in the second application
example. Although a specific organic dye recording
material in the fourth application example has a
structure of utilizing the azo metal complex shown in
the third application example for an anion portion and
dyes for a cation portion as a specific organic
recording material in the fourth application example,
the detailed contained atoms, these application
examples are different from each other in terms of
detailed contained atoms, detailed intra-molecular
structure, or a method for manufacturing the recording
layer 3-2. That is, a time required for solidification
of the recording layer 3-2 is taken by using an organic
solvent which hardly evaporates after applying an
organic dye recording material dissolved in an organic
solvent on the transparent substrate 2-2 by spinner
coating, or alternatively, a temperature of the
transparent substrate 2-2 is increased in advance at
the time of the application, and then, the temperature
of the transparent substrate 2-2 is slowly decreased at
the time of evaporation of an organic solvent, whereby
a contrivance is made so that the intra-molecular (or
inter-molecular) orientation or array can be easily
arranged in order at the stage of the solidification of
the recording layer 3-2. As a result, as shown in
characteristic (b) of FIG. 70, the width of the light
absorption spectra before recorded (in unrecorded area)
becomes narrow. Next, contrivance is made to apply a
recording pulse at the time of recording (for example,
after the inside of the recording layer 3-2 has locally
exceeded an optical characteristic change temperature,
the width of the recording pulse is narrowed instead of
increasing the height of the recording pulse at the
time of applying the same energy so as to provide rapid
cooling), and the intra-molecular (or inter-molecular)
orientation or array after recorded (in recording mark)
is arranged in random. As a result, the width of the
light absorption spectra after recorded (in recording
mark) widens as shown in characteristic (a) of FIG. 70.
A large difference in absorbance "A" before and after
recorded is produced by adjusting a reproduction light
wavelength to conform to a lower end position of the
light absorption spectra. Although an example of
providing a structure in which an azo metal complex is
utilized for an anion portion and dyes are utilized for
a cation portion as a specific organic dye recording
material which achieve the fourth application example,
the invention (fourth application example) include an
organic dye recording material having "H-L" recording
characteristics; meeting formula (50) or formula (51)
with respect to the maximum absorption wavelength
change amount before and after recorded; and changing
the absorbance at the maximum absorbance wavelength
without being limited thereto, as the specific organic
dye recording material which achieves the fourth
application example.
Chapter 6: Description Relating to Pre-groove
shape/pre-pit shape in coating type organic dye
recording film and on light reflection layer interface
6-1) Light reflection layer
As described in "Chapter 0: Description of
Relationship between Use Wavelength and the Present
Embodiment", the present embodiment assumes a range of
355 nm to 455 nm in particular around 405 ran. When the
metal materials each having a high light reflection
factor at this wavelength bandwidth are arranged in
order from the highest light reflection factor, Ag is
in the order of around 96%; Al is in the order of
around 80%, and Rh is in the order of around 80%. In a
write-one type information storage medium using an
organic dye recording material, as shown in FIG. 2B,
the reflection light from the light reflection layer
4-2 is a standard, and thus, the light reflection layer
4-2 requires a high light reflection factor in
characteristics. In particular, in the case of the "HL"
recording film according to the present embodiment,
the light reflection factor in an unrecorded area is
low. Thus, if the light reflection factor in the light
reflection layer 4-2 simplex is low, in particular, a
reproduction signal C/N ratio from a pre-pit (emboss)
area is low, lacking the stability at the time of
reproduction. Thus, in particular, it is mandatory
that the light reflection factor in the light
reflection layer 4-2 simplex is high. Therefore, in
the present embodiment, in the above wavelength
bandwidth, a material mainly made of Ag (silver) having
the highest reflection factor is used. As a material
for the light reflection layer 4-2, there occurs a
problem that "atoms easily move" or "corrosion easily
occurs" if silver is used alone. To solve the first
problem, when partial alloying is carried out by adding
other atoms, silver atoms hardly move. In the first
embodiment in which other atoms are added, the light
reflection layer 4-2 is made of AgNdCu according to the
first embodiment. AgNdCu is in a solid soluble state,
and thus, the reflection factor is slightly lowered
than a state in which silver is used alone. In the
second embodiment in which other atoms are added, the
light reflection layer 4-2 is made of AgPd, and an
electric potential is changed, whereby corrosion hardly
occurs in an electrochemical manner. If the light
reflection layer 4-2 corrodes due to silver oxidization
or the like, the light reflection factor is lowered.
In an organic dye recording film having a recording
film structure shown in FIG. 2B, in particular, in the
case of an organic dye recording film shown in "Chapter
3: Description of Characteristics of Organic Dye
Recording Film in the Present Embodiment", in
particular, a light reflection factor on an interface
between the recording layer 3-2 and the light
reflection later 4-2 is very important. If correction
occurs on this interface, the light reflection factor
is lowered, and an optical interface shape blurs. In
addition, the detection signal characteristics from a
track shift detection signal (push-pull signal) or a
wobble signal and a pre-pit (emboss) area are degraded.
In addition, in the case where the width Wg of the pregroove
area 11 is wider than the width Wl of the land
area, a track shift detection signal (push-pull signal)
or a wobble signal is hardly generated, thus increasing
effect of degradation of the light reflection factor on
the interface between the recording layer 3-2 and the
light reflection layer 4-2 due to corrosion. In order
to prevent degradation of the light reflection factor
on this interface, AgBi is used for the light
reflection layer 4-2 as the third embodiment. AgBi
forms a very stable phase and prevents degradation of
the light reflection factor on the above interface
because a passive coat film is formed on a surface
(interface between the recording layer 3-2 and the
light reflection layer 4-2). That is, if Bi (bismuth)
is slightly added to Ag, Bi is isolated from the above
interface, the isolated Bi is oxidized. Then, a very
fine film (passive coat film) called oxidized bismuth
is formed to function to preclude internal oxidization.
This passive coat film is formed on the interface, and
forms a very stable phase. Thus, the degradation of a
light reflection factor does not occur, and the
stability of detection signal characteristics from a
track shift detection signal (push-pull signal) or a
wobble signal and a pre-pit (emboss) area is guaranteed
over a long period of time. At a wavelength band
ranging from 355 nm to 455 nm, the silver simplex has
the highest light reflection factor, and the light
reflection factor is lowered as an additive amount of
other atoms is increased. Thus, it is desirable that
an additive amount of Bi atoms in AgBi in the present
embodiment be equal to or smaller than 5 at%. The unit
of at% used here denotes atomic percent, and indicates
that five Bi atoms exist in a total atom number 100 of
AgBi, for example. When characteristics have been
evaluated by actually producing the passive coat film,
it has found that a passive coat film can be produced
as long as an additive amount of Bi atoms is equal to
or greater than 0.5 at%. Based on a result of this
evaluation, an additive amount of Bi atoms in the light
reflection layer 4-2 in the present embodiment is
defined as 1 at%. In this third embodiment, only one
atom Bi is added, and an additive amount of atoms can
be reduced as compared with AgNdCu according to the
first embodiment (a case in which two types of atoms Nd
and Cu is added in Ag), and AgBi can increase the light
reflection factor more significantly than AgNdCu. As a
result, even in the case of the "H-L" recording film
according to the present embodiment or in the case
where the width Wg of the pre-groove area 11 is wider
than the with Wl of the land area, as shown in FIGS. 8B
and 8C, a detection signal can be stably obtained from
a track shift detection signal (push-pull signal) or a
wobble signal and a pre-pit (emboss) area with high
precision. The third embodiment is not limited to
AgBi, and a ternary system including AgMg, AgNi, AgGa,
AgNx, AgCo, AgAl or the atoms described previously may
be used as a silver allow which produces a passive coat
film. The thickness of this light reflection layer 4-2
is set in the range of 5 nm to 200 nm. If the
thickness is smaller than 5 nm, the light reflection
layer 4-2 is not uniform, and is formed in a land
shape. Therefore, the thickness of the light
reflection layer 4-2 is set to 5 nm. When an AgBi film
is equal to or smaller than 80 nm in thickness, the
film permeates to its back side. Thus, in the case of
a one-sided single recording layer, the thickness is
set in the range of 80 nm to 200 nm, and preferably, in
the range of 100 nm to 150 nm. In the case of a onesided
double recording layer, the thickness is set in
the range of 5 nm to 15 nm.
Write-once type information storage mediums having
high density and used for a method for recording
information in a storage medium which uses an organic
dye material, the storage mediums carrying out
recording and reproduction by using a light beam of
620 nm or less in wavelength, include: a one-sided
single-layer medium as shown in FIG. IB; and a onesided
double-layer medium as shown in FIG. 1C. The
one-sided single-layer medium is sequentially composed
of a transparent substrate 2-2, a recording layer
(recording film) 3-2, and a light reflection layer
(light reflection film) 4-2 from a light incident side.
A storage medium (referred to as LO) close to the light
incident side of the one-sided double-layer medium is
sequentially composed of the transparent substrate 2-2,
the recording layer 3-2, and a semipermeable light
reflection layer 4-2 from the light incident side. A
storage medium (referred to as LI) distant from the
light incident side is sequentially composed of the
recording layer 3-2, the light reflection layer 4-2,
and the substrate 2-2 from the light incident side. A
layer for optically separating two layers, a so called
interlayer separating layer (interlayer separation
film) 7-1, is formed between the medium LO and the
medium LI. In addition, the transparent substrate 2-2
of the medium LI may not be always transparent, and an
opaque substrate may be used. In the following
description, in the case where a layer is merely
referred to as a light reflection layer, it denotes a
generic name of the light reflection layer 4-1 and the
semipermeable light reflection layer 4-2. In order to
obtain high signal characteristics on an entire surface
of an optical storage medium, there is a need for
providing a high reflectivity in a state in which the
transparent substrate 2-2, the recording layer 3-2, and
the light reflection layer 4-2 have been laminated.
Thus, it is desirable that a light reflection film
simplex have a high reflectivity. In order to achieve
this, a material mainly made of Ag (silver) having the
highest reflectivity is used in the above wavelength
band (405 nm and its proximity, for example, 355 nm to
455 nm).
On the other hand, as described in section 6-1),
in a silver simplex used as a material for a light
reflection film, there occurs a problem that light
reflection characteristics are changed by the fact that
"atoms easily move" and "corrosion easily occurs", and
the performance is degraded in terms of information
repetition reproduction, count, and storage service
life. As a means for solving these problems, a method
using a variety of silver alloys is conventionally
known. However, in the storage medium according to the
present invention, there is used an organic dye
recording material which has not been used
conventionally. Thus, in the conventional method, the
above-described problems have not been solved.
A conventionally known method for preventing
movement of single silver atoms in a light reflection
film includes a method for adding to silver an element
which has a pinning effect. On the other hand, there
has not been clarified an element which prevents
movement of single silver atoms without lowering a
reflectivity in the above-described wavelength band or
significantly lowering thermal characteristics. With
respect to a disclosed conventional technique, as long
as an amount of additives is not particularly large,
there is substantially no advantageous effect. On the
other hand, there are two methods for preventing
corrosion of silver in a reflection film; (1) a
electrochemical method; and (2) a method for forming a
passive coat on an interface. With respect to (1) the
electrochemical method, as long as an amount of
additives is not particularly large, there is
substantially no advantageous effect. In addition,
with respect to (2) the method for forming the passive
coat on the interface as well, there has not been
achieved a method for forming a rigid passive coat
without lowering the reflectivity in the abovedescribed
wavelength band or significantly lowering the
thermal characteristics. This is because, in order to
complete a storage medium embodiment, characteristics
greatly depend on what configuration of a storage
medium is used, and thus, it is impossible to obtain
problems to be solved and a proper means for solving
these problems merely by investigating general material
characteristics. In addition, in the case of the
present embodiment, in addition to these problems, it
has been difficult to achieve the embodiment by the use
of the organic dye recording material which has not
been used conventionally, as described below.
In order to prevent movement of single silver
atoms and prevent corrosion of silver in a reflection
film without lowering the reflectivity in the abovedescribed
waveform band or without significantly
lowering the thermal characteristics, the present
embodiment is featured by a light reflection layer of a
storage medium shown in FIGS. IB and 1C using an
organic dye material recorded with a light beam of
620 nm or less in wavelength in which prevention layers
8, 8-1, and 8-2 which prevent a characteristic change
of a light reflection layer are provided between a
light reflection layer and a recording layer. The
causes for characteristic change are movement of atoms
and reaction (corrosion). The reaction used here
includes a chemical reaction or performance degradation
caused by a light reflection layer coming into contact
with an organic dye material which is a recording film.
The prevention layer used here may not be formed to
have a finite thickness (passive coat formed on
interface), and may be formed as a layer
(electrochemical layer) having electrically different
characteristics, the layer being formed by a
semiconductor apparatus or a semiconductor device and
the like.
The light reflection layer used here is composed
essentially of silver Ag, contains at least one type of
additive elements selected from: aluminum Al; gold Au;
bismuth Bi; calcium Ca; cerium Ce, cobalt Co, gallium
Ga, lanthanum La; magnesium Mg; nitrogen N; nickel Ni;
neodium Nd; palladium Pd; yttrium Y; tungsten W, and
zirconium Zr, and ranges from 0.05 at% to 5 at% in
total of additive elements. It is impossible to avoid
entry of a very small amount of elements into Ag and
additive elements used as a base material for a
reflection film material. With respect to these
elements, even if a very small amount thereof is
detected by analysis, it is impossible to say they are
a different material. Therefore, this material is not
said to be different from the scope of the present
invention.
For example, let us consider a light reflection
layer using AgBi. AgBi forms a passive coat on a
surface (interface between recording layer 3-2 and
light reflection layer 4-2). Thus, this element forms
a very high stable phase, and prevents degradation of
the light reflectivity on the above-described
interface. That is, if a small amount of Bi (bismuth)
is added to Ag, Bi floats on the interface, and is
oxidized. Then, a very delicate film (passive coat)
called bismuth oxide is formed, and functions to stop
internal oxidization or reaction, or alternatively,
degradation of the reflection film. In addition, in a
combination with the organic dye recording material
used in the present embodiment, it has been found that
there is attained advantageous effect of preventing
movement of single silver atoms without lowering the
reflectivity in the above-described wavelength band or
significantly lowering the thermal characteristics. In
general, the concentration of additive elements in an
Ag alloy is greatly influenced by a reflectivity or
optical characteristics, thermal characteristics, and
easiness of movement of single silver atoms.
Therefore, an Ag alloy in which a concentration change
occurs is considered to be generally low in
advantageous effect of preventing movement of single
silver atoms without lowering the reflectivity or
significantly lowering the thermal characteristics. In
the present embodiment, it is considered that
advantageous effect has been attained in a
configuration which seems to have been ineffective
conventionally because a specific organic dye material
is used. Therefore, the present invention is greatly
featured by a light reflection layer of a storage
medium using an organic dye material recorded with a
light beam of 620 nm or less in wavelength in which
there is formed a prevention layer which prevents
reaction between a light reflection layer and a
recording layer caused by the light reflection layer
coming into contact with an organic dye material or a
characteristic change or degradation of an optical
reflection layer. These advantageous effects are
considered as being attained by combining the organic
dye material and the Ag alloy according to the present
embodiment.
In addition, apart from Bi, it has been found that
similar advantageous effect is attained in Ca, Ce, Co,
Ga, Ni, La, Mg, W, and Zr (elements for forming a
passive coat including Bi is referred to as additive
elements of group 1). On the other hand, in Al, Au,
Pd, Pt, and Rh (referred to as additive elements of
group 2), electrochemically advantageous effect is
strong. Thus, it is effective to use these additive
elements of group 2 in combination with the additive
elements of group 1. In addition, with respect to N
(nitrogen), a reaction product with Ag-N serves as part
of a passive coat. Thus, the passive coat may be
formed of a plurality of layers without being limited
to a single layer. In addition to the additive
elements of group 1, it is effective to add Cu, Nd, or
Y (referred to as additive elements of group 3). With
respect to group 2, group 3, and N, even if
comparatively large amounts of these elements are added
or reacted, no precipitation occurs, and solid solution
or reaction with Ag can be obtained. Thus, if an
amount of additives increases, the reflectivity or
thermal conductivity is rapidly lowered. Therefore,
careful consideration is required for the amount of
additives and adding process. Among them, for example,
in the case where AgAl is used, if an amount of
additives increases, the lowering of the reflectivity
and thermal conductivity of the reflection film becomes
very substantial.
When the content of additive elements 0.05 at% or
less, advantageous effect is low. In addition, when it
is 5 at% or more, advantageous effect is low. In the
case where an amount of additive elements is 0.05 at%
or less, in particular, performance of forming a
passive coat and preventing corrosion is lowered.
Conversely, in the case where an amount of additive
elements is 5 at% or more, the lowering of the
reflectivity and thermal characteristics becomes
substantial. The above-described amount of additive
elements denotes an amount analyzed by forming a
reflection film simplex on a substrate on which no
reaction occurs or a substrate composed of elements
separated by analysis even if a reaction occurs.
Therefore, in the storage medium, the additive elements
move from the inside of the reflection film onto an
interface of an organic dye material and the like,
thereby forming a passive coat, and thus, locally
different portions may exist. Therefore, an amount of
additive elements indicates a value obtained by
analyzing an amount added to the reflection layer
without forming a passive coat. With respect to the
concentration of the additive elements in the
reflection layer, the additive elements occasionally
move onto an interface with an opposite adhesive layer
in addition to moving onto the interface with the
organic dye recording material which is a recording
layer, thereby forming a passive coat. To which
interface a larger amount of the elements move depends
on type of organic dye recording material to be used,
Ag alloy of reflection layer to be used and type of
adhesive to be used.
6-2) Description relating to pre-pit shape in
coating type organic dye recording film and on light
reflection layer interface
In an H format according to the present
embodiment, as shown in FIGS. 35A, 35B and 35C, the
system lead-in area SYLDI is provided. In this area,
an emboss pit area 211 is provided, and, as shown in
FIGS. 71A and 71B, information is recorded in advance
in the form of a pre-bit. A reproduction signal in
this area is adjusted to conform to reproduction signal
characteristics from a read-only type information
storage medium, and a signal processor circuit in an
information reproducing apparatus or an information
recording/reproducing apparatus shown in FIG. 11 is
compatible with a read-only type information storage
medium and a write-once type information storage
medium. A definition relevant to a signal detected
from this area is adjusted to conform with a definition
of "3-4): Description of characteristics relating to
"H-L" recording film in the invention". That is, a
reproduction signal amount from the space area 14
having a sufficiently large length (11T) is defined as
IllHf and a reproduction signal from the pre-pit
(emboss) area 13 having a sufficiently large length
(11T) is defined as IHL- In addition, a differential
value between these amounts is defined as !]_]_ = IHH ~
IHL- n the present embodiment, in accordance with
the reproduction signal characteristics from the
read-only type information storage medium, the
reproduction signal in this area is set to be:
Ill/Inn 0.3 (54)
and desirably, is set to be:
I11/I11H > O-5 (55)
When a repetitive signal amplitude of the space
area 14 relevant to the pre-pit (emboss) area 13 having
a 2t length is defined as 12, the amplitude is set to
be:
I2/In > 0.5 (56)
and desirably, is set to be:
I2/In > 0.7 (57)
A description will be given with respect to a
physical condition for meeting the above formula (54)
or formula (55).
As has been described in FIG. 2B, the signal
characteristics from a pre-pit are mainly dependent on
the reflection in the light reflection layer 4-2.
Therefore, the reproduction signal amplitude value _]_
is determined depending on a step amount Hpr between
the space area 14 and the pre-pit (emboss) area 13 in
the light reflection layer 4-2. When optical
approximation calculation is made, this step amount
Hpr, with respect to a reproduction light wavelength A,
and a refractive index n32 in tne recording layer 3-2,
has the following relationship:
111 « sin2{(27i x Hpr x n32)/M (58)
From formula (58), it is found that In becomes
maximal when Hpr ^ X/(4 x n32). In order to meet
formula (54) or formula (55), from formula (58), it is
necessary to meet:
Hpr > K/ (12 x n32) (59)
and desirably,
Hpr > A,/(6 x n32) (60)
As described in "Chapter 0: Description of
Relationship between Use Wavelength and the Present
Embodiment", X = 355 nm to 455 nm is used in the
embodiment, and as described in "2-1) Difference in
Principle of Recording/Recording Film and Difference in
Basic Concept Relating to Generation of Reproduction
Signal", n32 = 1.4 to 1.9 is established. Thus, when
this value is substituted into formula (59) or formula
(60), a step is produced so as to meet a condition:
Hpr > 15.6 nm (62)
and desirably,
Hpr > 31.1 nm (63)
In the conventional write-once type information
storage medium, as shown in FIG. 71B, the thickness of
the recording layer 3-2 is small in the space area 14,
and thus, a step on an interface between the light
reflection layer 4-2 and the recording layer 3-2 is
small, and formula (62) has not successfully met. In
contrast, in the present embodiment, a contrivance has
been made to ensure that a relationship between the
thickness Dg of the recording layer 3-2 in the pre-pit
(emboss) area 13 and the thickness Dl of the recording
layer 3-2 in the space area 14 conform with a condition
described in "3-2-E] Basic characteristics relating to
thickness distribution of recording layer in the
present embodiment for definition of parameters". As a
result, as shown in FIG. 71B, a sufficiently large step
Hpr which meets formula (62) or formula (63) has been
successfully provided.
By carrying out optical approximation discussion
as described above, in the present embodiment, in order
to have sufficient resolution of a reproduction signal
so as to meet formula (56) or formula (57), a
contrivance is made so that the width Wp of the pre-pit
(emboss) area 13 is equal to or smaller than half of
track pitches as shown in FIG. 71B, and a reproduction
signal from the pre-pit (emboss) area 13 can be largely
taken.
6-3) Description relating to pre-groove shape in
coating type organic dye recording film and on light
reflection layer interface:
Chapter 7: Description of H Format
Now, an H format in the present embodiment will be
described here.
FIG. 31 shows a structure and dimensions of an
information storage medium in the present embodiment.
As embodiments, there are explicitly shown three types
of embodiments of information storage mediums such as:
- "read-only type information storage medium" used
exclusively for reproduction in which recording cannot
be carried out;
- "write-once type information storage medium"
capable of additional recording; and
- "rewritable type information storage medium"
capable of rewriting or recording any times
As shown in FIG. 31, the above three types of
information storage mediums are common to each other in
a majority of structure and dimensions. In all of the
three types of information storage mediums, from their
inner periphery side, a burst cutting area BCA, a
system lead-in area SYLDI, a connection area CNA, a
data lead-in area DTLSI, and a data area DTA have been
arranged. All the mediums other than an OPT type readonly
medium is featured in that a data lead-out area
DTLDO is arranged at the outer periphery. As described
later, in the OPT type read-only medium, a middle area
MDA is arranged at the outer periphery. In either of
the write-once type and rewritable type mediums, the
inside of this area is for read-only (additional
writing disabled). In the read-only type information
storage medium, information is recorded in the data
lead-in area DTLDI in the form of emboss (pre-pit). In
contrast, in the write-once type and the rewritable
type information storage medium, new information can be
additionally written (rewritten in the rewritable type)
by forming a recording mark in the data lead-in area
DTLDI. As described later, in the write-once type and
rewritable type information storage medium, in the data
lead-out area DTLDO, there coexist an area in which
additional writing can be carried out (rewriting can be
carried out in the rewritable type) and a read-only
area in which information is recorded in the form of
emboss (pre-pit). As described previously, in the data
area DTA, data lead-in area DTLVI, data lead-out area
DTSDO, and middle area MDA shown in FIG. 31, high
density of the information storage medium is achieved
(in particular, line density is improved) by using a
PRML (Partial Response Maximum Likelihood) method for
reproduction of signals recorded therein. In addition,
in the system lead-in area SYLDI and the system leadout
area SYLDO, compatibility with a current DVD is
realized and the stability of reproduction is improved
by using a slice level detecting system for
reproduction of signals recorded therein.
Unlike the current DVD specification, in the
embodiment shown in FIG. 31, the burst cutting area BCA
and system lead-in area SYLDI are separated from each
other in location without being superimposed on each
other. These areas are physically separated from each
other, thereby making it possible to prevent
interference between the information recorded in the
system lead-in area SYLDI at the time of information
reproduction and the information recorded in the burst
cutting area BCA and to allocate information
reproduction with high precision.
In the case where an "L-H" type recording film has
been used as another embodiment, there is a method for
forming fine irregularities in advance in location for
allocating the burst cutting area BCA. A description
will be given later with respect to information on
polarity (identification of "H-L" or "L-H") of a
recording mark which exists at a 192nd byte in FIG. 42.
In this section, a description will be given with
respect to the present embodiment in which an "L-H"
recording film as well as the "H-L" recording film is
also incorporated in a specification and a scope of
selecting the recording film is widened to enable high
speed recording or supply of an inexpensive medium. As
described later, the present embodiment also considers
a case of using the "L-H" recording film. Data
recorded in the burst cutting area BCA (barcode data)
is formed by locally carrying out laser exposure to a
recording film. As shown in FIGS. 35A, 35B and 35C,
the system lead-in area SYLDI is formed of the emboss
bit area 211, and thus, the reproduction signal from
the system lead-in area SYLDI appears in a direction in
which a light reflection amount decreases as compared
with a light reflection level from the mirror surface
210. If while the burst cutting area BCA is formed as
the mirror surface 210, in the case where the "L-H"
recording film has been used, a reproduction signal
from the data recorded in the burst cutting area BCA
appears in a direction in which a light reflection
amount increases more significantly than a light
reflection level from the mirror surface 210 (in an
unrecorded state). As a result, a significant step
occurs between a position (amplitude level) of a
maximum level and a minimum level of the reproduction
signal from the data recorded in the burst cutting area
BCA and a position (amplitude level) of a maximum level
and a minimum level of the reproduction signal from the
system lead-in area SYLDI. As described later with
respect to FIGS. 35A, 35B and 35C, an information
reproducing apparatus or an information
recording/reproducing apparatus carry out processing in
accordance with the steps of:
1) reproducing information in the burst cutting
area BCA;
2) reproducing information contained in a
information data zone CDZ in the system lead-in area
SYLDI;
3) reproducing information contained in the data
lead-in area DTLDI (in the case of write-once type or
rewriting type);
4) readjusting (optimizing) a reproduction circuit
constant in a reference code recording zone RCZ; and
5) reproducing information recorded in the data
area DTA or recording new information.
Thus, if there exists a large step between a
reproduction signal amplitude level from the data
formed in the burst cutting area BCA and a reproduction
signal amplitude level from the system lead-in area
SYLDI, there occurs a problem that the reliability of
information reproduction is lowered. In order to solve
this problem, in the case where the "L-H" recording
film is used as a recording film, the present
embodiment is featured in that fine irregularities are
formed in advance in thus burst cutting area BCA. When
such fine irregularities are formed, the light
reflection level becomes lower than that from the
mirror surface 210 due to a light interference effect
at the stage prior to recording data (barcode data) by
local laser exposure. Then, there is attained an
advantageous effect that a step is remarkably decreased
between a reproduction signal amplitude level
(detection level) from the data formed in the burst
cutting area BCA and a reproduction signal amplitude
level (detection level) from the system lead-in area
SYLDI; the reliability of information reproduction is
improved; and processing going from the above item 1)
to item 2) is facilitated. In the case of using the
"L-H" recording film, the specific contents of fine
irregularities formed in advance in the burst cutting
area BCA include the emboss pit area 211 like the
system lead-in area SYLDI. Another embodiment includes
a method for forming the groove area 214 or the land
area and the groove area 213 like the data lead-in area
DTLDI or data area DTA. As has been described in the
description of embodiments in which the system lead-in
area SYSDI and burst cutting area BCA are separately
arranged, if the burst cutting area BCA and the emboss
bit area 211 overlaps each other, there increases a
noise component from the data provided in the burst
cutting area BCA due to unnecessary interference to a
reproduction signal. When the groove area 214 or the
land area and groove area 213 is formed without forming
the emboss pit area 211 as an embodiment of the fine
irregularities in the burst cutting area BCA, there is
attained an advantageous effect that there decreases a
noise component from the data formed in the burst
cutting area BCA due to unnecessary interference to a
reproduction signal and the quality of a reproduction
signal is improved. When track pitches of the groove
area 214 or the land area and groove area 213 formed in
the burst cutting area BCA are adjusted to conform with
the those of the system lead-in area SYLDI, there is
attained an advantageous effect that the manufacturing
performance of the information storage medium is
improved. That is, at the time of original master
manufacturing of the information storage medium, emboss
pits in the system lead-in area are produced while a
feed motor speed is made constant. At this time, the
track pitches of the groove area 214 or the land area
and groove area 213 formed in the burst cutting area
BCA are adjusted to conform with those of the emboss
pits in the system lead-in area SYLDI, thereby making
it possible to continuously maintain a constant motor
speed in the burst cutting area BCA and the system
lead-in area SYLDI. Thus, there is no need for
changing the speed of the feed motor midway, and thus,
the pitch non-uniformity hardly occurs, and the
manufacturing performance of the information storage
medium is improved.
FIG. 32 shows parameter values according to the
present embodiment in a read-only type information
storage medium; FIG. 33 shows parameter values
according to the present embodiment in a write-once
type information storage medium; and FIG. 34 shows
parameter values according to the present embodiment in
a rewritable type information storage medium. As is
evident in comparison between FIG. 32 or 33 and FIG. 34
(in particular, in comparison of section (B)), the
rewritable type information storage medium has higher
recording capacity than the read-only type or
write-once type information storage medium by narrowing
track pitches and line density (data bit length). As
described later, in the rewritable type information
storage medium, the track pitches are narrowed by
reducing effect of a cross-talk of the adjacent tracks
by employing land-groove recording. Alternatively, any
of the read-only type information storage medium,
write-once information storage medium, and rewritabletype
information storage medium is featured in that the
data bit length and track pitches (corresponding to
recording density) of the system lead-in/system leadout
areas SYLDI/SYLDO are greater than those of the
data lead-in/data lead-out area DTLDI/DTLDO (in that
the recording density is low). The data bit length and
track pitches of the system lead-in/system lead-out
areas SYLDI/SYLDO are close to the values of the
current DVD lead-in area, thereby realizing
compatibility with the current DVD. In the present
embodiment as well, like the current DVD-R, an emboss
step in the system lead-in/system lead-out areas
SYLDI/SYLDO of the write-once type information storage
medium is shallowly defined. In this manner, there is
attained advantageous effect that a depth of a pregroove
of the write-once information storage medium is
shallowly defined and a degree of modulation of a
reproduction signal from a recording mark formed on a
pre-groove by additional writing is increased. In
contrast, as a counteraction against it, there occurs a
problem that the degree of modulation of the
reproduction signal from the system lead-in/system
lead-out areas SYLDI/SYLDO decreases. In order to
solve this problem, the data bit length (and track
pitches) of system lead-in/system lead-out areas
SYLDI/SYLDO are roughened and a repetition frequency of
pits and spaces at the narrowest position is isolated
(significantly reduced) from an optical shutdown
frequency of an MTF (Modulation Transfer Function) of a
reproduction objective lens, thereby making it possible
to increase the reproduction signal amplitude from the
system lead-in/system lead-out areas SYLDI/SYLDO and to
stabilize reproduction.
FIGS. 35A, 35B and 35C show a comparison of
detailed data structure in a system lead-in area SYLDI
and a data lead-in area DTLDI in a variety of
information storage mediums. FIG. 35A shows a data
structure of a read-only type information storage
medium; FIG. 35B shows a data structure of a
rewritable-type information storage medium; and
FIG. 35C shows a data structure of a write-once type
information storage medium.
As shown in FIG. 35A, except that only a
connection zone CNZ is formed as a mirror surface 210,
the read-only type information storage medium is
featured in that the emboss pit area 211 having emboss
pits formed therein is provided in all of the system
lead-in area SYLDI and data lead-in area DTLDI and data
area DTA. The emboss pit area 211 is provided in the
system lead-in area SYLDI, and the connection zone CNZ
is provided in the mirror surface 210. As shown in
FIG. 35B, the rewritable-type information storage
medium is featured in that the land area and the groove
area 213 are formed in the data lead-in area DTLSI and
the data area DTA. The write-once type information
storage medium is featured in that the groove area 214
is formed in the data lead-in area DTLDI and the data
area DTA. Information is recorded by forming a
recording mark in the land area and the groove area 213
or groove area 214.
The initial zone INZ indicates a start position of
the system lead-in area SYLDI. As significant
information recorded in the initial zone INZ, there is
discretely arranged data ID (Identification Data)
information including information on physical sector
numbers or logical sector numbers described previously.
As described later, one physical sector records
information on a data frame structure composed of data
ID, IED (ID Error Detection code), main data for
recording user information, and EDC (Error detection
code); and the initial zone records information on the
above described data frame structure. However, in the
initial zone INZ, all the information on the main data
for recording the user information is all set to "OOh",
and thus, the significant information contained in the
initial zone INZ is only data ID information. A
current location can be recognized from the information
on physical sector numbers or logical sector numbers
recorded therein. That is, when an information
recording/reproducing unit 141 shown in FIG. 11 starts
information reproduction from an information storage
medium, in the case where reproduction has been started
from the information contained in the initial zone INZ,
first, the information on physical sector numbers or
logical sector numbers recorded in the data ID
information is sampled, and the sampled information is
moved to the control data, zone CDZ while the current
location in the information storage medium is checked.
A buffer zone 1 BFZl and a buffer zone 2 BFZ2 each
are composed of 32 ECC blocks. As shown in FIGS. 32,
33 and 34, one ECC block corresponds to 1024 physical
sectors. In the buffer zone I BFZl and the buffer zone
2 BFZ2 as well, like the initial zone INZ, main data
information is set to all "OOh".
The connection zone CNZ which exists in a CNA
(Connection Area) is an area for physically separating
the system lead-in area SYLDI and the data lead-in area
DTLDI from each other. This area is provided as a
mirror surface on which no emboss pit or pre-groove
exists.
An RCZ (Reference code zone) of the read-only type
information storage medium and the write-once type
information storage medium each is an area used for
reproduction circuit tuning of a reproducing apparatus
(for automatic adjustment of tap coefficient values at
the time of adaptive equalization carried out in the
tap controller 332 shown in FIG. 15) , wherein
information on the data frame structure described
previously is recorded. A length of the reference code
is one ECC block (= 32 sectors). The present
embodiment is featured in that the RCZ (Reference code
zone) of the read-only type information storage medium
and the write-once information storage medium each is
arranged adjacent to a DTA (data area). In any of the
structures of the current DVD-ROM disk and the current
DVD-R disk as well, a control data zone is arranged
between the reference code zone and data area, and the
reference code zone and the data area are separated
from each other. If the reference code zone and data
area are separated from each other, a tilt amount or a
light reflection factor of the information storage
medium or the recording sensitivity of a recording film
(in the case of the write-once information storage
medium) slightly changes. Therefore, there occurs a
problem that an optimal circuit constant in the data
area is distorted even if a circuit constant of the
reproducing apparatus is adjusted. In order to solve
the above described problem, when the RCZ (reference
code zone) is arranged adjacent to the DTA (data area),
in the case where the circuit constant of the
information reproducing apparatus has been optimized in
the RCZ (reference code zone), an optimized state is
maintained by the same circuit constant in the DTA
(data area). In the case where an attempt is made to
precisely reproduce a signal in arbitrary location in
the DTA (data area), it becomes possible to reproduce a
signal at a target position very precisely in
accordance with the steps of:
1) optimizing a circuit constant of the
information reproducing apparatus in the RCZ (reference
code zone);
2) optimizing a circuit constant of the
information reproducing apparatus again while
reproducing a portion which is the closest to the
reference code zone RCZ in the data area DTA;
3) optimizing a circuit constant once again while
reproducing information at an intermediate position
between a target position in the data area DTA and the
position optimized in step 2); and
4) reproducing signal after moving to the target
position.
GTZ1 and GTZ2 (guard track zones 1 and 2) existing
in the write-once information storage medium and the
rewritable-type information storage medium are areas
for specifying the start boundary position of the data
lead-in area DTLDI, and a boundary position of a drive
test zone DRTZ and a disc test zone DKTZ. These areas
are prohibited from being recorded a recording mark.
The guard track zone 1 GTZ1 and guard track zone 2 GTZ2
exist in the data lead-in area DTLDI, and thus, in this
area, the write-once type information storage medium is
featured in that the pre-groove area is formed in
advance. Alternatively, the rewritable-type
information storage medium is featured in that the
groove area and the land area are formed in advance.
In the pre-groove area or groove area and the land
area, as shown in FIGS. 32, 33 and 34, wobble addresses
are recorded in advance, and thus, the current location
in the information storage medium is determined by
using these wobble addresses.
The disk test zone DKTZ is an area provided for
manufactures of information storage mediums to carry
out quality test (evaluation).
The drive test zone DRTZ is provided as an area
for carrying out test writing before the information
recording/reproducing apparatus records information in
the information storage medium. The information
recording/reproducing apparatus carries out test
writing in advance in this area, and identifies an
optimal recording condition (write strategy). Then,
the information contained in the data area DTA can be
recorded under the optimal recording condition.
The information recorded in the disk
identification zone DIZ which exists in the rewritabletype
information storage medium (FIG. 35B) is an
optional information recording area, the area being
adopted to additionally write a set of drive
descriptions composed of: information on manufacturer
name of recording/reproducing apparatuses; additional
information relating thereto; and an area in which
recording can be uniquely carried out by the
manufacturers.
A defect management area 1 DMA1 and a defect
management area 2 DMA2 which exist in a rewritable-type
information storage medium (FIG. 35B) record defect
management information contained in the data area DTA,
and, for example, substitute site information when a
defect occurs or the like is recorded.
In the write-once type information storage medium
(FIG. 35C), there exist uniquely: an RMD duplication
zone RDZ; a recording management zone RMZ; and an R
physical information zone R-PFIZ. The recording
management zone RMZ records RMD (recording management
data) which is an item of management information
relating to a recording position of data updated by
additional writing of data. A detailed description will
be given later. As described later in FIGS. 36 (a),
(b), (c) and (d), in the present embodiment, a
recording management zone RMZ is set for each bordered
area BRDA, enabling area expansion of the recording
management zone RMZ. As a result, even if the required
recording management data RMD increases due to an
increase of additional writing frequency, such an
increase can be handled by expanding the recording
management zone RMZ in series, and thus, there is
attained advantageous effect that the additional
writing count can be significantly increased. In this
case, in the present embodiment, the recording
management zone RMZ is arranged in a border-in BRDI
which corresponds to each bordered area BRDA (arranged
immediately before each bordered area BRDA). In the
present embodiment, the border-in BRDI corresponding to
the first bordered area BRDA#1 and a data lead-in area
DTLDI are made compatible with each other, and
efficient use of the data area DTA is promoted while
the forming of the first border-in BRDI in the data
area DTA is eliminated. That is, the recording
management zone RMZ in the data lead-in area DTA shown
in FIG. 35C is utilized as a recording location of the
recording management data RDM which corresponds to the
first bordered area BRDA#1.
The RMD duplication zone RDZ is a location for
recording information on the recording management data
RMD which meets the following condition in the
recording management zone RMZ, and the reliability of
the recording management data RMD is improved by
providing the recording management data RMD in a
duplicate manner, as in the present embodiment. That
is, in the case where the recording management data RMD
contained in the recording management zone RMZ is valid
due to dust or scratch adhering to a write-once
information storage medium surface, the recording
management data RMD is reproduced, the data being
recorded in this RMD duplication zone RDZ. Further,
the remaining required information is acquired by
tracing, whereby information on the latest recording
management data RMD can be restored.
This RMD duplication zone records recording
management data RDM at a time point at which (a
plurality of) borders are closed. As described later,
a new recording management zone RMZ is defined every
time one border is closed and a next new bordered area
is set. Thus, every time a new recording management
zone RMZ is created, the last recording management data
RMD relating to the preceding bordered area may be
recorded in this RMD duplication zone RDZ. When the
same information is recorded in this RMD duplication
zone RDZ every time the recording management data RDM
is additionally recorded on a write-once information
storage medium, the RMD duplication zone RDZ becomes
full with a comparatively small additional recording
count, and thus, an upper limit value of the additional
writing count becomes small. In contrast, as in the
present embodiment, in the case where a recording
management zone is newly produced when a border is
closed, the recording management zone in the border-in
BRDI becomes full, and a new recording management zone
RMZ is formed by using an R zone, there is attained
advantageous effect that only the last recording
management data RMD contained in the past recording
management zone RMZ is recorded in the RMD duplication
zone RDZ, thereby making it possible to improve an
allowable additional writing count by efficiently using
the RMD duplication zone RDZ.
For example, in the case where the recording
management data RMD contained in the recording
management zone RMZ which corresponds to the bordered
area BRDA on the way of additional writing (before
closed) cannot be reproduced due to the dust or scratch
adhering to the surface of the write-once type
information storage medium, a location of the bordered
area BRDA, which has been already closed, can be
identified by reading the recording management data RMD
lastly recorded in this RMD duplication zone RDZ.
Therefore, the location of the bordered area BRDA on
the way of additional writing (before closed) and the
contents of information recorded therein can be
acquired by tracing another location in the data area
DTA of the information storage medium, and the
information on the latest recording management data RMD
can be restored.
An R physical information zone R-PFIZ records the
information analogous to the physical format PFI
contained in the control data zone CDZ which exists
common to FIGS. 35A to 35C (described later in detail).
FIG. 36 shows a data structure in the RMD
duplication zone RDZ and the recording management zone
RMZ which exists in the write-once type information
storage medium (FIG. 35C). FIG. 36 (a) shows the same
structure as that shown in FIG. 35C, and FIG. 36 (b)
shows an enlarged view of the RMD duplication zone RDZ
and the recording management zone RDZ shown in
FIG. 35C. As described above, in the recording
management zone RMZ contained in the data lead-in area
DTLDI, data relating to recording management which
corresponds to the first bordered area BRDA is
collectively recorded, respectively, in one items of
recording management data (RMD); and new recording
management data RMD is sequentially additionally
written at the back side every time the contents of the
recording management data RMD generated when additional
writing process has been carried out in the write-once
information storage medium are updated. That is, the
RMD (Recording Management Data) is recorded in size
units of single physical segment block (a physical
segment block will be described later), and new
recording management data RMD is sequentially
additionally written every time the contents of data
are updated. In the example shown in FIG. 36 (b), a
change has occurred with management data in location
recording management data RMD#1 and RMD#2 has been
recorded. Thus, this figure shows an example in which
the data after changed (after updated) has been
recorded as recording management data RMD#3 immediately
after the recording management data RMD#2. Therefore,
in the recording management zone RMD, a reserved area
273 exists so that additional writing can be further
carried out.
Although FIG. 36 (b) shows a structure in the
recording management zone RMZ which exists in the data
lead-in area DTLDI, a structure in the recording
management zone RMZ (or expanded recording management
zone: referred to as expanded RMZ) which exists in the
border-in BRDI or bordered area BRDA described later is
also identical to the structure shown in FIG. 36 (b)
without being limited thereto.
In the present embodiment, in the case where a
first bordered area BRDA#1 is closed or in the case
where the terminating process (finalizing) of the data
area DTA is carried out, a processing operation for
padding all the reserved area 273 shown in FIG. 36 (b)
with the latest recording management data RMD
duplication zone is carried out. In this manner, the
following advantageous effects are attained:
1) An "unrecorded" reserved area 273 is
eliminated, and the stabilization of tracking
correction due to a DPD (Differential Phase Detection)
technique is guaranteed;
2) the latest recording management data RMD is
overwritten in the past reserved area 273, thereby
remarkably improving the reliability at the time of
reproduction relating to the last recording management
data RMD; and
3) an event that different items of recording
management data RMD are mistakenly recorded in an
unrecorded reserved area 273 can be prevented.
The above processing method is not limited to the
recording management zone RMZ contained in the data
lead-in area DTLDI. In the present embodiment, with
respect to the recording management zone RMZ (or
expanded recording management zone: referred to as
expanded RMZ) which exists in the border-in BRDI or
bordered area BRDA described later, in the case where
the corresponding bordered area BRDA is closed or in
the case where the terminating process (finalizing) of
the data area DTA is carried out, a processing
operation for padding all the reserved area 273 shown
in FIG. 36 (b) with the latest recording management
data RMD is carried out.
The RMD duplication zone RDZ is divided into the
RDZ lead-in area RDZLI and a recording area 271 of the
last recording management data RMD duplication zone RDZ
of the corresponding RMZ. The RDZ lead-in area RDZLI
is composed of a system reserved field SRSF whose data
size is 48 KB and a unique ID field UIDF whose data
size is 16 KB, as shown in FIG. 36 (b). All "OOh" are
set in the system reserved field SRSF.
The present embodiment is featured in that DRZ
lead-in area RDZLI is recorded in the data lead-in area
DTLDI which can be additionally written. In the writeonce
type information storage medium according to the
present embodiment, the medium is shipped with the RDZ
lead-in area RDZLI being in an unrecorded state
immediately after manufacturing. In the user's
information recording/reproducing apparatus, at a stage
of using this write-once type information storage
medium, RDZ lead-in area RDZLI information is recorded.
Therefore, it is determined whether or not information
is recorded in this RDZ lead-in area RDZLI immediately
after the write-once type information storage medium
has been mounted on the information
recording/reproducing apparatus, thereby making it
possible to easily know whether or not the target
write-once type information storage medium is in a
state immediately after manufacturing/shipment or has
been used at least once. Further, as shown in FIG. 36,
the present embodiment is secondarily featured in that
the RMD duplication zone RDZ is provided at the inner
periphery side than the recording management zone RMZ
which corresponds to a first bordered area BRDA, and
the RDZ lead-in RDZLI is arranged in the RMD
duplication zone RDZ.
The use efficiency of information acquisition is
improved by arranging information (RDZ lead-in area
RDZLI) representing whether or not the write-once type
information storage medium is in a state immediately
after manufacturing/shipment or has been used at least
once in the RMD duplication zone RDZ used for the
purpose of a common use (improvement of reliability of
RMD). In addition, the RDZ lead-in area RDZLI is
arranged at the inner periphery side than the recording
management zone RMZ, thereby making it possible to
reduce a time required for acquisition of required
information. When the information storage medium is
mounted on the information recording/reproducing
apparatus, the information recording/reproducing
apparatus starts reproduction from the burst cutting
area BCA arranged at the innermost periphery side, as
described in FIG. 31, and sequentially changes a
reproducing location from the system lead-in SYLSI to
the data lead-in area DTLDI while the reproduction
position is sequentially moved to the innermost
periphery side. It is determined whether or not
information has been recorded in the RDZ lead-in area
RDZLI contained in the RMD duplication zone RDZ. In a
write-once type information storage medium in which no
recording is carried out immediately after shipment, no
recording management data RMD is recorded in the
recording management zone RMZ. Thus, in the case where
no information is recorded in the RDZ lead-in area
RDZLI, it is determined that the medium is "unused
immediately after shipment", and the reproduction of
the recording management zone RMD can be eliminated,
and a time required for acquisition of required
information can be reduced.
As shown in FIG. 36 (c), a unique ID area UIDF
records information relating to an information
recording/reproducing apparatus for which the writeonce
type information storage medium immediately after
shipment has been first used (i.e., for which recording
has been first started). That is, this area records a
drive manufacturer ID 281 of the information
recording/reproducing apparatus or serial number 283
and model number 284 of the information
recording/reproducing apparatus. The unique ID area
UIDF repeatedly records the same information for 2 KB
(strictly, 2048 bytes) shown in FIG. 36 (c).
Information contained in the unique disk ID 287 records
year information 293, month information 294, date
information 295, time information 296, minutes
information 297, and seconds information 298 when the
storage medium has been first used (recording has been
first started). A data type of respective items of
information is described in HEX, BIN, ASCII as
described in FIG. 36 (d), and two types or four bytes
are used.
The present embodiment is featured in that the
size of an area of this RDZ lead-in area RDZLI and the
size of the one recording management data RMD are 64
KB, i.e., the user data size in one ECC block becomes
an integer multiple. In the case of the write-once
type information storage medium, it is impossible to
carry out a processing operation for rewriting ECC
block data after changed in the information storage
medium after changing part of the data contained in one
ECC block. Therefore, in particular, in the case of
the write-once type information storage medium, as
described later, data is recorded in recording cluster
units composed of an integer multiple of a data segment
including one ECC block. Therefore, the size of the
area of the RDZ lead-in area RDZLI and the size of such
one item of recording management data RMD are different
from a user data size in an ECC block, there is a need
for a padding area or a stuffing area for making
adjustment to the recording cluster unit, and a
substantial recording efficiency is lowered. As in the
present embodiment, the size of the area of the RDZ
lead-in area RDZLI and the size of such one item of
recording management data RMD are set to an integer
multiple of 64 KB, thereby making it possible to lower
the recording efficiency.
A description will be given with respect to a last
recording management data RMD recording area 271 of the
corresponding RMZ shown in FIG. 36 (b). As described
in Japanese Patent No. 2621459, there is a method for
recording intermediate information at the time of
interruption of recording inwardly of the lead-in area.
In this case, every time recording is interrupted or
every time an additional writing process is carried
out, it is necessary to serially additionally write
intermediate information in this area (recording
management data RMD in the present embodiment). Thus,
if such recording interruption or additional writing
process is frequently repeated, there is a problem that
this area becomes full immediately and a further adding
process cannot be carried out. In order to solve this
problem, the present embodiment is featured in that an
RMD duplication zone RDZ is set as an area capable of
recording the recording management data RMD updated
only when a specific condition is met and the recording
management data RMD sampled under such a specific
condition is recorded. Thus, there is attained
advantageous effect that the RMD duplication zone RDZ
can be prevented from being full and the numbers of
additional writings enable with respect to the writeonce
type information storage medium can be remarkably
improved by lowering the frequency of the recording
management data RMD additionally written in the RMD
duplication zone RDZ. In parallel to this effect, the
recording management data updated every time an
additional writing process is carried out is serially
additionally written in the recording management zone
RMZ in the border-in area BRDI shown in FIG. 36 (a) (in
the data lead-in area DTLDI as shown in FIG. 36 (a)
with respect to the first bordered area BRDA#1) or the
recording management zone RMZ utilizing an R zone
described later. When a new recording management zone
RMZ is created, for example, when the next bordered
area BRDA is created (new border-in area BRDI is set)
or when a new recording management zone RMZ is set in
an R zone, the last recording management data RMD (the
newest RMD in a state immediately before creating a new
recording management zone RMZ) is recorded in (the
corresponding last recording management data RMD
recording area 271) contained in the RMD duplication
zone RDZ. In this manner, there is attained
advantageous effect that a newest RMD position search
is facilitated by utilizing this area in addition to a
significantly increase of additional writing enable
count for the write-once type information storage
medium.
FIG. 38 shows a data structure in the recording
management data RMD shown in FIG. 36. FIG. 38 shows
the same contents of FIG. 36. As described previously,
in the present embodiment, the border-in area BRDI for
the first bordered area BRDA#1 is partially compatible
with the data lead-in area DTLDI, and thus, the
recording management data RMD#1 to #3 corresponding to
the first bordered area are recorded in the recording
management zone RMZ in the data lead-in area DTLDI. In
the case where no data is recorded in the data area
DTA, the inside recording management zone RMZ is
provided as a reserved area 273 in which all data is in
an unrecorded state. The recording management data RMD
updated every time data is additionally written in the
data area DTA is recorded in first location contained
in this reserved area 273, and the corresponding
recording management data RMD is sequentially
additionally written in the first bordered area
contained in the recording management zone RMZ. The
size of the recording management data RMD additionally
written each time in the recording management zone RMZ
is defined as 64 KB. In the present embodiment, one
ECC block is composed of 64 KB data, and thus, an
additional writing process is simplified by adjusting
the data size of this recording management data RMD to
conform with one ECC block size. As described later,
in the present embodiment, one data segment 490 is
configured by adding part of a guard area before and
after one ECC block data 412, and recording clusters
540 and 542 in units of additional writing or rewriting
are configured by adding expanded guard fields 258 and
259 to one or more (n) data segments. In the case of
recording the recording management data RMD, the
recording clusters 540 and 542 including only one data
segment (one ECC block) are sequentially additionally
written in this recording management zone RMZ. As
described later, a length of a location for recording
one data segment 531 corresponds to that of one
physical segment block composed of seven physical
segments 550 to 556.
FIG. 38 (c) shows a data structure in one
recording management data RMF#1. FIG. 38 (c) shows a
data structure in recording management data RMD#1
contained in the data lead-in area DTLDI. The
illustrated data structure is identical to a data
structure in the recording management data RMD#A and #B
(FIG. 36 (b)) recorded in the RMD duplication zone RDZ;
(expanded) recording management data RMD recorded in a
border-in area BRDI described later; (expanded)
recording management data RMD recorded in an R zone;
and copy CRMD of RMD recorded in the border-out area
BRDO (FIG. 39 (d)) as well. As shown in FIG. 38 (c) ,
one item of recording management data RMD is composed
of a reserved area and RMD fields ranging from "0" to
"21". In the present embodiment, 32 physical sectors
are included in one ECC block composed of 64 KB user
data, and user data of 2 KB (strictly, 2048 bytes) is
recorded in one physical sector. Each RMD field are
assigned by 2048 bytes in conformance to a user data
size recorded in this physical sector, and relative
physical sector numbers are set. RMD fields are
recorded on a write-once type information storage
medium in order of these relative physical sector
numbers. The contents of data recorded in each RMD
field are as follows:
RMD field 0 ... Information relating to disk state
and data area allocation (information relating to
location for allocating a variety of data in data area)
RMD field 1 ... Information relating to used test
zone and information relating to recommended recording
waveform
RMD field 2 ... User available area
RMD field 3 ... Start position information on
border area and information relating to expanded RMZ
position
RMD fields 4 to 21 ... Information relating to
position of R zone
As shown in FIG. 35 in any of the read-only type,
write-once type, and rewritable-type information
storage medium, the present embodiment is featured in
that a system lead-in area is arranged at an opposite
side of a data area while a data lead-in area is
sandwiched between the two areas, and further, as shown
in FIG. 31, the burst cutting area BCA and the data
lead-in area DTLDI are arranged at an opposite side to
each other while the system lead-in area SYSDI is
sandwiched between the two areas. When an information
storage medium is inserted into the information
reproducing apparatus or information
recording/reproducing apparatus shown in FIG. 11, the
information reproducing apparatus or information
recording/reproducing apparatus carries out processing
in accordance with the steps of:
1) reproducing information contained in the burst
cutting area BCA;
2) reproducing information contained in the
information data zone CDZ contained in the system leadin
area SYLDI;
3) reproducing information contained in the data
lead-in area DTLDI (in the case of a write-once type or
a rewritable-type medium);
4) readjusting (optimizing) a reproduction circuit
constant in the reference code zone RCZ; and
5) reproducing information recorded in the data
area DTA or recording new information.
As shown in FIG. 35, information is sequentially
arranged from the inner periphery side along the above
processing steps, and thus, a process for providing an
access to an unnecessary inner periphery is eliminated,
the number of accesses is reduced, and the data area
DTA can be accessed. Thus, there is attained
advantageous effect that a start time for reproducing
the information recording in the data area or recording
new information is accelerated. In addition, RPML is
used for signal reproduction in the data lead-in area
DTDLI and data area DTA by utilizing a slice level
detecting system for signal reproduction in the system
lead-in area SYLDI. Thus, if the data lead-in area
DTLDI and the data area DTA are made adjacent to each
other, in the case where reproduction is carried out
sequentially from the inner periphery side, a signal
can be stably reproduced continuously merely by
switching a slice level detecting circuit to a PRML
detector circuit only once between the system lead-in
area SYLDI and the data lead-in area DTLDI. Thus, the
number of reproduction circuit switchings along the
reproduction procedures is small, thus simplifying
processing control and accelerating a data intra-area
reproduction start time.
FIG. 37 shows a comparison of the data structures
in the data areas DTA and the data lead-out areas DTLDO
in a variety of information storage mediums.
FIG. 37 (a) shows a data structure of a read-only type
information storage medium; FIGS. 37(b) and 37(c) each
show a data structure of a writing-type information
storage medium; and FIG. 37(d) to 37(f) each show a
data structure of a write-once type information storage
medium. In particular, FIGS. 37 (b) and 37(d) each show
a data structure at the time of an initial state
(before recording); and FIGS. 37(c), 37 (e) and 37 (f)
each show a data structure in a state in which
recording (additional writing or rewriting) has
advanced to a certain extent.
As shown in FIG. 37 (a), in the read-only type
information storage medium, the data recorded in the
data lead-out area DTLDO and the system lead-out area
SYLDO each have a data frame structure (described later
in detail) in the same manner as in the buffer zone 1
BFZ1 and buffer zone 2 BFZ2 shown in FIGS. 35 (a) to
35 (c), and all values of the main data contained
therein are set to "OOh". In the read-only type
information storage medium, a user data prerecording
area 201 can be fully used in the data area DTA.
However, as described later, in any of the embodiments
of the write-once information storage medium and
rewritable-type information storage medium as well,
user rewriting/additional writing enable ranges 202 to
205 are narrower than the data area DTA.
In the write-once information storage medium or
rewritable-type information storage medium, an SPA
(Spare Area) is provided at the innermost periphery of
the data area DTA. In the case where a defect has
occurred in the data area DTA, a substituting process
is carried out by using the spare area SPA. In the
case of the rewritable-type information storage medium,
the substitution history information (defect management
information) is recorded in a defect management area 1
(DMAl) and a defect management area 2 (DMA2) shown in
FIG. 35(b); and a detect management area 3 (DMA3) and a
defect management area 4 (DMA4) shown in FIGS. 37(b)
and 37 (c) . The defect management information recorded
in the defect management area 3 (DMAS) and defect
management area 4 (DMA4) shown in FIGS. 37(b) and 37(c)
are recorded as the same contents of the defect
management information recorded in the defect
management information 1 (DMAl) and defect management
information 2 (DMA2) shown in FIG. 35B. In the case of
the write-once type information storage medium,
substitution history information (defect management
information) in the case where the substituting process
has been carried out is recorded in the data lead-in
area DTLDI shown in FIG. 35C and copy information C_RMZ
on the contents of receding in a recording management
zone which exists in a border zone. Although defect
management has not been carried out in a current DVD-R
disk, DVD-R disks partially having a defect location
are commercially available as the manufacture number of
DVD-R disks increases, and there is a growing need for
improving the reliability of information recorded in a
write-once type information storage medium. In the
embodiment shown in FIGS. 37A to 37F, a spare area SPA
is set with respect to the write-once information
storage medium, enabling defect management by a
substituting process. In this manner, a defect
management process is carried out with respect to the
write-once type information storage medium partially
having a defect location, thereby making it possible to
improve the reliability of information. In the
rewritable-type information storage medium or writeonce
type information storage medium, in the case where
a defect frequently has occurred, a user judges an
information recording/reproducing apparatus, and an
ESPA, ESPA1, and ESPA2 (Expanded Spare Areas) are
automatically set with respect to a state immediately
after selling to the user shown in FIGS. 37A and 37D so
as to widen a substitute location. In this manner, the
expanded spare areas ESPA, ESPA1, and ESPA2 can be set,
thereby making it possible to sell mediums with which a
plenty of defects occur for a manufacturing reason. As
a result, the manufacture yield of mediums is improved,
making it possible to reduce a medial price. As shown
in FIGS. 37A, 37E and 37F, when the expanded spare
areas ESPA, ESPA1, and ESPA2 are expanded in the data
area DTA, user data rewriting or additional writing
enable ranges 203 and 205 decrease(s), thus making it
necessary to management its associated positional
information. In the rewritable-type information
storage medium, the information is recorded in the
defect management area 1 (DMA1) to the defect
management area 4 (DMA4) and in the control data zone
CDZ, as described later. In the case of the write-once
type information storage medium, as described later,
the information is recorded in recording management
zones RMZ which exist in the data lead-in area DTLDI
and in the border-out BRDO. As described later, the
information is recorded in the RMD (Recording
Management Data) contained in the recording management
zone RMZ. The recording management data RMD is updated
or additionally written in the receding management zone
RMZ every time the contents of management data are
updated. Thus, even if an expanded spare area is reset
many times, timely updating and management can be
carried out. (The embodiment shown in FIG. 37E
indicates a state in which an expanded spare area 2
(ESPA2) has been set because further area substituting
setting is required due to a number of defects even
after the expanded spare area 1 (ESPA1) has been fully
used).
A guard track zone 3 (GTZ3) shown in FIGS. 37B and
37C each is arranged to separate a defect management
area 4 (DMA4) and a drive test zone (DRTS) from each
other, and a guard track zone 4 (GTZ4) is arranged to
separate a disk test zone DKTZ and a servo calibration
zone SCZ from each other. The guard track zone 3
(GTZ3) and guard track zone 4 (GTZ4) are specified as
area which inhibits recording by forming a recording
mark, as in the guard track zone 1 (GTZl) and guard
track zone 2 (GTZ2) shown in FIGS. 35A to 35C. The
guard track zone 3 (GTZ3) and the guard track zone 4
(GTZ4) exist in the data lead-out area DTLDO. Thus, in
these areas, in the write-once type information storage
medium, a pre-groove area is formed in advance, or
alternatively, in the rewritable-type information
storage medium, a groove area and a land area are
formed in advance. As shown in FIGS. 32 to 34, wobble
addresses are recorded in advance in the pre-groove
area or the groove area and land area, thus judging a
current position in the information storage medium by
using this wobble addresses.
As in FIGS. 35A to 35C, a drive test zone DRTZ is
arranged as an area for test writing before an
information recording/reproducing apparatus records
information in an information storage medium. The
information recording/reproducing apparatus carries out
test writing in advance in this area, and identifies an
optimal recording condition (write strategy). Then,
this apparatus can record information in the data area
DTA under the optimal recording condition.
As shown in FIGS. 35A to 35C, the disk test zone

DKTZ is an area provided for manufacturers of
information storage mediums to carry out quality test
(evaluation).
In all of the areas contained in the data lead-out
area DTLDO other than the SCZ (Servo Calibration Zone),
a pre-groove area is formed in advance in the writeonce
type information storage medium, or alternatively,
a groove area and a land area are formed in advance in
the rewritable-type information storage medium,
enabling recording (additional writing or rewriting) of
a recording mark. As shown in FIGS. 37C and 37E, the
SCZ (Servo Calibration Zone) serves as an emboss pit
area 211 in the same manner as in the system lead-in
area SYLDI instead of the pre-groove area 214 or the
land area and groove area 213. This area forms
continuous tracks with emboss pits, which follows
another area of the data lead-out area DTLDO. These
tracks continuously communicate with each other in a
spiral manner, and form emboss pits over 360 degrees
along the circumference of the information storage
medium. This area is provided to detect a tilt amount
of the information storage medium by using a DPD
(Deferential Phase Detect) technique. If the
information storage medium tilts, an offset occurs with
a track shift detection signal amplitude using the DPD
technique, making it possible to precisely the tilt
amount from the offset amount and a tilting direction
in an offset direction. By utilizing this principle,
emboss pits capable of DPD detection are formed in
advance at the outermost periphery (at the outer
periphery in the data lead-out area DTLDO), thereby
making it possible to carry out detection with
inexpensiveness and high precision without adding
special parts (for tilt detection) to an optical head
which exists in the information recording/reproducing
unit 141 shown in FIG. 11. Further, by detecting the
tilt amount of the outer periphery, servo stabilization
(due to tilt amount correction) can be achieved even in
the data area. In the present embodiment, the track
pitches in this servo calibration zone SCZ are adjusted
to conform with another area contained in the data
lead-out area DTLD, and the manufacturing performance
of the information storage medium is improved, making
it possible to reduce a media price due to the
improvement of yields. That is, although a pre-groove
is formed in another area contained in the data leadout
area DTLDO in the write-once type information
storage medium, a pre-groove is created while a feed
motor speed of an exposure section of an original
master recording device is made constant at the time of
original master manufacturing of the write-once type
information storage medium. At this time, the track
pitches in the servo calibration zone SCZ are adjusted
to conform with another area contained in the data
lead-out area DTLDO, thereby making it possible to
continuously maintain a motor speed constantly in the
servo calibration zone SCZ as well. Thus, the pitch
non-uniformity hardly occurs, and the manufacturing
performance of the information storage medium is
improved.
Another embodiment includes a method for adjusting
at least either of the track pitches and data bit
length in the servo calibration zone SCZ to conform
with the track pitches or data bit length of the system
lead-in area SYLDI. As described previously, the tilt
amount in the servo calibration zone SCZ and its tilt
direction are measured by using the DPD technique, and
the measurement result is utilized in the data area DTA
as well, thereby promoting servo stabilization in the
data area DTA. A method for predicting a tilt amount
in the data area DTA is featured in that the tilt
amount in the system lead-in area SYLDI and its
direction are measured in advance by using the DPD
technique similarly, and a relationship with the
measurement result in the servo calibration zone SCZ is
utilized, thereby making it possible to predict the
tilt amount. In the case of using the DPD technique,
the present embodiment is featured in that the offset
amount of the detection signal amplitude relevant to a
tilt of the information storage medium and a direction
in which an offset occurs, change depending on the
track pitches and data bit length of emboss pits.
Therefore, there is attained advantageous effect that
at least either of the track pitches and data bit
length in the servo calibration zone SCZ is adjusted to
conform with the track pitches or data bit length of
the system lead-in area SYLDI, whereby the detection
characteristics relating to the offset amount of the
detection signal amplitude and the direction in which
an offset occurs are made coincident with each other
depending on the servo calibration zone SCZ and the
system lead-in area SYLDI; a correlation between these
characteristics is easily obtained, and the tilt amount
and direction in the data area DTA is easily predicted.
As shown in FIGS. 35C and 37D, in the write-once
type information storage medium, two drive test zones
DRTZ are provided at the inner periphery side and the
outer periphery side of the medium. As more test
writing operations are carried out for the drive text
zones DRTZ, parameters are finely assigned, thereby
making it possible to search an optimal recording
condition in detail and to improve the precision of
recording in the data area DTA. The rewritable-type
information storage medium enables reuse in the drive
test zone DRTZ due to overwriting. However, if an
attempt is made to enhance the recording precision by
increasing the number of test writings in the writeonce
type information storage medium, there occurs a
problem that the drive test zone is used up
immediately. In order to solve this problem, the
present embodiment is featured in that an EDRTZ
(Expanded Drive Test Zone) can be set from the outer
periphery to the inner periphery direction, making it
possible to expand a drive test zone. In the present
embodiment, features relating to a method for setting
an expanded drive test zone and a method for carrying
out test writing in the set expanded drive test zone
are described below.
1) The setting (framing) of expanded drive test
zones EDRTZ are sequentially provided collectively from
the outer periphery direction (close to the data leadout
area DTLDO) to the inner periphery side.
- As shown in FIG. 37E, the expanded drive test
zone 1 (EDRTZ1) is set as an area collected from a
location which is the closest to the outer periphery in
the data area (which is the closest to the data leadout
area DTLDO); and the expanded drive test zone 1
(EDRTZ1) is used up, thereby making it possible to
secondarily set the expanded drive test zone 2 (EDRTZ2)
as a corrected area which exists in the inner periphery
side than the current position.
2) Test writing is sequentially carried out from
the inner periphery side in the expanded dive test zone
DDRTZ.
- In the case where test writing is carried out in
the expanded drive test zone EDRTZ, such test writing
is carried out along a groove area 214 arranged in a
spiral shape from the inner periphery side to the outer
periphery side, and current test writing is carried out
for an unrecorded location that immediately follows the
previously test-written (recorded) location.
The data area is structured to be additionally
written along the groove area 214 arranged in a spiral
manner from the inner periphery side to the outer
periphery side. A processing operation from "checking
immediately test-written location" to "carrying out
current test writing" can be serially carried out by
using a method for sequentially carrying out additional
writing a location that follows a test writing location
in which test writing in the expanded drive test zone
has been carried out immediately before, thus
facilitating a test writing process and simplifying
management of the test-written location in the expanded
drive test zone EDRTZ.
3) The data lead-out area DTLDO can be reset in
the form including the expanded drive test zone.
FIG. 37E shows an example of setting two areas,
i.e., an expanded spare area 1 (ESPAl) and an expanded
spare area 2 (ESPA2) in the data area DTA and setting
two areas, i.e., the expanded drive test zone 1
(EDRTZ1) and expanded drive test zone 2 (EDRTZ2). In
this case, as shown in FIG. 37F, the present embodiment
is featured in that the data lead-out area DTLO can be
reset with respect to an area including up to the
expanded drive test zone 2 (EDRTZ2). Concurrently, the
range of data area DTA is reset in a range-narrowed
manner, making it easy to manage an additional writing
enable range 205 of the user data which exists in the
data area DTA. In the case where the resetting has
been provided as shown in FIG. 37F, a setting location
of the expanded spare area 1 (ESPAl) shown in FIG. 37E
is regarded as an "expanded spare area which has
already been used up", and an unrecorded area (area
enabling additional test writing) is managed only in
the expanded spare area 2 (ESPA2) contained in the
expanded drive test zone EDRTZ if any. In this case,
non-defect information which is recorded in the
expanded spare area 1 (ESPAl) and which has been used
up for substitution is transferred to a location of an
area which is not substituted in the expanded spare
area 2 (ESPTA2), and defect management information is
rewritten. The start position information on the reset
data lead-out area DTLDO is recorded in allocation
position information on the latest (updated) data area
DTA of RMD field 0 contained in the recording
management data RMD, as shown in FIG. 44.
A structure of a border area in a write-once type
information storage medium will be described here with
reference to FIG. 40. When one border area has been
first set in the write-once information storage medium,
an bordered area (Bordered Area) BRDA#1 is set at the
inner periphery size (which is the closest to the data
lead-in area DTLDI), as shown in FIG. 40 (a), and then,
a border out (Border out) BRDO that follows the above
area is formed.
Further, in the case where an attempt is made to
set a next bordered area (Bordered Area) BRDA2, as
shown in FIG. 40 (b), a next (1) border in area BRDI
that follows the preceding 1 border out area BRDO is
formed, and then, a next bordered area BRDA2 is set.
In the case where an attempt is made to close the next
bordered area BRDA2, a (2) border out area BRDO that
immediately follows the area BRDA2 is formed. In the
present embodiment, a state in which the next ((1)
border in area BRDI) that follows the preceding (1)
border out area BRDO is formed and combined is referred
to as a border zone BRDZ. The border zone BRDZ is set
to prevent an optical head from overrun between the
bordered areas BRDAs when reproduction has been carried
out by using the information reproducing apparatus (on
the presumption that the DPD detecting technique is
used). Therefore, in the case where a write-once type
information storage medium having information recorded
therein is reproduced by using a read-only apparatus,
it is presumed that a border close process is made such
that the border out area BRDO and border-in area BRDI
are already recorded and the border out area BRDO that
follows the last bordered area BRDA is recorded. The
first bordered area BRDA#1 is composed of 4080 or more
physical segment blocks, and there is a need for the
first bordered area BRDA#1 to have a width of 1.0 mm or
more in a radial direction on the write-once type
information storage medium. FIG. 40 (b) shows an
example of setting an expanded drive test zone EDRTZ in
the data area DTA.
FIG. 40 (c) shows a state obtained after
finalizing a write-once information storage medium.
FIG. 40 (c) shows an example in which an expanded drive
test zone EDRTZ is incorporated in the data lead-out
area DTLDO, and further, an expanded spare area ESPA
has been set. In this case, a user data adding enable
range 205 is fully padded with the last border out area
BRDO.
FIG. 40 (d) shows a detailed data structure in the
border zone area BRDZ described above. Each item of
information is recorded in size units of one physical
segment blocks (physical segment block). Copy
information C_RMZ on the contents recorded in a
recording management zone is recorded at the beginning
of the border out area BRDO, and a border end mark
(Stop Block) STB indicating the border out area BRDOP
is recorded. Further, in the case the next border in
area BDI is reached, a first mark (Next Border Marker)
NBM indicating that a next border area reaches an
"Nl-th" physical segment block counted from a physical
segment block in which the border end mark (Stop Block)
STC has been recorded; a second mark NBM indicating
that a next border region reaches an "N2-th" physical
segment block; and a third mark NBM indicating that a
next border region reaches an "N3-th" mark NBM are
discretely recorded in a total of three locations on a
size by size basis of one physical segment block,
respectively. Updated physical format information
U_PFI is recorded in the next border-in area BRDI. In
a current DVD-R or a DVD-RW disk, in the case where a
next border is not reached (in the last border out area
BRDO), a location in which "a mark NBM indicating a
next border" should be recorded (a location of one
physical segment block size) shown in FIG. 40 (d) is
maintained as a "location in which no data is
recorded". If border closing is carried out in this
state, this write-once type information storage medium
(current DVD-R or DVD-RW disk) enters a state in which
reproduction can be carried out by using a conventional
DVD-ROM drive or a conventional DVD player. The
conventional DVD-ROM drive or the conventional DVD
player utilizes a recording mark recorded on this
write-once type information storage medium (current
DVD-R or DVD-RW disk) to carry out track shift
detection using the DPD (Differential Phase Detect)
technique. However, in the above described "location
in which no data is recorded", a recording mark does
not exist over one physical segment block size, thus
making it impossible to carry out track shift detection
using the DPD (Differential Phase Detect) technique.
Thus, there is a problem that a track servo cannot be
stably applied. In order to solve the above described
problem with the current DVD-R or DVD-RW disk, the
present embodiment newly employed methods for:
1) in the case where a next border area is
reached, recording data on a specific pattern in
advance in a "location in which the mark NBM indicating
a next border should be recorded"; and
2) carrying out an "overwriting process" in a
specific recording pattern partially and discretely
with respect to a location indicating "the mark NBM
indicating a next border" in which, in the case where a
next border area is reached, the data on the specific
pattern is recorded in advance, thereby utilizing
identification information indicating that "a next
border area is reached".
By setting a mark indicating a next border due to
overwriting, there is attained advantageous effect
that, even in the case where a next border area is
reached as shown in item (1), a recording mark of a
specific pattern can be formed in advance in a
"location in which the mark NBM indicating a next
border should be recorded", and, after border closing,
even if a read-only type information reproducing
apparatus carries out track shift detection in
accordance with the DPD technique, a track servo can be
stably applied. If a new recording mark is overwritten
partially on a portion at which a recording mark has
already been formed in a write-once type information
storage medium, there is a danger that the stability of
a PLL circuit shown in FIG. 11 is degraded in an
information recording/reproducing apparatus or an
information reproducing apparatus. In order to
overcome this danger, the present embodiment further
newly employs methods for:
3) when overwriting is carried out at a position
of "the mark NBM indicating a next border" of one
physical segment block size, changing an overwrite
state depending on a location contained in the same
data segment;
4) partially carrying out overwriting in a sync
data 432 and disabling overwriting on a sync code 431;
and
5) carrying out overwriting in a location
excluding data ID and IED.
As described later in detail, data fields 411 to
418 for recording user data and guard areas 441 to 448
are alternately recorded on an information storage
medium. A group obtained by combining the data fields
411 to 418 and the guard areas 441 to 448 is called a
data segment 490, and one data segment length coincides
with one physical segment block length. The PLL
circuit 174 shown in FIG. 11 facilitates PLL lead-in in
VFO areas 471 and 472 in particular. Therefore, even
if PLL goes out immediately before the VFO areas 471
and 472, PLL re-lead-in is easily carried out by using
the VFO areas 471 and 472, thus reducing an effect on a
whole system in the information recording/reproducing
apparatus or information reproducing apparatus. There
is attained advantageous effect that (3) an overwrite
state is changed depending on a location in a data
segment internal location, as described above, by
utilizing this state, and an overwrite amount of a
specific pattern is increased at a back portion close
to the VFO areas 471 and 472 contained in the same data
segment, thereby making it possible to facilitate
judgment of "a mark indicating a next border" and to
prevent degradation of the precision of a signal PLL at
the time of reproduction. As described in detail with
respect to FIGS. 83 (a) to 83 (f) and FIGS. 62 (a) and
62 (b), one physical sector is composed of a
combination of a location in which sync codes (SYO to
SY3) are arranged and the sync data 434 arranged
between these sync codes 433. The information
recording/reproducing apparatus or the information
recording apparatus samples sync codes 43 (SYO to SY3)
from a channel bit pattern recorded on the information
storage medium, and detects a boundary of the channel
bit pattern. As described later, position information
(physical sector numbers or logical sector numbers) on
the data recorded on the information storage medium is
sampled from data ID information. A data ID error is
sensed by using an IED arranged immediately after the
sampled information. Therefore, the present embodiment
enables (5) disabling overwriting on data ID and IED
and (4) partially carrying out overwriting in the sync
data 432 excluding the sync code 431, thereby enabling
detection of a data ID position and reproduction
(content-reading) of the information recorded in data
ID by using the sync code 431 in the "mark NMB
indicating a next border".
FIG. 39 shows another embodiment which is
different from that shown in FIG. 40 relating to a
structure of a border area in a write-once type
information storage medium. FIGS. 39 (a) and 39 (b)
show the same contents of FIGS. 40 (a) and 40 (b).
FIG. 39 (a) to 39 (d) are different from FIG. 40 (c) in
terms of a state that follows finalization of a writeonce
type information storage medium. For example, as
shown in FIG. 39 (c), after information contained in
the bordered area BRDA#3 has been recorded, in the case
where an attempt is made to achieve finalization, a
border out area BRDO is formed immediately after the
bordered area BDA#3 as a border closing process. Then,
a terminator area TRM is formed after the border out
area DRDO which immediately follows the bordered area
BRDA#3, thereby reducing a time required for
finalization. In the embodiment shown in FIG. 40,
there is a need for padding a region that immediately
precedes the expanded spare area ESPA with border out
area BRDO. There occurs a problem that a large amount
of time is required to form this border out area BRDO,
thereby expanding the finalization time. In contrast,
in the embodiment shown in FIG. 39 (c), a comparatively
short terminator area TRM is set in length; all of the
outer areas than the terminator TRM are redefined as a
data lead-out area NDTLDO; and an unrecorded portion
which is outer than the terminator TRM is set as a user
disable area 911. That is, when the data area DTA is
finalized, the terminator area TRM is formed at the end
of recording data (immediately after the border out
area BRDO). All the information on the main data
contained in this area is set to "OOh". Type
information on this area is set in an attribute of the
data lead-out area NDTLDO, whereby this terminator area
TRM is redefined as a new data lead-out area NDTLDO, as
shown in FIG. 39 (c). Type information on this area is
recorded in area type information 935 contained in data
ID, as described later. That is, the area type
information 935 contained in the data ID in this
terminator area TRM is set to "lOb", as shown in
FIGS. 50 (a) to 50 (d), thereby indicating that data
exists in the data lead-out area DTLDO. The present
embodiment is featured in that identification
information on a data lead-out position is set by the
data ID internal area type information 935. In an
information recording/reproducing apparatus or an
information reproducing apparatus shown in FIG. 11, let
us consider a case in which an information
recording/reproducing unit 141 has provided a random
access to a specific target position on a write-once
type information storage medium. Immediately after
random access, the information recording/reproducing
unit 141 must reproduce a data ID and decode a data
frame number 922 in order to know where on the writeonce
type information storage medium has been reached.
In the data ID, area type information 935 exists near
the data frame number 922. At the same time, it is
possible to immediately identify whether or not the
information recording/recording unit 141 exists in the
data lead-out area DTLDO merely by decoding this area
type information 935. Thus, a simplification and high
speed access control can be made. As described above,
identification information on the data lead-out area
DTLDO is provided by data ID internal setting of the
terminator area TRM, thereby making it easy to detect
the terminator area TRM.
As a specific example, in the case where the
border out area BRDO is set as an attribute of the data
lead-out area NDTLDO (that is, in the case where the
area type information 935 contained in the data ID of a
data frame in the border out BRDO is set to "lOb"), the
setting of this terminator area TRM is not provided.
Therefore, when the terminator area TRM is recorded,
the area having an attribute of the data lead-out area
NDTLDO, this terminator area TRM is regarded as part of
the data lead-out area NDTLDO, thus disabling recording
into the data area DTA. As a result, as in FIG. 39
(c), a user disable area 911 may remain.
In the present embodiment, the size of the
terminator area TRM is changed depending on a location
on a write-once type information storage medium,
thereby reducing a finalization time and achieving
efficient processing. This terminator area TRM
indicates an end position of recording data. In
addition, even in the case where this area is used in a
read-only apparatus, which carries out track shift
detection in accordance with a DPD technique, the
terminator area, is utilized to prevent overrun due to
a track shift. Therefore, a width in a radial
direction on the write-once type information storage
medium having this terminator area TRM (width of a
portion padded with the terminator area TRM) must be a
minimum of 0.05 nm or more because of the detection
characteristics of the read-only apparatus. A length
of one cycle on the write-once type information storage
medium is different depending on a radial position, and
thus, the number of physical segment blocks included in
one cycle is also different depending on the radial
position. Thus, the size of the terminator area TRM is
different depending on the physical sector number of a
physical sector which is positioned at the beginning of
the terminator area TRM, and the size of the terminator
area TRM increases as the physical sector go to the
outer periphery side. A minimum value of a physical
sector number of an allowable terminator area TRM must
be greater than "04FEOOh". This derived from a
restrictive condition in which the first bordered area
DRDA#1 is composed of 4080 or more physical segment
blocks, making it necessary for the first bordered area
BRDA#1 to have a width equal to or greater than 1.0 mm
in a radial direction on the write-once type
information storage medium. The terminator area TRM
must start from a boundary position of physical segment
blocks.
In FIG. 39 (d), a location in which each item of
information is to be recorded is set for each physical
segment block size for the reason described previously,
and a total of 64 KB user data recorded to be
distributed in 32 physical sectors is recorded in each
physical segment block. A relative physical segment
block number is set with respect to a respective one
item of information, as shown in FIG. 39 (d) , and the
items of information are sequentially recorded in the
write-once type information storage medium in ascending
order from the lowest relative physical segment number.
In the embodiment shown in FIGS. 39 (a) to 39 (d),
copies CRMD#0 to CRMD#4 of RMD, which are the same
contents, are overwritten five times in a copy
information recording zone C_TRZ of the contents
recorded in the recording management zone shown in
FIG. 40 (d). The reliability at the time of
reproduction is improved by carrying out such
overwriting, and, even if dust or scratch adheres onto
a write-once information storage medium, the copy
information CRMD on the contents recorded in the
recording management zone can be stably reproduced.
Although the border end mark STB shown in FIG. 39 (d)
coincides with a border end mark STB shown in FIG. 40
(d), the embodiment shown in FIG. 39 (d) does not have
the mark NBM indicating a next border, unlike the
embodiment shown in FIG. 40 (d). All the information
on the main data contained in reserved areas 901 and
902 is set to"00h".
At the beginning of the border-in area BRDI,
information which is completely identical to updated
physical format information U_PFI is multiply written
six times from N+l to N+6, configuring the updated
physical format information U_PFI shown in FIG. 40.
The thus updated physical format information U_PFI is
multiply written, thereby improving the reliability of
information.
In FIG. 39 (d), the present embodiment is featured
in that the recording management zone RMZ in the border
zone is provided in the border-in area BRDI. As shown
in FIG. 36 (a), the size of the recording management
zone RMZ contained in the data lead-in area DTLDI is
comparatively small. If the setting of a new bordered
area BRDA is frequently repeated, the recording
management data RMD recorded in the recording
management zone RMZ is saturated, making it impossible
to set a new bordered area BRDA midway. As in the
embodiment shown in FIG. 39 (d), there is attained
advantageous effect that a recording management zone
for recording the recording management data RMD
relating to the bordered area BRDA#3 that follows is
provided in the border-in area DRDI, whereby the
setting of a new bordered area BRDA can be provided a
number of times and the additional writing count in the
bordered area BRDA can be significantly increased. In
the case where the bordered area BRDA#3 that follows
the border-in area BRDI including the recording
management zone RMZ in this border zone is closed or in
the case where the data area DTA is finalized, it is
necessary to repeatedly record all the last recording
management data RMD into a spare area 273 (FIG. 38 (b))
established in an unrecorded state in the recording
management zone RMZ, and pad all the spare area with
the data. In thins manner, the spare area 273 in an
unrecorded state can be eliminated, a track shift (due
to DPD) at the time of reproduction in a read-only
apparatus can be prevented, and the reproduction
reliability of the recording management data RMD can be
improved by multiple recording of the recording
management data. All the data contained in a reserve
area 903 are set to "OOh".
Although the border out area BRDO serves to
prevent overrun due to a track shift in the read-only
apparatus while the use of DPD is presumed, there is no
need for the border-in area BRDI to have a
particularly large size other than having the updated
physical format information U_PFI and the information
contained in recording management zone RMZ in the
border zone. Therefore, an attempt is made to reduce
the size to the minimum in order to reduce a time
(required for border zone BRDZ recording) at the time
of setting a new bordered area BRDA. With respect to
FIG. 39 (a), before forming the border out area BRDO
due to border closing, there is a high possibility that
the user data additional writing enable range 205 is
sufficiently large, and a large number of additional
writing is carried out. Thus, it is necessary to
largely take a value of "M" shown in FIG. 39 (d) so
that recording management data can be recorded a number
of times in the recording management zone RMZ in a
border zone. In contrast, with respect to FIG. 39 (b),
in a state that precedes border closing of the bordered
area BRDA#2 and that precedes recording the border out
area BRDO, the user data additional writing enable
range 205 narrows, and thus, it is considered that not
the number of additional writings of the recording
management data to be additionally written in the
recording management zone RMZ in the border zone does
not increase so much. Therefore, the setting size "M"
of the recording management zone RMZ in the border-in
area BRDI that immediately precedes the bordered area
BRDA#2 can be taken to be relatively small. That is,
as a location in which the border-in area BRDI is
arranged goes to the inner periphery side, the number
of predicted additional writings of the recording
management data increases. As the location goes to the
outer periphery, the number of predicted additional
writings of the recording management data decreases.
Thus, the present embodiment is featured in that the
size of the border-in area BRDI is reduced. As a
result, the reduction of a time for setting a new
bordered area BRDA and processing efficiency can be
achieved.
A logical recording unit of the information
recorded in the bordered area BRDA shown in FIG. 40 (c)
is referred to as an R zone. Therefore, one bordered
area BRDA is composed of at least one or more R zones.
In a current DVD-ROM, as a file system, there are
employed a file system called a "UDF bridge" in which
both of file management information which conforms with
a UDF (Universal Disc Format) and file management
information which conforms with ISO 9660 are recorded
in one information storage medium at the same time. In
a file management method which conforms with ISO 9660,
there is a rule that one file must be continuously
recorded in an information storage medium. That is,
information contained in one file is disabled to be
divisionally arranged at a discrete position on an
information storage medium. Therefore, for example, in
the case where information has been recorded in
conformance with the above UDF bridge, all the
information configuring one file is continuously
recorded. Thus, it is possible to adapt this area in
which one file is continuously recorded so as to
configure one R zone.
FIG. 41 shows a data structure in the control data
zone CDZ and the R-physical information zone RIZ. As
shown in FIG. 41 (b), physical format information (PFI)
and disc manufacturing information (DMI) exist in the
control data zone CDZ, and similarly, an DMI (Disc
Manufacturing Information) and R PFI (R-Physical Format
Information) are contained in an R-physical information
zone RIZ.
Information 251 relating to a medium manufacture
country and medium manufacturer's nationality
information 252 are recorded in medium manufacture
related information DMI. When a commercially available
information storage medium infringes a patent, there is
a case in which an infringement warning is supplied to
such a country in which a manufacturing location exists
or an information storage medium is consumed (or used).
A manufacturing location (country name) is identified
by being obliged to record the information contained in
an information storage medium, and a patent
infringement warning is easily supplied, whereby an
intellectual property is guaranteed, and technical
advancement is accelerated. Further, other medium
manufacture related information 253 is also recorded in
the medium manufacture related information DMI.
The present embodiment is featured in that type of
information to be recorded is specified depending on a
recording location (relative byte position from the
beginning) in physical format information PFI or Rphysical
format information R_PFI. That is, as a
recording location in the physical format information
PFI or R-physical format information R_PFI, common
information 261 in a DVD family is recorded in an 32-
byte area from byte 0 to byte 31; common information
262 in an HD_DVD family which is the subject of the
present embodiment is recorded in 96 bytes from byte 32
to byte 127; unique information (specific information)
263 relating to various specification types or part
versions are recording in 384 bytes from byte 128 to
byte 511; and information corresponding to each
revision is recorded in 1536 bytes from byte 512 to
byte 2047. In this way, the information allocation
positions in the physical format information are used
in common depending on the contents of information,
whereby the locations of the recorded information are
used in common depending on medium type, thus making it
possible to carry out in common and simplify a
reproducing process of an information reproducing
apparatus or an information recording/reproducing
apparatus. The common information 261 in a DVD family
recorded in byte 0 to byte 31, as shown in FIG. 41D, is
divided into: information 267 recorded in common in all
of a read-only type information storage medium and a
rewritable-type information storage medium, and a
write-once type information storage medium recorded
from byte 0 to byte 16; and information 268 which is
recorded in common in the rewritable-type information
storage medium and the write-once type information
storage medium from byte 17 to byte 31 and which is not
recorded in the read-only type medium.
FIG. 55 shows another embodiment relating to a
data structure in the control data zone shown in
FIG. 41. As shown in FIG. 35C, the control data zone
CDZ is configured as part of an emboss bit area 211.
This control data zone CDZ is composed of 192 data
segments start from physical sector number 151296
(024FOOh). In the embodiment shown in FIG. 55, a
control data section CTDS composed of 16 data segments
and a copyright data section CPDS composed of 16 data
segments are arranged on two by two basis in the
control data zone CDZ, and a reserve area RSV is set
between these two sections. By allocating these
sections on a two by two basis, a physical distance
between the two sections is widened, and an effect
relevant to a burst error which occurs due to a scratch
of an information storage medium surface or the like is
reduced.
In one control data section CTDS, as shown in
FIG. 55 (c), physical sector information on first three
relative sector numbers "0" to "2" is recorded to be
repeated 16 times. Multiple writing is carried out
16 times, thereby improving the reliability of
recording information. Physical format information PFI
described in FIG. 42 or 54 is recorded in a first
physical sector in a data segment whose relative
physical sector number is "0". Disk manufacture
related information DMI is recorded in a second
physical sector in a data segment whose relative
physical sector number is "1". Furthermore, copyright
protection information CPI is recorded in the third
physical sector in the data segment in which relative
number of the physical sector is "2". A reserved area
RSV whose relative physical sector number is "3" to
"31" is reserved so as to be available in a system.
As the contents of the above described disk
manufacture related information DMI, a disk
manufacturer's name (Disc Manufacturer's name) is
recorded in 128 bytes from byte 0 to byte 127; and
information on a location in which a manufacturer
exists (information indicating where this disk has been
manufactured" is recorded in 128 bytes from byte 128 to
byte 255.
The above disk manufacturer's name is described in
ASCII codes. However, the ASCII codes available in use
as a disk manufacturer's name are limited to a starting
byte to "ODh" and "20h" to "7Eh". A disk manufacture's
name is described from the first byte 1 in this area,
and the remaining portions in this area are padded
(terminated) with data "ODh".
With respect to information on a location in which
the above disk manufacturer exists, the information
indicating where this disk has been manufactured, a
country or a region is described in the ASCII codes.
This area is limited to a starting byte to "ODh" and
"20h" to "7Eh" which are available ASCII codes as in
the disk manufacturer's name. The information on a
location in which a disk manufacturer exists is
described from the first byte I in this area, and the
remaining portions in this area are padded (terminated)
with data "ODh". Alternatively, another describing
method includes setting an allowable size in the range
of the first byte to "ODh" as the information on a
location in which a disk manufacturer exists. In the
case where the information on a location in which a
disk manufacturer exists is long, the information is
terminated at "ODh", and a region subsequent to "ODh"
may be padded with data "20h".
The reserved area RSV shown in FIG. 55 (c) is
fully padded with data "OOh".
FIG. 42 shows a comparison depending on a medium
type (read-only type, rewritable-type, or write-once
type) of information contained in the physical format
information PFI with the contents of specific
information contained in the physical format
information PFI or R-physical format information R_PFI
shown in FIG. 41 or FIG. 55. As information 267
recorded in common to all of the read-only type,
rewritable-type, and write-once type medium in the
common information 261 in the DVD family, there are
sequentially recorded from byte positions 0 to 16:
specification type (read-only, rewriting, or writeonce)
information and version number information;
medium size (diameter) and maximum allowable data
transfer rate information; a medium structure (single
layer or double layer or whether or not emboss pit,
additional writing area, or rewriting area exists); a
recording density (line density and track density)
information; allocation location information on data
region DTA; and information on whether or not burst
cutting area BCA exists (both of them exist in the
present embodiment).
As information 268 in common information 261 of a
DVD family and recorded in common to a rewriting type
and a write-once type, there are recorded: revision
number information for sequentially defining a maximum
recording speed from byte 28 to byte 31; revision
number information for defining a maximum recording
speed; a revision number table (application revision
number); class state information and expanded (part)
version information. The embodiment is featured in
that the information contained from byte 28 to byte 31
include revision information according to a recording
speed in a recording area of physical format
information PFI or R-physical format information R_PFI.
Conventionally, upon development of a medium featured
in that a medium recording speed such as x 2 or x 4
increases, there has been a very complicated
inconvenience that a specification is newly drafted
concurrently. In contrast, according to the present
embodiment, there are divisionally provided: a
specification (version book) in which a version is
changed when the contents have been significantly
changed; and a revision book in which the corresponding
revision is changed and issued, and only a revision
book is issued, the book having updated only revision
every time a recording speed is improved. In this
manner, an expanding function for a medium which
supports high speed recording and a specification can
be handled by a simple method called revision change.
Thus, in the case where a high speed recording
compatible medium has been newly developed, there is
attained advantageous effect that high speed recording
can be carried out. In particular, the present
embodiment is featured in that revision numbers can be
separately set by a maximum value and a minimum value
by separately providing a field of revision number
information defining a maximum recording speed of byte
17 and a field of revision number information defining
a minimum recording speed of byte 18. For example, in
the case where a recording film capable of carrying out
recording at a very high speed has been developed, that
recording film is often very expensive. In contrast,
as in the present embodiment, revision numbers are
separately set depending on a maximum value and a
minimum value of a recording speed, thereby increasing
options of recording mediums which can be developed.
As a result, there is attained advantageous effect that
a medium capable of carrying out high speed recording
or a more inexpensive medium can be supplied. An
information recording/reproducing apparatus according
to the present embodiment has in advance information on
an allowable maximum recording speed and an allowable
minimum recording speed for each revision. When an
information storage medium is mounted on this
information recording/reproducing apparatus, first, the
information recording/reproducing unit 141 shown in
FIG. 11 reads the information contained in this
physical format information PFI and R-physical format
information R_PFI. Based on the obtained revision
number information, there are detected by the control
unit 143: an allowable maximum speed and an allowable
minimum recording speed of an information storage
medium mounted with reference to information on an
allowable maximum recording speed and an allowable
minimum recording speed for each revision recorded in
advance in the memory unit 175; and recording is
carried out at an optimal recording speed based on the
result of the identification.
Now, a description will be given with respect to
the significance of specific information 263 of the
type and version of each of the specifications from
byte 128 to byte 511 shown in FIG. 41 (c) and the
significance of information content 264 which can be
set specific to each of the revisions from byte 512 to
byte 2047. That is, in the specific information 263 of
type and version of each of the specifications from
byte 128 to byte 511, the significance of the contents
of recording information at each byte position
coincides with a rewritable-type information storage
medium of a different type regardless of a write-once
type information storage medium. The information
content 264 which can be set specific to each of the
revisions from byte 512 to byte 2047 permits the fact
that if a revision is different from another in the
same type of medium as well as a difference between a
rewritable-type information storage medium and a writeonce
type information storage medium whose types are
different from each other, the significances of the
contents of recording information at byte positions are
different from each other.
As shown in FIG. 42, as information contents in
the specific information 263 on the type and version of
each of the specifications which coincide with each
other in significance of the contents of recording
information at byte positions between the
rewritable-type information storage medium and the
write-once type information storage medium whose types
are different from each other, there are sequentially
recorded: disk manufacturer's name information;
additional information from the disk manufacturer;
recording mark polarity information (identification of
"H-L" or "L-H"); line speed information at the time of
recording or reproduction; a rim intensity value of an
optical system along a radial direction; and
recommended laser power at the time of reproduction
(light amount value on recording surface).
In particular, the present embodiment is featured
in that recording mark polarity information (Mark
Polarity Descriptor (identification of "H-L" or "L-H")
is provided in byte 192. In the conventional
rewritable-type or write-once DVD disk, only a "H-L"
(High to Low) recording film whose light reflection
amount in a recording mark is low with respect to an
unrecorded state (a state in which reflection level is
relatively high: High) has been accepted. In contrast,
if a medium requires "high speed recording
compatibility", "price reduction" or "decrease in
cross-erase" and "increase in upper limit value of
rewriting count" which are physical properties, there
is a problem that the conventional "H-L" recording film
is insufficient. In contrast, the present embodiment
allows use of an "L-H" recording film whose light
reflection amount increases in a recording mark as well
as only an "H-L" recording film. Thus, there is
attained advantageous effect that the "L-H" recording
film as well as the conventional "H-L" film is
incorporated in the specification, and selecting
options of the recording films are increased, thereby
making it possible to achieve high speed recording or
to supply an inexpensive medium.
A specific method for mounting an information
recording/reproducing apparatus will be described
below. The specification (version book) or revision
book describe both of the reproduction signal
characteristics derived from the "H-L" recording film
and the reproduction signal characteristics derived
from the "L-H" recording film. Concurrently, the
corresponding circuits are provided on a two by two
basis in the PR equalizing circuit 130 and Viterbi
decoder 156 shown in FIG. 11. When an information
storage medium is mounted in the information
reproduction unit 141, first, the slice level detector
circuit 132 for reading the information contained in
the system lea-in area SYLDI is started up. This slice
level detector circuit 132 reads information on
polarity of a recording mark recorded in this 192 byte
(identification of "H-L" or "L-H"); and then make
judgment of "H-L" or "L-H". In response to the
judgment, after the PR equalizing circuit 130 and a
circuitry contained in the Viterbi decoder 156 has been
switched, the information recorded in the data lead-in
area DTLDI or data area DTA is reproduced. The above
described method can read the information contained in
the data lead-in area DTLDI or data area DTA
comparatively quickly, and moreover, precisely.
Although revision number information defining a maximum
recording speed is described in byte 17 and revision
number information defining a minimum recording speed
is described in byte 18, these items of information are
merely provided as range information defining a maximum
and a minimum. In the case where the most stable
recording is carried out, there is a need for optimal
line speed information at the time of recording, and
thus, the associated information is recorded in
byte 193.
The present embodiment is featured in that
information on a rim intensity value of an optical
system along a circumferential direction of byte 194
and information on a rim intensity value of an optical
system along in a radial direction of byte 195 is
recorded as optical system condition information at a
position which precedes information on a variety of
recording conditions (write strategies) included in the
information content 264 set specific to each revision.
These items of information denote conditional
information on an optical system of an optical head
used when identifying a recording condition arranged at
the back side. The rim intensity used here denotes a
distribution state of incident light incident to an
objective lens before focusing on a recording surface
of an information storage medium. This intensity is
defined by a strength value at a peripheral position of
an objective lens (iris face outer periphery position)
when a center intensity of an incident light intensity
distribution is defined as "1". The incident light
intensity distribution relevant to an objective lens is
not symmetrical on a point to point basis; an
elliptical distribution is formed; and the rim
intensity values are different from each other
depending on the radial direction and the
circumferential direction of the information storage
medium. Thus, two values are recorded. As the rim
intensity value increases, a focal spot size on a
recording surface of the information storage medium is
reduced, and thus, an optimal recording power condition
changes depending on this rim intensity value. The
information recording/reproducing apparatus recognizes
in advance the rim intensity value information
contained in its own optical head. Thus, this
apparatus reads the rim intensity values of the optical
system along the circumferential direction and the
radial direction, the value being recorded in the
information storage medium, and compares values of its
own optical head. If there is no large difference as a
result of the comparison, a recording condition
recorded at the back side can be applied. If there is
a large difference, there is a need for ignoring the
recording condition recorded at the back side and
starting identifying an optimal recording condition
while the recording/reproducing apparatus carries out
test writing by utilizing the drive test zone DRTZ
shown in FIGS. 35B, 35C, 37A to 37F.
Therefore, there is a need for quickly making a
decision as to whether to utilize the recording
condition recorded at the back side or whether to start
identifying the optimal recording condition while
ignoring the information and carrying out test writing
by oneself. As shown in FIG. 42, there is attained
advantageous effect that the rim intensity information
can be read, and then judgment can be made at a high
speed as to whether or not the receding condition
arranged later is met by arranging conditional
information on an optical system identified at a
preceding position with respect to a position at which
the recommended recording condition has been recorded.
As described above, according to the present
embodiment, there are divisionally provided: a
specification (version book) in which a version is
changed when the contents have been significantly
changed; and a revision book in which the corresponding
revision is changed and issued, and only a revision
book is issued, the book having updated only revision
every time a recording speed is improved. Therefore,
if a revision number is different from another, a
recording condition in a revision book changes. Thus,
information relating to a recording condition (write
strategy) is mainly recorded in the information content
264 which can be set specific to each of the revisions
from byte 512 to byte 2047. As is evident from
FIG. 42, the information content 264 which can be set
specific to each of the revisions from byte 512 to byte
2047 permits the fact that if a revision is different
from another in the same type of medium as well as a
difference between a rewritable-type information
storage medium and a write-once type information
storage medium whose types are different from each
other, the significances of the contents of recording
information at byte positions are different from each
other.
Definitions of peak power, bias power 1, bias
power 2, and bias power 3 shown in FIG. 42 coincide
with power values defined in FIG. 18. An end time of a
first pulse shown in FIG. 42 denotes Tgjrp defined in
FIG. 18; a multi-pulse interval denotes Tjyjp defined in
FIG. 18; a start time of a last pulse denotes TgLp
defined in FIG. 38, and a period of bias power 2 of 2T
mark denotes T^c defined in FIG. 18.
FIG. 54 shows another embodiment relating to a
data structure in each of physical format information
and R-physical format information. Further, FIG. 54
comparatively describes "updated physical format
information". In FIG. 54, byte 0 to byte 31 are
utilized as a recording area of common information 269
contained in a DVD family, and byte 32 and subsequent
are set for each specification.
In a write-once type information storage medium,
as shown in FIG. 35C, with respect to R-physical format
information recorded in an R-physical information zone
RIZ contained in the data lead-in area DTLDI, border
zone start position information (first border outermost
periphery address) is added to the physical format
information PFI (copy of HD_DVD family common
information), and the added information is described.
In the updated physical format information U_PFI,
updated in the border-in area BRDI shown in FIG. 40 or
39, start position information (self-border outermost
periphery address) is added to the physical format
information (copy of HD_DVD family common information),
and the added information is recorded. In FIG. 42,
this border zone start position information is recorded
from byte 197 to byte 204. In contrast, the embodiment
shown in FIG. 54 is featured in that information is
recorded at byte 133 to byte 140 which are positions
preceding information relating to a recording condition
such as peak power or bias power 1 (information content
264 which can be set specific to each revision), the
position following the common information 269 contained
in the DVD family. The updated start position
information is also arranged in byte 133 to byte 140
which are positions preceding information relating to a
recording condition such as peak power or bias power 1
(information content 264 which can be set specific to
each revision), the position following the common
information 269 contained in the DVD family. If
revision number is upgraded and a recording condition
for high precision is required, there is a possibility
that the recording condition information contained in
the rewritable-type information storage medium uses
byte 197 to byte 207. In this case, as in the
embodiment shown in FIG. 42, if the border zone start
position information for R-physical format information
recorded in the write-once type information storage
medium is arranged in byte 197 to byte 204, there is a
danger that a correlation (compatibility) between the
rewritable-type information storage medium and the
write-once type information storage medium relating to
the arranged position of the recording condition is
distorted. As shown in FIG. 54, there is attained
advantageous effect that the border zone start position
information and the updated start position information
are arranged in byte 133 to byte 140, thereby making it
possible to record a correlation (compatibility) in
recording position of a variety of information between
the rewritable-type information storage medium and the
write-once type information storage medium even if an
amount of information relating to a recording condition
will be increased in the future. With respect to the
specific contents of information relating to the borer
zone start position information, the start position
information on the border out area BRDO situated at the
outside of the (current) bordered area BRDA currently
used in byte 133 to byte 136 is described in PSN
(Physical Sector Number); and border-in area BRDI start
position information relating to the bordered area BRDA
to be used next is described in the physical sector
number (PSN) in byte 137 to byte 140.
The specific contents of information relating to
the updated start position information indicate the
latest border zone position information in the case
where a bordered area BRDA has been newly set. The
start position information on the border out area BRDO
situated at the outside of the (current) bordered area
BRDA currently used in byte 133 to byte 136 is
described in PSN (Physical Sector Number); and the
start position information on the border-in area BRDI
relating to the bordered area BRDA to be used next is
described in the sector number (PSN) in byte 137 to
byte 140. In the case where recording cannot be
carried out in the next bordered area BRDA, this area
(ranging from byte 137 to byte 140) is padded with all
"OOh".
As compared with the embodiment shown in FIG. 42,
in the embodiment shown in FIG, 54, "medium
manufacturer's name information" and "additional
information from medium manufacturer" are erased, and
recording mark polarity information (identification of
"H-L" or "L-H") is arranged in 128 byte and subsequent.
FIG. 43 shows a comparison of the contents of
detailed information recorded in the allocation
location information on the data area DTA recorded in
byte 4 to byte 15 shown in FIG. 42 or 54. The start
position information on the data area DTA is recorded
in common regardless of identification of medium type,
physical format information PFI, and R-physical format
information R_PFI. As information indicating an end
position, end position information on the data area DTA
is recorded in a read-only type information storage
medium.
End position information on an additional writing
enable range of the user data is recorded in the
physical format information PFI contained in the writeonce
type storage medium. This positional information
denotes a position that immediately precedes point 5 in
an example shown in FIG. 37E, for example.
In contrast, the R-physical format information
R_PFI contained in the write-once type information
storage medium records the end position information on
the recorded data contained in the corresponding
bordered area BRDA.
Further, the read-only type information storage
medium records the end address information contained in
"layer 0" which is a front layer when seen from the
reproduction optical system; and the rewritable-type
information storage medium records information on a
differential value of each item of start position
information between a land area and a groove area.
As shown in FIG. 35C, a recording management zone
RMZ exists in the data lead-in area DTLDI. In
addition, as shown in FIG. 40 (d), the associated copy
information exists in the border-out zone BRDO as copy
information C_RMZ indicating the contents recorded in
the recording management zone. This recording
management zone RMZ records RMD (Recording Management
Data) having the same data size as one physical segment
block size, as shown in FIG. 36 (b), so that new
recording management data RMD updated every time the
contents of the recording management data RMD is
updated can be sequentially added backwardly. A
detailed data structure in such one item of recording
management data RMD is shown in each of FIGS. 44, 45,
46, 47, 48 and 49. The recording management data RMD
is further divided into fine RMD field information RMDF
of 2048 byte size.
The first 2048 bytes in the recording management
data are provided as a reserved area. The next RMD
field 0 of 2048 byte size sequentially allocates:
format code information of recording management data
RMD; medium state information indicating a state of the
target medium, i.e., (1) in an unrecorded state, (2) on
the way of recording before finalizing, or (3) after
finalizing; unique disk ID (disk identification
information); allocation position information on the
data region DTA; allocation position information on the
latest (updated) data area DTA; and allocation position
information on recording management data RMD. The
allocation position information on the data area
records information indicating a user data additional
writing enable range 204 (FIG. 37D), i.e., start
position information on the data area DTA and the end
position information on the user data recording enable
range 204 at the time of an initial state. In the
embodiment shown in FIG. 37D, this information
indicates a position that immediately precedes point p.
The present embodiment, as shown in FIGS. 37E and
37F, is featured in that an expanded drive test zone
EDRTZ and an expanded spare area ESPA can be
additionally set in the user data additional writing
enable range 204. However, such expansion narrows a
user data additional writing enable range 205. The
present embodiment is featured in that associated
information is recorded in "allocation position
information on the latest (updated) data area DTA" so
as not to additionally write the user data in these
expanded areas EDRTZ and ESPA. That is, it is possible
to identify whether or not the expanded drive test zone
EDRTZ has been expanded based on the identification
information on the presence or absence of the expanded
drive test zone EDRTZ, and it is possible to identify
whether or not the expanded spare area ESPA has been
expanded based on identification information on the
presence or absence of the expanded spare area ESPA.
Further, the recording enable range information
relating to the user data additional writing enable
range 205 managed in the recording management data RMD
includes an end position of the latest user data
recording enable range 205 recorded in the allocation
position information on the data area DTA. Therefore,
the user data recording enable range 205 shown in
FIG. 37F can be identified immediately, enabling high
speed detection of a size of an unrecorded area in
which recording can be carried out in the future (the
residual amount of unrecorded area). In this manner,
for example, there is attained advantageous effect that
a transfer rate at the time of optimal recording is set
in conformance with the user specified image recording
reserved time, thereby making it possible to fully
record an image in a medium during the user specified
image recording reserved time. By way of example of
the embodiment shown in FIG. 37D, "the end position of
the latest user data recording enable range 205"
denotes a position that precedes point 8. These items
of positional information can be described in ECC block
address numbers according to another embodiment instead
of being described in physical sector numbers. As
described later, in the present embodiment, one ECC
block is composed of 32 sectors. Therefore, the least
significant five bits of the physical sector number of
a sector arranged at the beginning in a specific ECC
block coincides with that of a sector arranged at the
start position in the adjacent ECC block. In the case
where a physical sector number has been assigned so
that the least significant five bits of the physical
sector of the sector arranged at the beginning in the
ECC block is "00000", the values of the least
significant six bits or more of the physical sector
numbers of all the sectors existing in the same ECC
block coincide with each other. Therefore, address
information obtained by eliminating the least
significant five bit data of the physical sector
numbers of the sectors existing in the same ECC block
as above and sampling only data of the least
significant six bit and subsequent is defined as ECC
block address information (or ECC block address
number). As described later, the data segment address
information (or physical segment block number
information recorded in advance by wobble modulation
coincides with the above ECC block address. Thus, when
the positional information contained in the recording
management data RMD is described in the ECC block
address numbers, there is attained advantageous effects
described below:
1) An access to an unrecorded area is accelerated
in particular:
- A differential calculation process is
facilitated because a positional information unit of
the recording management data RMD coincides with an
information unit of data segment addresses recorded in
advance by wobble modulation; and
2) A management data size in the recording
management data RMD can be reduced:
- The number of bits required for describing
address information can be reduced by 5 bits per
address.
As described later, a single physical segment
block length coincides with a one data segment length,
and the user data for one ECC block is recorded in one
data segment. Therefore, an address is expressed as an
"ECC block address number"; an "ECC block address"; a
"data segment address", a "data segment number", or a
"physical segment block number" and the like. These
expressions have the same meaning.
As shown in FIG. 44, in the allocation position
information on the recording management data RMD
existing in RMD field 0, size information in that the
recording management zone RMZ capable of sequentially
additionally writing the recording management data RMD
is recorded in ECC block units or in physical segment
block units. As shown in FIG. 36 (b), one recording
management zone RMD is recorded on one by one physical
segment block basis, and thus, based on this
information, it is possible to identify how many times
the updated recording management data RMD can be
additionally written in the recording management zone
RMZ. Next, a current recording management data number
is recorded in the recording management zone RMZ. This
denotes number information on the recording management
data RMD which has been already recorded in the
receding management zone RMZ. For example, assuming
that this information corresponds to the information
contained in the recording management data RMD#2 as an
example shown in FIG. 36 (b), this information
corresponds to the second recorded recording management
data RMD in the receding management zone RMZ, and thus,
a value "2" is recorded in this field. Next, the
residual amount information contained in the recording
management zone RMZ is recorded. This information
denotes information on the item number of the recording
management data RMD which can be further added in the
recording management zone RMZ, and is described in
physical segment block units (= ECC block units = data
segment units). Among the above three items of
information, the following relationship is established.
[Size information having set RMZ therein]
= [Current recording management data number]
+ [residual amount in RMZ]
The present embodiment is featured in that the use
amount or the residual amount information on the
recording management data RMD contained in the
recording management zone RMZ is recorded in a
recording area of the recording management data RMD.
For example, in the case where all information is
recorded in one write-once type information storage
medium once, the recording management data RMD may be
recorded only once. However, in the case where an
attempt is made to repeatedly record additional writing
of the user data (additional writing of the user data
in the user data additional writing enable range 205 in
FIG. 37F) very finely in one write-once type
information storage medium, it is necessary to
additionally write recording management data RMD
updated every time additional writing is carried out.
In this case, if the recording management data RMD is
frequently additionally written, the reserved area 273
shown in FIG. 36 (b) is eliminated, and the information
recording/reproducing apparatus requires
countermeasures against this elimination. Therefore,
the use amount or residual amount information on the
recording management data RMD contained in the
recording management zone RMZ is recorded in a
recording area of the recording management data RMD,
thereby making it possible to identify in advance a
state in which additional writing in the recording
management zone RMZ cannot be carried out and to take
action by the information recording/reproducing
apparatus earlier.
As shown in FIGS. 37E to 37F, the present
embodiment is featured in that the data lead-out area
DTLDO can be set in the form such that the expanded
drive test zone EDRTZ is included (FIG. 1 (E4)). At
this time, the start position of the data lead-out area
DTLDO changes from point P to point £. In order to
manage this situation, there is provided a field for
recording the start position information on the data
lead-out area DTLDO in the allocation position
information of the latest (updated) data area DTA of
the RMD field shown in FIGS. 44 to 49. As described
previously, a drive test (test writing) is basically
recorded in cluster units which can be expanded in data
segment (ECC block) units. Therefore, although the
start position information on the data lead-out area
DTLDO is described in the ECC block address numbers,
this information can be described in the physical
sector number or physical segment block number, data
segment address, or ECC block address of a physical
sector first arranged in this first ECC block according
to another embodiment.
In an RMD field 1, there are recorded: update
history information on an information
recording/reproducing apparatus in which recording of
the corresponding medium has been carried out. This
information is described in accordance with a format of
all recording condition information contained in
information 264 (FIG. 42) in which manufacturer
identification information for each information
recording/reproducing apparatus; serial numbers and
model numbers described in ASCII codes; date and time
information when recording power adjustment using a
drive test zone has been made; and recording condition
information provided at the time of additional writing
can be set specific to each revision.
An RMD field 2 is a user available area so that a
user can record information recorded contents (or
contents to be recorded), for example.
The start position information of each border zone
BRDZ is recorded in an RMD field 3. That is, as shown
in FIG. 45, the start position information from the
start to the fiftieth border out areas BTDOs is
described in the physical sector numbers.
For example, in the embodiment shown in FIG. 40
(c), the start position of the first border out area
BRDO indicates a position of point r|, and the start
position of the second BRDO indicates a position of
point 9.
The positional information on an expanded drive
test zone is recorded in an RMD field 4. First, there
are recorded: the end position information on a
location which has already been used for test writing
in the drive test zone DRTZ which exists in the data
lead-in area DTLDI described in FIG. 36 (c); and the
end position information on a location which has
already been used for test writing in the drive test
zone DRTZ which exists in the data lead-out area DTLDO
described in FIGS. 37D to 37F. In the drive test zone
DRTZ, the above position information is sequentially
used for test writing from the inner periphery side
(from the lowest physical sector number) to the outer
periphery direction (in a direction in which the
physical sector number is higher). Test writing is
carried out in cluster units which are units of
additional writing, as described later, and thus, ECC
block units are used as location units. Therefore, in
the case where the end position information on the
location which has been already used for test writing
is described in the ECC address numbers or is described
in the physical sector numbers, there are described a
physical sector number of a physical sector arranged at
the end of the ECC block which has been used for test
writing. Because a location used for test writing once
has already been described, in the case where next test
writing is carried out, such test writing is carried
out from a next of the end position which has already
been used for test writing. Therefore, the information
recording/reproducing apparatus can identify
momentarily from where test writing should be started
by using the end position information (= a use amount
in the drive test zone DRTZ) on a location which has
already been used in the above drive test zone DRTZ.
In addition, based on that information, this apparatus
can judge whether or not a free space in which next
test writing can be carried out exists in the drive
test zone DRTZ. The drive test zone DRTZ which exists
in the data lead-in area DTLDI records: flag
information indicating whether or not area size
information indicating that additional writing can be
carried out; flag information indicating that this
drive test zone DRTZ has been used up or area size
information indicating that additional test writing can
be further carried out in the drive test zone DRTZ
which exists in the data lead-out area DLTDI; and area
size information indicating that additional test
writing can further be carried out in the drive test
zone DRTZ which exists in the data lead-out area DTLDO
or flag information indicating whether or not this
drive test zone DRTZ has been used up. The size of the
drive test zone DRTZ which exists in the data lead-in
area DTLDI and the size of the drive test zone DRTZ
which exists in the data lead-out area DTLDO are
identified in advance, thus making it possible to
identify the size (residual amount) of an area in which
additional test writing can be carried out in the drive
test zone DRTZ only based on the end position
information on a location which has already been used
for test writing in the drive test zone DRTZ which
exists in the data lead-in area DTLDI or in the drive
test zone DRTZ which exists in the data lead-out area
DTLDO. However, this information is provided in the
recording management data RMD, thereby making it
possible to identify the residual amount in the drive
test zone DRTZ immediately and to reduce a time
required for judging whether or not to newly set the
expanded drive test zone EDRTZ. According to another
embodiment, in this field, it is possible to record:
flag information indicating whether or not this drive
test zone DRTZ has been used up instead of area size
(residual amount) information indicating that
additional writing can further be carried out in the
drive test zone DRTZ. If a flag has already been set
to identify momentarily that the above test zone has
already been used up, it is possible to preclude a
danger that test writing is carried out in this area.
Additional setting count information on the next
expanded drive test zone EDRTZ is recorded in the RMD
field 4. In the embodiment shown in FIG. 37E, the
expanded drive test zones EDRTZs are set in two zones,
i.e., an expanded drive test zone 1 EDRTZl and an
expanded drive test zone 2 EDRTZ2, and thus,
"additional setting count of the expanded drive test
zone EDRTZ = 2" is established. Further, range
information for each expanded drive test zone EDRTZ and
range information which has already been used for test
writing are recorded in the RMD field 4. In this way,
the positional information on the expanded drive test
zone can be managed in the recording management data
RMD, thereby enabling expansion setting of the expanded
drive test zone EDRTZ a plurality of times. In
addition, in a write-once type information storage
medium, the positional information on the expanded
drive test zone EDRTZ which has been sequentially
expanded can be precisely managed in the form of
updating and additional writing of the recording
management data RMD, and it is possible to preclude a
danger that the user data is overwritten on the
expanded drive test zone EDRTZ while user data
additional writing enable range 204 (FIG. 37D) is
mistakenly determined. As described above, test
writing units are also recorded in cluster units (ECC
block units), and thus, the range of each expanded
drive test zone EDRTZ is specified in ECC block address
units. In the embodiment shown in FIG. 37E, the start
position information on the first set expanded drive
test zone EDRTZ indicates point y because the expanded
drive test zone 1 EDRTZl has been first set; and the
end position information on the first set expanded
drive test zone EDRTZ corresponds to a position that
immediately precedes point p. Positional information
units are described in the address numbers or physical
sector numbers similarly. While the embodiment of
FIGS. 44 and 45 shows the end position information on
the expanded drive test zone EDRTZ, size information on
the expanded drive test zone EDRTZ may be described
without being limited thereto. In this case, the size
of the first set expanded drive test zone 1 EDRTZl is
set to "p-y". The end position information on a
location which has already been used for test writing
in the first set expanded drive test zone EDRTZ is also
described with the ECC block address number or physical
sector number. Then, the area size information
(residual amount) in which additional test writing can
be carried out in the first set expanded drive test
zone EDRTZ. The size of the expanded drive test zone 1
EDRTZl and the size of the area, which has already been
used therein, is already been identified based on the
above described information. Thus, the area size
(residual amount) in which additional test writing can
be carried out is already obtained. By providing this
field, it is possible to identify immediately whether
or not a current drive test zone will suffice when a
new drive test (test writing) is carried out. In
addition, it is possible to reduce a judgment time
required for determining additional setting of a
further expanded drive test zone EDRTZ. In this field,
there can be recorded area size (residual amount)
information indicating that additional writing can be
carried out. According to another embodiment, in this
field it is possible to set flag information indicating
whether or not this expanded drive test zone EDRTZ has
been used up. It is possible to preclude a danger that
test writing is mistakenly carried out in this area, as
long as a flag is set to momentarily identify that the
test zone has already been used up.
A description will be given with respect to an
example of a processing method for newly setting an
expanded drive test zone EDRTZ by the information
recording/reproducing apparatus shown in FIG. 11 and
carried out test writing in the zone.
1) A write-once type information storage medium is
mounted on an information recording/reproducing
apparatus.
2) Data formed in the burst cutting area BCA is
reproduced by the information recording/reproducing
unit 141; the recorded data is supplied to the control
unit 143; and the information is decoded in the control
unit 143, and it is determined whether or not
processing can proceeds to a next step.
3) Information recorded in the control data zone
CDZ in the system lead-in area SYLDI is recorded by the
information recording/reproducing unit 141, and the
reproduced information is transferred to the control
unit 143.
4) Values of rim intensities (in bytes 194 and 195
shown in FIG. 42) when a recommended recording
condition has been identified in the control unit 143
are compared with a value of rim intensity of an
optical head used at the information
recording/reproducing unit 141; and an area size
required for test writing is identified.
5) The information contained in recording
management data is reproduced by the information
recording/reproducing unit 141, and the reproduced
information is transferred to the control unit 143.
The control section decodes the information contained
in the RMD field 4 and determines whether or not there
is a margin of an area size required for test writing,
the size being identified in step 4). In the case
where the judgment result is affirmative, processing
proceeds to step 6). Otherwise, processing proceeds to
step 9).
6) A location for starting test writing is
identified based on end position information on a
location which has already been used for test writing
in the drive test zone DRTZ or expanded drive test zone
EDRTZ used for test writing from the RMD field 4.
7) Test writing is executed by the size identified
in step 4) from the location identified in step 6).
8) The number of locations used for test writing
has been increased in accordance with the processing in
step 7), and thus, recording management data RMD
obtained by rewriting the end position information on
the locations which has already been used for test
writing is temporarily stored in the memory unit 175,
and processing proceeds to step 12).
9) The information recording/reproducing unit 141
reads information on "end position of the latest user
data recording enable range 205" recorded in the RMD
field 0 or "end position information on the user data
additional writing enable range" recorded in the
allocation location information on the data area DTA
contained in the physical formed shown in FIG. 43; and
the control unit 143 further internally sets the range
of a newly set expanded drive test zone EDRTZ.
10) Information on "end position of the latest
used data recording enable range 205" recorded in the
RMD field 0 based on the result described in step 9) is
updated and additional setting count information on the
expanded drive test zone EDRTZ contained in the RMD
field 4 is incremented by one (that is, the count is
added by 1); and further, the memory unit 175
temporarily stores the recording management data RMD
obtained by adding the start/end position information
on the newly set expanded drive test zone EDRTZ.
11) Processing moves from step 7) to step 12).
12) Required user information additionally written
into the user data additional writing enable range 205
under an optimal recording condition obtained as a
result of test writing carried out in step 7).
13) The memory unit 175 temporarily stores the
recording management data RMD updated by additionally
writing the start/end position information (FIG. 47)
contained in an R zone which has been newly generated
in response to step 12).
14) The control unit 143 controls the information
recording/reproducing unit 141 to additionally record
the latest recording management data RMD temporarily
stored in the memory unit 175, in the reserved area 273
(for example, FIG. 36 (b)) contained in the recording
management zone RMZ.
As shown in FIG. 47, positional information on the
expanded spare area ESPA is recorded in an RMD field 5.
In the write-once type information storage medium, a
spare area can be expanded, and the positional
information on that spare area is managed in the
position management data RMD. In the embodiment shown
in FIG. 37E, the expanded spare area ESPA is set in two
areas, i.e., an expanded spare area 1 ESPA1 and an
expanded spare area 2 ESPA2, and thus, "the number of
additional settings of the expanded space area ESPA" is
set to "2". The start position information on the
first set expanded spare area ESPA corresponds to at a
position of point 8; the end position information on
the second set expanded spare area ESPA corresponds to
at a position that precedes point y; the end position
information on the first set expanded spare area ESPA
corresponds to at a position that precedes point £; and
the end position information on the second set expanded
spare area ESPA corresponds to at a position of
point E.
The information relating to defect management is
recorded in the RMD field 5 shown in FIG. 47. A first
field in the RMD field 5 shown in FIG. 47 records ECC
block number information or physical segment block
number information which has already been used for
substitution in the adjacent area to the data lead-in
area DTLDI. In the present embodiment, a substituting
process is carried out in ECC block units with respect
to a defect area found in the user data additional
writing range 204. As described later, one data
segment configuring one ECC block is recorded in one
physical segment block area, and thus, the substitution
count which has already been done is equal to the
number of ECC blocks which has already been used (or
number of physical segment blocks and number of data
segments). Therefore, the units of information
described in this field are obtained as ECC block units
or physical segment block units and data segment units.
In the write-once type information storage medium, in
the spare area SPA or expanded pare area ESPA, a
location used as a replacing process may be often used
sequentially from the inner periphery side having the
lowest ECC block address number. Therefore, with
respect to the information contained in this field, in
another embodiment, it is possible to describe an ECC
block address number as the end position information on
a location which has already been used for
substitution. As shown in FIG. 47, with respect to the
first set expanded spare area 1 ESPA1 and the second
set expanded spare area 2 ESPA2 as well, there exist
fields for recording similar information ("ECC block
number information or physical segment block number
information which have already been used for
substitution in the first set expanded spare area ESPA
or end position information (ECC block address number)
on a location which has been used for substitution";
and "ECC block number information or physical segment
block number information which have already been used
for substitution in the second set expanded spare area
ESPA or end position information (ECC block address
number) on a location which has been used for
substitution".
Using these items of information, the following
advantageous effects are attained:
1) A spare location to be newly set with respect
to a defect area found in the user data additional
writing enable range 205 is identified immediately when
next substituting process is carried out.
- New substitution is carried out immediately
after the end position of a location which has already
been used for substitution.
2) The residual amount in the spare area SPA or
expanded spare area ESPA is obtained by calculation and
(in the case where the residual amount is
insufficient) , it is possible to identify necessity of
setting a new expanded spare area ESPA.
The size of the spare area SPA adjacent to the
data lead-in area DTLDI is identified in advance, and
thus, the residual amount in the spare area SPA can be
calculated if there exists information relating to the
number of ECC blocks which have already been used in
the spare area SPA. However, the residual amount can
be identified immediately by providing a recording
frame of the ECC block number information or physical
segment block number information in an unused location
available for future substitution, which is residual
amount information contained in the spare area SPA.
Thus, it is possible to reduce a time required for
judgment of the necessity of providing settings
relating to a further expanded spare area ESPA. For a
similar reason, there is provided a frame capable of
recording "residual amount information contained in the
first set expanded spare area ESPA and "residual amount
information contained in the second set expanded spare
area ESPA. In the present embodiment, a spare area SPA
is extensible in the write-once type information
storage medium, and the associated position information
is managed in the recording management data RMD. As
shown in FIGS. 37A to 37F, it is possible to
extensively set an expanded spare area 1 ESPA1 and an
expanded spare area 2 ESPA2 or the like at an arbitrary
start position and at an arbitrary size as required in
the user data additional writing enable range 204.
Therefore, the additional setting count information on
the expanded spare area ESPA is recorded in the RMD
field 5, making it possible to set the start position
information on the first set expanded spare area ESPA
or the start position information on the secondly set
expanded spare area ESPA. These items of start
position information are described in physical sector
numbers or ECC block address numbers (or physical
segment block numbers or data segment addresses). In
the embodiment shown in FIGS. 44 and 45, "the end
position information on the first set expanded spare
area ESPA" or "the end position information on the
second set expanded spare area ESPA" are recorded as
information for specifying the range of the expanded
spare area ESPA. However, in another embodiment, in
stead of these items of end position information, size
information on the expanded spare area ESPA can be
recorded by the ECC block number or physical segment
block number, data segment number, and ECC block number
or physical sector number.
Defect management information is recorded in an
RMD field 6. The present embodiment uses a method for
improving reliability of information to be recorded in
an information storage medium, the information relating
to defect processing, in the following two modes:
1) A conventional "replacing mode" for recording
in a spare location information to be recorded in a
defect location; and
2) A "multiplying mode" for recording the same
contents of information twice in a location which is
different from another one on an information storage
medium, thereby improving reliability.
Information as to which mode processing is carried
out is recorded in "type information on defect
management processing" contained in secondary defect
list entry information contained in the recording
management data RMD as shown in FIG. 48. The contents
of secondary defect list entry information are as
follows:
1) In the case of the conventional replacing mode
Type information on defect management processing
is set to "01" (in the same manner as in conventional
DVD-RAM);
The "positional information on a replacement
source ECC block" used here denotes positional
information on an ECC block found as a defect location
in the user data additional writing enable range 205,
and information to be essentially recorded in the range
is recorded in a spare area or the like without being
recorded in the above range; and
The "positional information on a replacement
destination ECC block" used here indicates positional
information on a location of a replacement source to be
set in the spare area SPA or expanded spare area I
ESPA1, and an expanded spare area 2 ESPA2 shown in
FIG. 37E, and the information to be recorded in a
defect location, the information being found in the
additional writing enable range 205, is recorded in the
above area.
2) In the case of the multiplying mode
Type information on defect management processing
is set to "10";
The "positional information on replacement source
ECC block" denotes a non-defect location, and indicates
position information in which target information is
recorded and the information recorded therein can be
precisely reproduced; and
The "positional information on replacement
destination ECC block" indicates positional information
on a location in which the completely same contents as
the information recorded in the above described
"positional information on replacement source ECC
block" are recorded for the purpose of multiplication
set in the spare area SPA or expanded spare area 1
ESPA1 and expanded spare area 2 ESPA 2 shown in
FIG. 37E.
In the case where recording has been carried out
in the above described "1) conventional replacing
mode", it is confirmed that the information recorded in
an information storage medium is precisely read out at
the stage immediately after recording. However, there
is a danger that the above described information cannot
be reproduced due to scratch or dust adhering to an
information storage medium, caused by the user's abuse.
In contrast, in the case where recording has been
carried out in the "2) multiplying mode", even if
information cannot be partially read in an information
storage medium due to a scratch or dust caused by
user's abuse or the like, because the same information
is backed up at another portion, the reliability of
information reproduction is remarkably improved. The
above backed up information is utilized for the
information which cannot be read at this time, and the
replacing process in "1) conventional replacing mode"
is carried out, thereby further improving reliability.
Therefore, there is attained advantageous effect that
high reliability of information reproduction after
recorded, considering countermeasures against scratch
or dust can be arranged by a processing operation in
"1) conventional replacing mode" alone and by using a
combination of the processing operation in "1)
conventional replacing mode" and a processing mode in
"2) multiplying mode". Methods for describing the
positional information on the above ECC block include:
a method for describing a physical sector number of a
physical sector which exists at a start position which
configures the above ECC block and a method for
describing an ECC block address, a physical segment
block address, or a data segment address. As described
later, in the present embodiment, a data area including
data of one ECC block size is referred to as a data
segment. A physical segment block is defined as a
physical unit on an information storage medium serving
as a location for recording data, and one physical
segment size coincides with a size of an area for
recording one data segment.
The present embodiment provides a mechanism
capable of recording the defect position information
detected in advance before the replacing process. In
this manner, the manufacturers of information storage
mediums check a defect state in the user data
additional writing range 204 immediately before
shipment. When the detected defect location is
recorded in advance (before the replacing process) or
the information recording/reproducing apparatus has
carried out an initializing process at the user's site,
the defect state in the user data additional writing
enable range 294 is checked so that the detected defect
location can be recorded in advance (before the
replacing process). In this way, the information
indicating a defect position detected in advance before
the replacing process corresponds to "information on
the presence or absence of the process for replacing a
defect block with a spare block" (SLR: State of Linear
Replacement) contained in the secondary defect list
entry information.
When the information SLR on the presence or
absence of the process for replacing a defect block
with a spare block is set to "0":
- The replacing process is carried out with
respect to a defect ECC block specified by "positional
information on replacement source ECC block"; and
Information, which can be reproduced, is recorded
in a location specified by "positional information on
replacement destination ECC block".
When the information SLR on the presence or
absence of the process for replacing a defect block
with a spare block is set to "1":
- A defect ECC block specified by "positional
information on replacement source ECC block" denotes a
defect block detected in advance at the state that
precedes the replacing process; and
A field of "positional information on replacement
destination ECC block" is blanked (no information is
recorded).
When a defect location is thus identified in
advance, there is attained advantageous effect that an
optimal replacing process can be carried out at a high
speed (and in a real time) at the stage at which an
information recording/reproducing apparatus carries out
additional writing in a write-once type information
storage medium. In addition, in the case where video
image information or the like is recorded in the
information storage medium, it is necessary to
guarantee continuity at the time of recording, and a
high speed replacing process based on the above
described information becomes important.
If a defect occurs in the user data additional
writing enable range 205, the replacing process is
carried out in predetermined location placed in the
spare area SPA or expanded spare area ESPA. Every time
the replacing process is carried out, one item of
Secondary Defect List Entry information is added; and
set information on the positional information on an ECC
block utilized as a substitute of the positional
information on a defect ECC block is recorded in this
RMD field 6. When additional writing of the user data
is newly repeated in the user data additional writing
enable range 205, if a new defect location is detected,
the replacing process is carried out, and the number of
items of the secondary defect list entry information
increases. A management information area (RMD field 6)
for defect management can be expanded by additionally
writing the recording management data RMD with an
increased number of items of this Secondary Defect List
Entry information into the reserved area 273 contained
in the recording management zone RMZ, as shown in
FIG. 36 (b). By using this method, the reliability of
defect management information itself can be improved
for the reasons described below.
1) The recording management data RMD can be
recorded while avoiding a defect location in the
recording management zone RMZ.
- A defect location may be produced in the
recording management zone RMZ shown in FIG. 36 (b).
The contents of the recording management data RMD newly
additionally written in the recording management zone
RMZ are verified immediately after additional writing,
thereby making it possible to sense a state in which
recording cannot be carried out due to a defect. In
that case, the recording management data RMD is
rewritten adjacent to the defect location, thereby
making it possible to record the recording management
data RMD in the form such that high reliability is
guaranteed.
2) Even if the past recording management data RMD
cannot be reproduced due to the scratch adhering to an
information storage medium surface, a certain degree of
backup can be carried out.
- For example, in the case where the example shown
in FIG. 36 (b) is taken, a state in which, after
recording management data RMD#2 has been recorded, the
information storage medium surface is scratched due to
the user's mistake or the like, and then, the recording
management data RMD#2 cannot be reproduced, is presumed
as an example. In this case, a certain degree of the
past defect management information (information
contained in the RMD field 6) can be recovered by
reproducing information on the recording management
data RMD#1 instead.
Size information on the RMD field 6 is recorded at
the beginning of the RMD field 6, and this field size
is made variable, thereby making it possible to expand
the management information area (RMD field 6) for
defect management. Each RMD field is set to 2048 size
(for one physical sector size), as described
previously. However, if a plenty of defects occur with
the information storage medium, and then, the replacing
process count increases, the size of the Secondary
Detect List information increases, and the 2048 byte
size (for one physical sector size) becomes
insufficient. In consideration of this situation, the
RMD field 6 can be set to a plurality of multiples of
2048 size (recording across a plurality of sectors can
be carried out). Namely, if "the size of the RMD field
6" has exceeded 2048 bytes, an area for a plurality of
physical sectors is arranged to the RMD field 6.
The secondary defect list information SDL records:
the secondary defect list entry information described
above; "secondary defect list identification
information" indicating a start position of the
secondary defect list information SDL; and "secondary
defect list update counter (update count information)"
indicating count information as to how many times the
secondary defect list information SDL has been
rewritten. The data size of the whole secondary defect
list information SDL can be identified based on "number
information on the secondary defect list entry".
As described previously, user data recording is
locally carried out in units of R zone in the user data
additional writing enable range 205. That is, part of
the user data additional writing enable range 205
reserved for receding the user data is referred to as
an R zone. This R zone is divided into two types
according to a recording condition. Among them, a type
of zone in which additional user data can be further
recorded is referred to as an Open R Zone, and a type
of zone in which no further user data can be added is
referred to as a Complete R Zone. The user data
additionally writing enable range 205 cannot have three
or more Open R zones. That is, up to two Open R zones
can be set in the user data additional writing enable
range 205. A location in which either of the above
two types of R zones are not set in the user data
additional writing enable range 205, i.e., a location
in which the user data is reserved to record the user
data (as either of the above two types of R zones), is
referred to as an unspecified R zone (Invisible R
Zone). In the case where the user data is fully
recorded in the user data additional writing enable
range 205, and then, no data can be added, this
Invisible R zone does not exist. Up to 254-th R zone
position information is recorded in an RMD field 7.
The "whole R zone number information" first recorded in
the RMD field 7 denotes a total number totalizing the
number of Invisible R Zone logically established in the
user data additional writing enable range 205, Open R
Zones and the number of Complete R Zones. Next, the
number information on the first Open R zone and the
number information on the second Open R zones are
recorded. As described previously, the user data
additional writing enable range 205 cannot have three
or more Open R zones, and thus, "1" or "0" is recorded
(in the case where the first or second Open R zone does
not exist). Next, the start position information and
the end position information on the first Complete R
zone are described in physical sector numbers. Then,
the second to 254th start position information and end
position information are sequentially described in the
physical sector numbers.
In an RMD field 8 and subsequent, the 255-th and
subsequent start position information and end position
information are sequentially described in the physical
sector numbers, and a maximum of RMD fields 15 (a
maximum of 2047 Complete R zones) can be described
according to the number of Complete R Zones.
FIGS. 51 and 52 each show another embodiment with
respect to a data structure in the recording management
data RMD shown in FIGS. 44 to 49.
In the embodiment shown in FIGS. 51 and 52, up to
128 bordered areas BRDAs can be set on one write-once
type information storage medium. Therefore, the start
position information on the first to 128 border out
areas BRDOs is recorded in the RMD field 3. In the
case where (128 or less) bordered areas BRDAs are set
midway, "OOh" is set as the start position information
on the subsequent border out areas BRDOs. In this
manner, it is possible to identify how many bordered
areas BRDAs are set on the write-once information
storage medium merely by checking to where the start
position information on the border out areas BRDOs are
recorded in the RMD field 3.
In the embodiment shown in FIGS. 51 and 52, up to
128 expanded recording management zones RMZs can be set
on one write-once information storage medium. As
described above, there are two types of expanded
recording management zones RMZs such as:
1) an expanded recording management zone RMZ set
in the border-in area BRDI; and
2) an expanded recording management zone RMZ set
by utilizing an R zone.
In the embodiment shown in FIGS. 51 and 52,
without discriminating these two types of RMZ zones,
they are managed by receding a pair of the start
position information on the expanded recording
management zone RMZ (indicated by the physical sector
number) and size information (number information on
occupying physical sectors) in the RMD field 3. In the
embodiment shown in FIGS. 51 and 52, although there has
been recorded: information on a pair of the start
position information (indicated by the physical sector
number) and size information (number information on
occupying physical sectors) on the expanded recording
management zone RMZ, a set of the start position
(indicated by the physical sector number) and the end
position information (indicated by the physical sector
number) on the expanded recording management zone RMZ
may be recorded without being limited thereto. In the
embodiment shown in FIGS. 51 and 52, although the
expanded recording management zones RMZ numbers have
been assigned in order set on the write-once type
information storage medium, the expanded recording
management data zone RMZ numbers can be assigned in
order from the lowest physical sector number as a start
position without being limited thereto. Then, the
latest recording management data RMD is recorded, a
currently used recording management zone (which is open
to enable additional writing of RMD) is specified by
the number of this expanded recording management zone
RMZ. Therefore, the information recording/reproducing
apparatus or the information reproducing apparatus
identifies the start position information on the
currently used (opened so that the RMZ can be
additionally recorded) recording management zone based
on these items of information, and carries out
identification of which one is the latest recording
management data RMD from the identified information.
Even if the expanded recording management zone is
arranged to be distributed onto the write-once type
information storage medium, the information
recording/reproducing apparatus or information
reproducing apparatus can easily carry out
identification of which one is the latest recording
management data RMD by taking a data structure shown in
FIGS. 51 and 52 each. Based on these items of
information; the start position information on the
currently used (opened) recording management zone is
identified; and the location is accessed to identify to
where the recording management data RMD has already
been recorded. In this manner, the information
recording/reproducing apparatus or the information
reproducing apparatus can easily identify to where the
updated latest recording management data may be
recorded.
In the case where 2) an expanded recording
management zone RMZ set by utilizing an R zone has been
set, one whole R zone corresponds to one expanded
recording management zone RMZ. Thus, the physical
sector number indicating the corresponding start
position of the expanded recording management zone RMZ
described in the RMD field 3 coincides with the
corresponding physical sector number indicating the
start position of the R zone described in the RMD
fields 4 to 21.
In the embodiment shown in FIGS. 51 and 52, up to
4606 (4351 + 255) R zones can be set in one write-once
type information storage medium. This set R zone
position information is recorded in the RMD field 4 to
21. The start position information on each R zone is
displayed by the information on the physical sector
number, and the physical sector numbers LRAs (Last
Recorded Addresses) indicating the end recording
position in each R zone are recorded in pair. Although
the R zones described in the recording management data
RMD are set in order of setting R zones in the
embodiment shown in FIGS. 51 and 52, these zones can be
set in order from the lowest physical sector number
indicating the start position information without being
limited thereto. In the case where R zone setting of
the corresponding number is not provided, "OOh" is
recorded in this field. Number information on
invisible R zone is described in the RMD field 4. This
number information on invisible R zone is indicated by
a total number of the number of invisible R zones
(zones in which area reserved for data recording is not
made in data area DTA); the number of open type R zones
(zones each having an unrecorded area in which
additional writing can be carried out); and the number
of complete type R zones (R zones which are already
complete and which does not have an unrecorded area in
which additional writing can be carried out). In the
embodiment shown in FIGS. 51 and 52, it is possible to
set up to two Open R zones in which additional writing
can be carried out. In this way, by setting up to two
Open R zones, it is possible to record video image
information or audio information for which continuous
recording or continuous reproduction must be guaranteed
in one Open R zone, and then, separately record
management information relevant to the video image
information or audio information; general information
used by a personal computer or the like; or file system
management information in the remaining one Open R
zone. Namely, it is possible to separately record
plural items of information in another Open R zone
according to type of user data to be recorded. This
results in improved convenience in recording or
reproducing AV information (video image information or
audio information). In the embodiment shown in
FIGS. 51 and 52, which R zone is an Open R zone is
specified by the R zone allocation numbers arranged in
the RMD fields 4 to 21. That is, the R zones are
specified by the corresponding R zone number to the
first and second Open R zones. A search can be easily
made for the Open R zone by taking such a data
structure. In the case where no Open R zone exists,
"OOh" is recorded in that field. In the present
embodiment, the end position of an R zone coincides
with the end recording position in the Complete R zone,
the end position of the R zone and the last recording
position LRA in the R zone are different from each
other in the Open T zone. On the way of additionally
writing user information in the Open R zone (at a state
that precedes completion of additional writing of the
recording management data RMD to be updated), the end
recording position and a recording position at which
additional writing can be further carried out are
shifted. However, after an additional writing process
of user information has completed, after completing the
additional writing process of the latest recording
management data RMD to be recorded, the end recording
position and an end recording position at which
additional writing can be further carried out coincide
with each other. Therefore, after completing the
additional writing process of the latest recording
management data RMD to be updated, in the case where
additional writing of new user data is carried out, the
control unit 143 in the information
recording/reproducing apparatus shown in FIG. 11
carries out processing in accordance with procedures
for:
1) checking a number of an R zone which
corresponds to the Open R zone described in the RMD
field 4;
2) checking a physical sector number indicating an
end recording position in the Open R zone described in
each of the RMD fields 4 to 21 to identify an end
recording position at which additional writing can be
carried out; and
3) starting additional writing from the above
identified end recording position NWA at which
additional writing can be carried out.
In this manner, a new additional writing start
position is identified by utilizing Open R zone
information in the RMD field 4, thereby making it
possible to sample a new additional writing start
position simply and speedily.
FIG. 53 shows a data structure in an RMD field in
the embodiment shown in FIGS. 51 and 52. As compared
with the embodiment shown in FIGS. 44 to 49, there are
added: address information on a location in which
recording condition adjustment has been made in the
inner drive test zone DRTZ (which belongs to the data
lead-in area DTLDI); and address information on a
location in which recording condition adjustment has
been made in the outer drive test zone DRTZ (which
belongs to the data lead-out area DTLDO). These items
of information are described in the physical segment
block address numbers. Further, in the embodiment
shown in FIG. 53, there are added: information relating
to a method for automatically adjusting a recording
condition (running OPC); and the end DSV (Digital Sum
Value) value at the end of recording.
FIG. 56 shows an outline of converting procedures
for, after an ECC block is configured of a data frame
structure in which user data in units of 2048 bytes has
been recorded, and then, sync codes have been added,
forming a physical sector structure to be recorded in
an information storage medium. These converting
procedures are employed in common for a read-only type
information storage medium, a write-once type
information storage medium, and a rewritable-type
information storage medium. According to each
converting stage, a data frame, a scrambled frame, a
recording flame, or recorded data field are defined.
The data frame is a location in which user data is
recorded. This frame is composed of: main data
consisting of 2048 types; a four-type data ID; a
two-byte ID error detecting code (IED); a six-byte
reserved bytes (RSV); and a four-byte error detecting
code (EDC). First, after an IED (ID error detecting
code) has been added to a data ID described later, the
6-byte reserved byte and main data consisting of
2048 bytes and in which the user data is recorded are
added. Then, an error detecting code (EDC) is added.
Then, scrambling relevant to the main data is executed.
Here, a Cross Reed-Solomon Error Correction Code is
applied to these scrambled 32 data frames (scrambled
frames), and an ECC encode processing operation is
executed. In this manner, a recording frame is
configured. This recording frame includes a parity of
outer-code (PO) and a parity of inner-code (PI). The
PO and PI each are error correcting codes produced with
respect ECC blocks, each of which is formed of 32
scrambled frames. The recording frame, as described
previously, is subjected to ETM (Eight to Twelve
Modulation) for converting eight data bits to 12-
channel bits. Then, a sync code SYNC is added to the
beginning on a 91 by 91 bytes basis, and 32 physical
sectors are formed. As described in the lower right
frame shown in FIG. 56, the present embodiment is
featured in that one error correcting unit (ECC block)
is composed of 32 sectors. As described later, the
numbers "0" to 31" in each frame shown in FIG. 60 or 61
indicate the numbers of physical sectors, respectively,
and a structure is provided to ensure that one large
ECC block is composed of a total of 32 physical
sectors. In a next-generation DVD, even in the case
where a scratch whose extent is identical to that of a
current-generation DVD adheres to an information
storage medium surface, it is required to enable
reproduction of precise information by an error
correction processing operation. In the present
embodiment, recording density has been improved for the
achievement of high capacity. As a result, in the case
where a conventional one ECC block = 16 sectors, a
length of a physical scratch which can be corrected by
error correction is reduced as compared with a
conventional DVD. As in the present embodiment, there
is attained advantageous effect that one ECC block is
composed of 32 sectors, thereby making it possible to
increase an allowable length of a scratch on the
information storage medium surface for which error
correction can be carried out and to ensure
compatibility/format continuity of a current DVD ECC
block structure.
FIG. 57 shows a structure in a data frame. One
data frame is 2064 bytes consisting of 172 bytes x 2 x
6 rows, and includes main data of 2048 bytes. IED is
an acronym for IE Error Detection Code, and denotes a
reserved area for enabling setting of information in
the future. EDC is an acronym for Error Detection
Code, and denotes an additional code for error
detection of a whole data frame.
FIG. 50 shows a data structure in a data ID shown
in FIG. 57. The data ID is composed of items of
information on data frames 921 and 922. The data frame
number indicates a physical sector number 922 of the
corresponding data frame.
The data frame information 921 is composed of the
following items of information.
- Format type 931
... Ob: This indicates CLV
Ib: This indicates zone configuration
- Tracking method 932
... Ob: This is pit-compatible and uses a
DPD (Differential Phase Detect) technique in the
present embodiment
Ib: This is pre-groove compatible and
uses a push-pull technique or a DPP (Differential Push-
Pull) technique.
- Recording film reflection factor 933
... Ob: 40% or more
Ib: 40% or less
- Recording type information 934
... Ob: General data
Ib: Real time data (Audio Video data)
- Area type information 935
... OOb: Data area DTA
Olb: System lead-in area SYLDI or data
lead-in area DTLDI
lOb: Data lead-out area DTLDO or system
lead-out area SYLDO
- Data type information 936
... Ob: Read-only data
Ib: Rewritable data
- Layer number 937
... Ob: Layer 0
Ib: Layer 1
FIG. 58A shows an example of default values
assigned to a feedback shift register when a frame
after scrambled is produced. FIG. 58B shows a circuit
configuration of the feedback shift register for
producing scrambled bytes. The values of r7 (MSB) to
rO (LSB) are used as scramble bytes while they are
shifted by 8 by 8 bit basis. As shown in FIG. 58A,
16 types of preset values are provided in the present
embodiment. The default preset numbers shown in
FIG. 58A are equal to 4 bits of data ID (b7 (MSB) to b4
(LSB)). When data frame scrambling is started, the
default values of r!4 to rO must be set to the default
preset values in a table shown in FIG. 58A. The same
default preset value is used for 16 continuous data
frames. Next, the default preset values are changed,
and the changed same preset value is used for the 16
continuous data frames.
The least significant eight bits of the default
values of r7 to rO are sampled as a scramble byte SO.
Then, eight-bit shifting is carried out, and the
scrambled byte is then sampled. Such an operation is
repeated 2047 times.
FIG. 59 shows an ECC block structure in the
present embodiment. The ECC block is formed of 32
scrambled frames. 192 rows + 16 rows are arranged in a
vertical direction, and (172 + 10) x 2 columns are
arranged in a horizontal direction. BQ,Q, B]_,Q, ...
are one byte, respectively. PO and PI are error
correction codes, and an outer parity and an inner
parity. In the present embodiment, an ECC block
structure using a multiple code is configured. That
is, as error correction additional bits, a structure is
provided such that, PI (Parity in) is added in a "row"
direction, and PO (Parity out) is added in a "column"
direction. A high error correction capability using an
erasure correction and a vertical and horizontal
repetitive correction process can be guaranteed by
configuring such an ECC block structure using a
multiple code. Unlike a conventional DVD ECC block
structure, the ECC block structure shown in FIG. 59 is
featured in that two Pis are set in the same "row".
That is, PI of 10-byte size described at the center in
FIG. 59 is added to 172 bytes arranged at the left
side. That is, for example, 10-byte PI from BQ o to
BO 172 is added to 172-byte data from BQ g to BQ 171/
and 10-byte PI from 61,172 to Bl 181 i-s added to
172-byte data from B]_ Q to Bl,171- The PI of 10-byte
size described at the right end of FIG. 59 is added to
172 bytes arranged at the center on the left side of
the figure 59. That is, for example, 10-byte PI from
Eg 354 to BQ 363 are added to 172-byte data from &QriQ2
to B0,353-
FIG. 60 shows an illustration of a frame
arrangement after scrambled. Units of (6 rows x
172 bytes) are handled as one frame after scrambled.
That is, one ECC block is formed of 32 frames after
scrambled. Further, this system handles a pair of
(block 182 bytes x 207 bytes). When L is assigned to
the number of each frame after scrambled, in the left
side ECC block, and R is assigned to the number of each
frame after scrambled in the right side ECC block, the
frames after scrambled are arranged as shown in
FIG. 60. That is, the left and right frames after
scrambled exist alternately at the left side block, and
the frames after scrambled exist alternately at the
right side block.
That is, the ECC block is formed of 32 frames
after continuously scrambled. Lines of the left half
of odd numbered sectors each are exchanged with those
of the right half. 172 x 2 bytes x 192 rows are equal
to 172 bytes x 12 rows x 32 scrambled frames, and are
obtained as a data area. 16-byte PO is added to form
an outer code of RS (208, 192, 17) in each 172 x
2 columns. 10-byte PI (RS (182, 172, 11)) is added to
each 208 x 2 rows in the left and right blocks. PI is
added to a row of PO as well. The numerals in frames
indicate scrambled frame numbers, and suffixes R and L
denote the right half and the left half of the
scrambled frame. The present embodiment is featured in
that the same data frame is arranged to be distributed
in a plurality of small ECC blocks. Specifically, in
the present embodiment, a large one ECC block is
composed of two small ECC blocks, and the same data
frame are arranged to be alternately distributed into
two small ECC blocks. As has already been described in
FIG. 59, PI of 10-byte size described at the center is
added to 172 bytes arranged at the left side, and PI of
10 byte size described on the right end is added to
172 bytes arranged at the center on the left side.
Namely, the left side small ECC block is composed of
continuous PI of 10 bytes from the left end of FIG. 59,
and the right side small ECC block is composed of
10 bytes at the right end from the central 172 bytes.
The signs in each frame are set in response to these
blocks in FIG. 60. For example, "2-R" denotes which of
a data frame number and the left and right small ECC
blocks one belongs to (for example, one belongs to
right side small ECC block in second data frame). As
described later, with respect to each of the finally
configured physical sectors, the data contained in the
same physical sector is also alternately arranged to be
distributed into the left and right small ECC blocks
(the columns of the left half in FIG. 61 are included
in the left side small ECC block (small ECC block "A"
on the left side shown in FIG. 64), and the column of
the right half are included in small ECC blocks (small
ECC block B on the right side shown in FIG. 64).
Thus, when the same data frame is arranged to be
distributed in a plurality of small ECC blocks, the
reliability of recording data is improved by improving
an error correction capability of the data contained in
a physical sector (FIG. 61). For example, let us
consider a case in which a track fails at the time of
recording; the recorded data is overwritten; and data
for one physical sector is damaged. In the present
embodiment, the damaged data contained in one sector is
subjected to error correction by using two small ECC
blocks; a burden on error correction in one ECC block
is reduced; and error correction with better
performance is guaranteed. In the present embodiment,
even after forming an ECC block, a structure is
provided such that a data ID is arranged at the start
position of each sector, thus making it possible to
check a data position at the time of access at a high
speed.
FIG. 61 shows an illustration of a PO interleaving
method. As shown in FIG. 61, 16 parities are
distributed on one by one row basis. That is,
16 parity rows are arranged on a one by one row basis
with respect to two recording frames placed.
Therefore, a recording fame consisting of 12 rows is
obtained as 12 rows + 1 row. After this row
interleaving has been carried out, 13 rows x 182 bytes
are referred to as a recording frame. Therefore, an
ECC block after row interleaved is formed of 32
recording frames. In one recording, as described in
FIG. 60, 6 rows exist in each of the right side and
left side blocks. POs are arranged so as to be
positioned in different rows between a left block (182
x 208 bytes) and a right block (182 x 208 bytes).
FIG. 61 shows one complete type ECC block. However, at
the time of actual data reproduction, such ECC blocks
continuously arrive at an error correction processing
section. In order to improve such an error correction
processing capability, there is employed an
interleaving system as shown in FIG. 61.
Referring to FIG. 61, a detailed description will
be given with respect to a relationship from a
structure in one data frame shown in FIG. 57 to a PO
interleaving method shown in FIG. 61. FIG. 64 is an
enlarged view showing, an upper side portion of an EC
block structure after PO-interleaved shown in FIG. 61,
wherein allocation locations of data ID, IED, RSV, and
EDC shown in FIG. 57 are explicitly indicated, thereby
visually identifying a series of conversion from
FIGS. 57 to 61. "0-L" "0-R", "1-R", and "1-L" shown in
FIG. 64 correspond to "0-L", "0-R", "1-R", and "1-L"
shown in FIG. 60, respectively. The "0-L" and "1-L"
denote data obtained after only the main data has been
scrambled with respect to the left half shown in
FIG. 57, that is, a set composed of 172 bytes and six
rows from the center line to the left side. Similarly,
the "0-R" and "1-R" denote data obtained after only the
main data has been scrambled with respect to the right
half shown in FIG. 57, that is, a set composed of 172
bytes and six rows from the center line to the right
side. Therefore, as is evident from FIG. 57, data ID,
IED, and RSV are arranged in order from the beginning
of the first row (row 0) to byte 12 of "0-L" and "1-L".
In FIG. 64, the centerline to the left side configures
the left side small ECC block "A", and the centerline
to the right side configures the right side small ECC
block "B". Therefore, as is evident from FIG. 64, data
ID#1, data ID#2, IED#0, IED#2, RSV#0, and RSV#2
included in "0-L" and "2-L" are included in the left
side small ECC block "A". In FIG. 60, "0-L" and "2-L"
are arranged at the left side, and "0-R" and "2-E" are
arranged at the right side. In contrast, "1-R" and
"1-L" are arranged at the left and right sides,
respectively. Data ID#1, IED#1, and RSV#1 are arranged
from the beginning to byte 12 of the first row in
"1-L". Thus, as a result of reversing the left and
right allocations, as is evident from FIG. 64, data
ID#1, IED#1, and RSV#1 included in "1-L" is configured
in the right side small ECC block "B". In the present
embodiment, a combination of "0-L" and "0-R" in FIG. 64
is referred to as a "0-th recording frame" and a
combination of "1-L" and "1-R" is referred to as a
"first recording frame". The boundary between the
recording frames are indicated by the bold characters
shown in FIG. 64. As is evident from FIG. 64, data ID
is arranged at the beginning of each recording frame
and PO and PI-L are arranged at the end of each
recording frame. As shown in FIG. 64, the present
embodiment is featured in that small ECC blocks in
which data ID is included are different from each other
depending on the odd-numbered and even-numbered
recording frames, and data ID, IED, and RSV are
alternately arranged in the left side and right side
small ECC blocks "A" and "B" in accordance with
continuous recording frames. The error correction
capability in one small ECC lock is limited, and error
correction is disabled with respect to a random error
exceeding a specific number or a burst error exceeding
a specific length. As described above, data ID, IED,
and RSV are alternately arranged in the left side and
right side small ECC blocks "A" and "B", thereby making
it possible to improve the reliability of reproduction
of data ID. That is, even if a defect on an
information storage medium frequently occurs, disabling
error correction of any of the small ECC blocks and
disabling decoding of data ID to which the faulty block
belongs, data ID, IED, and RSV are alternately arranged
in the left side and right side small ECC blocks "A"
and "B", thus enabling error correction in the other
small ECC block and enabling decoding the remaining
data ID. Because the address information contained in
data ID continuously lasts, the information on data ID
is used, enabling interpolation with respect to the
information on data ID which has not been successfully
decoded. As a result, the access reliability can be
improved according to the embodiment shown in FIG. 64.
The numbers parenthesized at the left side of FIG. 64
denote row numbers in an ECC block after POinterleaved.
In the case where numbers are recorded in
an information storage medium, row numbers are
sequentially recorded from the left to the right. In
FIG. 64, data ID intervals included in each recording
frame are always constantly arranged, and thus, there
is attained advantageous effect that data ID position
searching capability is improved.
A physical sector structure is shown in FIGS. 62A
and 62B. FIG. 62A shows an even numbered physical
sector structure, and FIG. 62B show an odd numbered
data structure. In FIGS. 62A and 62B, with respect to
both of an even recorded data field and an odd recorded
data field, outer parity PO information shown in
FIG. 61 is inserted into a sync data area contained in
the last 2 sync frames (i.e., in a portion at which the
last sync code is SYS and a portion at which the
immediately succeeding sync data and sync code is SY1;
and a portion at which sync code is SYl and a portion
at which the immediately succeeding sync data is
arranged in the sync data area shown in FIG. 61 wherein
information of outer parity PO is inserted).
Part of the left side PO shown in FIG. 60 is
inserted at the last two sync frames in the even
recorded data field, and part of the right side PO
shown in FIG. 60 is inserted at the last two sync
frames in the odd recorded data field. As shown in
FIG. 60, one ECC block is composed of the left and
right small ECC blocks, respectively, and the data on
PO groups alternately different depending on sectors
(the data on PO belonging to left small ECC block or
the data on PO belonging to right small ECC block) is
inserted. The even numbered physical sector structure
shown in FIG. 62A and the odd numbered data structure
shown in FIG. 62B are divided into two sections at a
center line. The left side "24 + 1092 + 24 + 1092
channel bits are included in the left side small ECC
block shown in FIG. 59 or 60, and the right side "24 +
1092 + 24 + 1092 channel bits are included in the right
side small ECC block shown in FIG. 59 or 60. In the
case where the physical sector structure shown in
FIGS. 62A and 62B is recorded in an information storage
medium, this structure is serially recorded on one by
one column base. Therefore, for example, in the case
where channel bit data on an even numbered physical
sector structure shown in FIG. 62A is recorded in an
information storage medium, the data on 2232 channel
bits first recorded is included in the left side small
ECC block, and the data on the 2232 channel bits
recorded next is included in the right side small EC
block. Further, the data on 2232 channel bits recorded
next is included in the left side small ECC block. In
contrast, in the case where the channel bit data on an
odd numbered data structure shown in FIG. 62B is
recorded in an information storage medium, the data on
2232 channel bits first recorded is included in the
right side small ECC block, and the data on the 2232
channel bits recorded next is included in the left side
small EC block. Further, the data on 2232 channel bits
recorded next is included in the right side small ECC
block. Thus, the present embodiment is featured in
that the same physical sector is alternately included
in two small ECC blocks on a 2232 by 2322 channel bit
basis. In other words, a physical sector is formed in
the shape such that the data included in the right side
small ECC block and included in the left side small ECC
block are alternately arranged to be distributed on a
2232 by 2332 channel bit basis, and the formed physical
sector is recorded in an information storage medium.
As a result, there is attained advantageous effect that
a structure strong to a burst error can be provided.
For example, let us consider a state in which a
lengthwise scratch occurs in a circumferential
direction of an information storage medium, and there
occurs a burst error which disables decoding of data
exceeding 172 bytes. In this case, a burst error
exceeding 172 bytes is arranged to be distributed in
two small ECC blocks. Thus, a burden on error
correction in one ECC block is reduced, and error
correction with better performance is guaranteed.
The present embodiment is featured by, as shown in
FIGS. 62A and 62B, a data structure in a physical
sector is different from another depending on whether
or not the physical sector number of a physical sector
configuring one ECC block is an even number or an odd
number. Namely,
1) Small ECC blocks (right side or left side) to
which the first 2232 channel bit data of a physical
sector belongs are different from each other; and
2) There is provided a structure in which data on
a PO group alternately different from each other
depending on sectors is inserted.
As a result, in order to guarantee a structure in
which data ID is arranged at the start position of all
the physical sectors even after an ECC block has been
configured, a data position check at the time of access
can be made at a high speed. In addition, POs which
belong to different small ECC blocks are mixed and
inserted into the same physical sector, structurally
simplifying a method employing a PO inserting method as
shown in FIG. 61, facilitating information sampling on
a sector by sector manner after error correction
processing in an information reproducing apparatus; and
simplifying an ECC block data assembling process in an
information recording/reproducing apparatus.
In a method for specifically achieving the above
contents, PO interleaving and inserting positions have
different structures depending on the left and right.
Portions indicated by the narrow double lines shown in
FIG. 61 or portions indicated by the narrow double line
and shading indicate the PO interleaving and inserting
positions. PO is inserted at the left end in an even
numbered physical sector number or at the right end in
an odd numbered physical sector number. By employing
this structure, even after an ECC block has configured,
data ID is arranged at the start position of a physical
sector, thus making it possible to check a data
position at the time of access at high speed.
FIG. 63 shows an embodiment of specific pattern
contents from sync codes "SYO" to "SYS" shown in
FIGS. 62A and 62B. Three states from State 0 to State
2 are provided in accordance with a modulation rule
according to the present embodiment (a detailed
description will be given later). Four sync codes from
SYO to SYS are set, and each code is selected from the
left and right groups shown in FIG. 63 according to
each state. In a current DVD specification, as a
modulation system, there employed RLL(2, 10) of 8/16
modulation (8 bits are converted to 16 channel bits (a
minimum value is 2 and a maximum value is 10 when Run
Length Limit: d = 2, k = 10: "0" continuously lasts),
four states from State 1 to State 4, i.e., eight types
of sync codes from SYO to SY7 are set. In comparison,
in the present embodiment, types of sync codes are
decreased. In an information recording/reproducing
apparatus or an information reproducing apparatus, at
the time of information reproduction from an
information storage medium, types of sync code is
identified in accordance with a pattern matching
technique. As in the present embodiment, by
significantly decreasing types of sync codes, target
patterns required for matching are decreased in number;
a processing operation required for pattern matching is
simplified; and the processing efficiency is improved,
making it possible to improve a recognition speed.
In FIG. 63, a bit (channel bit) indicated by "#"
denotes a DSV (Digital Sum Value) control bit. As
described later, the above DSV control bit is
determined so as to suppress a DC component by means of
a DSV controller (so as to make a value of DSM close to
0). The present embodiment is also featured in that a
polarity inversion channel bit "#" is included in a
sync code. There is attained advantageous effect that
a value of "#" can be selected as "1" or "0" so that
the DSV value is close to "0" in a macroscopic point of
view, including both frame data fields (1092 channel
bit fields shown in FIGS. 62A and 62B) sandwiching the
above sync code, enabling DSV control from the
macroscopic point of view.
As shown in FIG. 63, the sync codes in the present
embodiment is composed of the sections below.
1) Sync position detecting code section
This section has a common pattern in all sync
codes, and forms a fixed code area. A sync code
allocation position can be detected by detecting this
code. Specifically, this section denotes the last 18

channel bits "010000 000000 001001" in each sync code
in FIG. 63.
2) Modulation conversion table selector code
section
This section forms part of a variable code area,
and changes in response to state number at the time of
modulation. The first channel bit shown in FIG. 63
corresponds to this section. That is, in the case
where one of State 1 and State 2 is selected, the first
channel bit is set to "1" in any of the codes from SYO
to SYY3. When State 0 is selected, the first channel
bit of a sync code is set to "1". However, as an
exception, the first channel bit of SY3 in State 0 is
set to "0".
3) Sync frame position identification code section
Part of a variable code area is composed of codes
identifying types from SYO to SY3 in sync codes. The
first to sixth channel bit section in each sync code
shown in FIG. 63 corresponds to this section. As
described later, a relative position in the same sector
can be detected from a connection pattern of three by
three sync codes continuously detected.
4) DC suppressing polarity inversion code section
A channel bit at a position "#" shown in FIG. 63
corresponds to this section. As described above, this
bit is inverted or non-inverted, thereby making close
to "0" the DSV value of a channel bit pattern including
the preceding and succeeding frame data.
In the present embodiment, 8/12 modulation (ETM:
Eight to Twelve Modulation), RLL (1, 10) is employed as
a modulation method. That is, eight bits are converted
to 12-cahnnel bits at the time of modulation, and a
minimum value (d value) is set to 1, and a maximum
value (k value) is set to 10 in a range such that the
settings "0" after converted are continuous. In the
present embodiment, although high density can be
achieved more significantly than conventionally by
setting d = 1, it is difficult to obtain a sufficiently
large reproduction signal amplitude at a site indicated
by the mark indicating the highest density.
Therefore, as shown in FIG. 11, an information
recording/reproducing apparatus according to the
present embodiment has the PR equalizing circuit 130
and the Viterbi decoder 156, and enables very stable
signal reproduction by using a PRML (Partial Response
Maximum Likelihood) technique. In addition, k = 10 is
set, and thus, there is no case in which eleven or more
"0" settings are continuous in the modulated general
channel bit data. By utilizing this modulation rule,
the above sync position detecting code section has a
pattern which hardly appears in the modulated general
channel bit data. That is, as shown in FIG. 63, in the
sync position detecting code section, 12 (= k + 2) "0"s
are continuously arranged. The information
recording/reproducing apparatus or the information
reproducing apparatus finds this section and detects a
position of the sync position detecting code section.
In addition, if "0" continuously lasts too much, a bit
shift error is likely to occur. Thus, in order to
reduce this problem, in the sync position detecting
code section, a pattern having less continuous "0"s is
arranged immediately after that portion. In the
present embodiment, d = 1, and thus, it is possible to
set "101" as the corresponding pattern. However, as
described above, a sufficiently large reproduction
signal amplitude is hardly obtained at a site of "101"
(at a site indicating the highest density), and thus,
"1001" is arranged instead, obtaining a pattern of the
sync position detecting code section as shown in
FIG. 63.
The present embodiment is featured in that, as
shown in FIG. 63, 18 channel bits at the back side in a
sync code are independently used as (1) sync position
detecting code section, and the front side 6 channel
bits are used as (2) modulation conversion table
selector code section; (3) sync frame position
identification code section; or (4) DC suppression
polarity inversion code section. There is attained
advantageous effect that in the sync codes, the sync
position detecting code section in item (1) is provided
independently, thereby facilitating single detection
and enhancing sync position detecting precision; the
code sections in items (2) to (4) are used in common in
the 6-channel bits, thereby reducing the data size of
the whole sync codes (channel bit size); and a sync
data occupying rate is increased, thereby improving
substantial data efficiency.
The present embodiment is featured in that, from
among four types of sync codes shown in FIG. 63, only
SYO is arranged at the first sync frame position in a
sector, as shown in FIGS. 62A and 62B. Advantageous
effect thereof includes that the start position in a
sector can be identified immediately merely by
detecting SYO, and the start position sampling process
in the sector is extremely simplified.
The present embodiment is also featured in that
all of the combination patterns of three continuous
sync codes are different from each other in the same
sector.
A detailed description will be given with respect
to the pattern contents of a reference code recorded in
the reference code recording zone RCZ shown in
FIGS. 35A to 35C. In a current DVD, an "8/16
modulation" system for converting 8-bit data to 16-
channel bits is employed as a modulation system. As a
pattern of a reference code serving as a channel bit
pattern recorded in an information storage medium after
modulated, there is employed a repetition pattern
"00100000100000010010000010000001". In comparison with
this pattern, in the present embodiment, ETM modulation
for modulating 8-bit data into 12-channel bits is used
as shown in FIGS. 32 to 34, providing an RLL (1, 10)
5 run length restriction. In addition, the PRML
technique is employed for signal reproduction from the
data lead-in area DTLDI, data area DTA, data lead-out
area DTLDO, and middle area MDA. Therefore, there is a
need for setting the above described modulation rule
10 and a pattern of a reference code optimal for PRML
detection. In accordance with the RLL(1, 10) run
length restriction, a minimum value of continuous "0"
settings is "d = 1", and is a repetition pattern of
"10101010". Assuming that a distance from a code "0"
15 to the next adjacent code is "T", a distance relevant
to the adjacent "1" in the above pattern is obtained as
"2T". In the present embodiment, in order to achieve
high density of an information storage medium, as
described previously, a reproduction signal from the
20 repetition pattern ("10101010") of "2T" recorded on the
information storage medium is close to a shutdown
frequency of MTF (Modulation Transfer Function)
characteristics of an objective lens in an optical head
(exists in the information recording/reproducing unit
25 141 shown in FIG. 11); and thus, a degree of modulation
(signal amplitude) is hardly obtained. Therefore, in
the case where a reproduction signal from a repetition
pattern ("10101010") of "2T" has been used as a
reproduction signal used for circuit tuning of the
information reproducing apparatus or the information
recording/reproducing apparatus (for example,
5 initialing and optimizing tap coefficients in the tap
controller 332 shown in FIG. 15), noise effect is
significant, and stabilization is poor. Therefore,
with respect to a signal after modulated in accordance
with RLL(1, 10) run length restriction, then, it is
10 desirable to carry out circuit tuning by using a
pattern of "3T" having high density. In the case where
a digital sum value (DSV) of the reproduction signal is
considered, an absolute value of a DC (direct current)
value increases in proportion to the number of
15 continuous "0"s between "1" and next "1" that
immediately follows it, and the increased value is
added to the immediately preceding DSV value. The
polarity of this added DC value is inverted every time
"1" is reached. Therefore, as a method for setting the
20 DSV value to "0" where a channel bit pattern having
continuous reference code is followed, the DSV value is
set to be "0" in 12 channel bit patterns after ETMmodulated,
whereby the degree of freedom in reference
code pattern design is increased more significantly by
25 setting to an odd number the number of generated "1"
appearing in 12 channel bit patterns after ETMmodulated;
offsetting a DC component generated in one
set of reference code cells consisting of a next set.
Therefore, in the present embodiment, the number of "1"
appearing in the reference code cells consisting of
12 channel bit patterns after ETM-modulated is set to
5 an odd number. In the present embodiment, in order to
achieve high density, there is employed a mark edge
recording technique in which a location of "1"
coincides with a boundary position of a recording mark
or an emboss pit. For example, in the case where a
10 repetition pattern of "3T" ("100100100100100100100") is
followed, there occurs a case in which a length of a
recording mark or an emboss pit and a length of a space
between the mark and pit are slightly different from
each other depending on a recording condition or an
15 original master producing condition. In the case where
the PRML detecting technique has been employed, a level
value of a reproduction signal becomes very important.
As described previously, even in the case where the
length of the recording mark or emboss pit and the
20 length of the space between the mark and pit are
different from each other, there occurs a necessity of
correcting such slightly different component in a
circuit manner so as to enable signal detection stably
and precisely. Therefore, a reference code for tuning
25 a circuit constant has a space with a length of "3T",
like a recording mark or an emboss pit with a length of
"3T", thereby improving the precision of tuning a
circuit constant. Thus, if a pattern of "1001001" is
included as a reference code pattern according to the
present embodiment, the recording mark or emboss pit
having the length "3T"; and a space are always
5 arranged. In addition, circuit tuning also requires a
pattern in a non-dense state as well as a pattern
("1001001") having a high density. Therefore, in
consideration of that fact that a non-dense state
(pattern in which "0" is continuously and frequently
10 generated) is generated at a portion at which a pattern
of "1001001" has been excluded from among 12 channel
bit patterns after ETM-modulated and the number of
generated "l"s is set in an odd number, with respect to
a reference code pattern, a repetition of
15 "100100100000" is obtained as an optical condition, as
shown in FIG. 72. In order to ensure that the channel
bit pattern after modulated is produced as the pattern,
although not shown, there is a need for setting to
"A4h" a data word before modulated, when utilizing a
20 modulation table specified in an H format. This data
on "A4h" (hexadecimal notation) corresponds to a data
symbol "164" (decimal notation).
A description will be given below with respect to
how to produce specific data in accordance with the
25 above data conversion rule. First, data symbol "164"
(= "OA4h") is set to main data "DO to D2047" in the
data frame structure described previously. Next, a
data frame 1 to a data frame 15 are pre-scrambled in
advance by an initial preset number "OEh", and a data
frame 16 to a data frame 31 are pre-scrambled in
advance by an initial preset number "OFh". If pre-
5 scrambling is applied in advance, when scrambling is
applied in the data conversion rule described
previously, scrambling is applied in duplicate, and a
data symbol "164" (= "OA4h") appears as it is (when
scrambling is applied in duplicate, an original pattern
10 is returned). When pre-scrambling is applied to all of
the reference codes, each of which is formed of 32
physical sectors, DSV control cannot be made, and thus,
pre-scrambling cannot be applied to only data frame 0
in advance. After the foregoing scrambling has been
15 applied, if modulation is carried out, a pattern shown
in FIG. 72 is recorded on the information storage
medium.
Referring to FIG. 73, a description will be given
with respect to a comparison in data recording format
20 between a variety of information storage mediums in the
present embodiment. FIG. 73 (a) shows a data recording
format in a conventional read-only type information
storage medium DVD-ROM; a conventional write-once type
information storage medium DVD-R; and a conventional
25 DVD-RW; FIG. 73 (b) shows a data recording format in a
read-only type information storage medium in the
present embodiment; FIG. 73 (c) shows a data recording
format of a write-once type information storage medium
in the present embodiment; and FIG. 73 (d) shows a data
recording format of a rewritable-type information
storage medium. For the sake of comparison, ECC blocks
5 411 to 418 are shown as the same size. However, one
ECC block is composed of 16 physical sectors in the
conventional read-only type information storage medium
DVD-ROM shown in FIG. 73 (a); the conventional writeonce
type information storage medium DVD-R; and the
10 conventional rewritable type information storage medium
DVD-RW, whereas, in the present embodiment shown in
FIGS. 73 (b) to 73 (d) , one ECC block is composed of 32
physical sectors. The present embodiment is featured
in that guard areas 442 to 448 having the same length
15 as a sync frame length 433 is provided between ECC
blocks #1 411 to #8 418, as shown in FIGS. 73 (b) to
73 (d). In the conventional read-only type information
storage medium DVD-ROM, ECC blocks #1 411 to #8 418 are
continuously recorded as shown in FIG. 73 (a). If an
20 attempt is made to allocate compatibility in data
recording format with the conventional read-only type
information storage medium DVD-ROM by means of the
conventional write-once type information storage medium
DVD-R or the conventional rewritable type information
25 storage medium DVD-RW, if an additional writing or
rewriting process called restricted overwrite is
carried out, there has been a problem that part of the
ECC block is damaged due to overwriting and the data
reliability at the time of reproduction is
significantly degraded. In contrast, as in the present
embodiment, if guard areas 442 to 448 are arranged
5 between data fields (ECC blocks), there is attained
advantageous effect that an overwrite location is
restricted to the guard areas 442 to 448, and the data
damage in a data field (ECC block) can be prevented.
The present embodiment is secondarily featured in that
10 the lengths of the above guard areas 442 to 448 are
adjusted to conform with a sync frame length 433 which
is one sync frame size, as shown in FIGS. 73 (a) to 73
(d). As shown in FIGS. 62A and 62B, sync codes are
arranged in space in determined sync frame lengths 433
15 having 1116 channel bits, and a sync code position is
sampled by utilizing this predetermined cyclic space in
the sync code position detector unit 145 shown in
FIG. 11. In the present embodiment, there is attained
advantageous effect that, even if the guard areas 442
20 to 448 are encompassed at the time of reproduction by
making adjustment to conform with the length sync frame
length 433 of the guard areas 442 to 448, the sync
frame space is kept unchanged, thus facilitating sync
code position detection at the time of reproduction.
25 Further, in the present embodiment, sync data is
arranged in the guard area for the purpose of:
1) improving detection precision of the sync code
position detection while matching a generation
frequency of the sync codes even in a location
encompassing the guard areas 442 to 448; and
2) facilitating judgment of a position in a
5 physical sector including the guard areas 442 to 448.
Specifically, as shown in FIG. 75, a postamble
field 481 is formed at the start position of each of
the guard areas 442 to 468, and a sync code "SY1" of
sync code number "1" shown in FIG. 63 is arranged in
10 that postamble area 481. As is evident from FIGS. 62A
and 62B, combinations of sync code numbers of three
continuous sync codes in a physical sector are
different from each other in all locations. Further,
combinations of sync code numbers of three continuous
15 sync codes considering up to sync code numbers "1" in
the guard areas 442 to 448 are also different from each
other in all locations. Therefore, the judgment of a
position in physical sectors including a location of
the guard area as well as positional information in the
20 physical sectors can be made in accordance with sync
code number combinations of three continuous sync codes
in an arbitrary area.
FIG. 75 shows a detailed structure in the guard
areas 441 to 448 shown in FIG. 73. The present
25 embodiment is featured in that, although a structure in
physical sectors is composed of a combination of the
sync code 431 and sync data 432, the guard areas 441 to
448 is composed of a combination of a sync code 433 and
sync data 434 similarly; and, in an area of the sync
data 434 contained in the guard area #3 443, data is
arranged, the data being modulated in accordance with
5 the same modulation rule as the sync data 432 in
sectors. An area in one ECC block #2 412 composed of
32 physical sectors shown in FIG. 59 is referred to as
a data field 470 in the invention.
VFO (Variable Frequency Oscillator) areas 471 and
10 472 in FIG. 75 are utilized for synchronization of a
reference clock of an information reproducing apparatus
or an information recording/reproducing apparatus when
the data field 470 is reproduced. As the contents of
data recorded in the areas 471 and 472, the data before
15 modulated, in a common modulation rule described later,
is obtained as a continuous repetition of "7Eh", and a
channel bit pattern actually described after modulated
is obtained as a repetition of "010001 000100" (pattern
in which three "0" settings are repeated). In order to
20 obtain this pattern, it is necessary to set the start
bytes of the VFO areas 471 and 472 to State 2.
The pre-sync areas 477 and 478 indicates a
boundary position between the VFO areas 471 and 472 and
the data area 470, and a recording channel bit pattern
25 after modulated is a repetition of "100000 100000"
(pattern in which continuous five "0" settings are
repeated). The information reproducing apparatus or
the information recording reproducing apparatus detects
a pattern change position of a repetition pattern of
"100000 100000" in pre-sync areas 477 and 478 and
recognizes that the data area 470 approaches, from a
5 repetition pattern of "010001 000100" contained in the
VFO areas 471 and 472.
A postamble area 481 indicates an end position of
the data area 470 and designates a start position of
the guard area 443. A pattern in the postamble area
10 481 coincides with a pattern of "SY1" in a SYNC code
shown in FIG. 63, as described above.
An extra area 482 is an area used for copy control
or illegal copy protection. In particular, in the case
where this area is not used for copy control or illegal
15 copy protection, all "Os" are set by channel bits.
In a buffer area, data before modulated, which is
identical to that in the VFO areas 471 and 472, is
obtained as a continuous repetition of "7Eh", and the
actually recorded channel bit pattern after modulated
20 is obtained as a repetition pattern of "010001 000100"
(pattern in which continuous three 0 settings are
repeated). In order to obtain this pattern, it is
necessary to set the start bytes of the VFO areas 471
and 472 to State 2.
25 As shown in FIG. 75, a postamble area 481 in which
a pattern of "SYl" is recorded corresponds to the sync
code area 433; and an area from the immediately
succeeding extra area 482 to a pre-sync area 478
corresponds to the sync data area 434. An area from
the VFO area 471 to the buffer area 475 (namely, area
including the data area 470 and part of the preceding
5 and succeeding guard areas) is referred to as a data
segment 490 in the invention. This area indicates the
conditions different from those of a "physical segment"
described later. The data size of each item of data
shown in FIG. 75 is expressed by byte number of data
10 before modulated.
In the present embodiment, without being limited
to a structure shown in FIG. 75, the following method
can be employed as another embodiment. That is, the
pre-sync area 477 is arranged midway of the VOF areas
15 471 and 472 shown in FIG. 75 instead of allocating the
pre-sync area 477 at the boundary section between the
VOF area 471 and the data area 470. In such another
embodiment, a distance correlation is taken by spacing
a distance between a sync code "SYO" and the pre-sync
20 area 477 arranged at the start position of the data
block 470; the pre-sync area 477 is set as pseudo-Sync;
and the pre-sync area 477 is set as distance
correlation information on a real Sync position
(although it is different from a distance relevant to
25 another Sync position). If a real Sync position cannot
be detected, Sync is inserted into a position at which
the real position generated from a pseudo Sync position
would be detected. Another embodiment is featured in
that the pre-sync area 477 is thus spaced slightly from
real Sync ("SYO"). When the pre-sync area 477 is
arranged at the beginning of the VFO areas 471 and 472,
5 the role of the pre-sync becomes weaken because PLL of
a read clock is not locked. Therefore, it is desirable
that the pre-sync area 477 be arranged at the
intermediate position of the VFO areas 471 and 472.
In the invention, address information in a
10 recording type (rewritable-type or write-once)
information storage medium is recorded in advance by
using wobble modulation. The present embodiment is
featured in that phase modulation of ±90 degrees
(180 degrees) is used as a wobble modulation system,
15 and NRZ (Non Return to Zero) method is employed,
recording address information in advance with respect
to an information storage medium. A specific
description will be given with reference to FIG. 76.
In the present embodiment, with respect to address
20 information, the 1-address bit (referred to as an
address symbol) area 511 is expressed by a four-wobble
cycle, and a frequency and an amplitude/a phase are
matched everywhere in the 1-address bit area 511. In
the case where the same values of address bits are
25 continued, the same phase continuously lasts at the
boundary section of the 1-address bit areas 511 (at a
portion indicated by "triangular mark" shown in
FIG. 76). In the case where an address bit is
inverted, wobble pattern inversion (180-degree shift of
phase) occurs. In the wobble signal detector unit 135
of the information recording/reproducing apparatus
5 shown in FIG. 11, a boundary position of the above
address bit area 511 (location indicated by "triangular
mark" shown in FIG. 76) and a slot position 412 which
is a boundary position of a 1-wobble cycle are detected
at the same time. Although not shown in the wobble
10 signal detector unit 135, a PLL (Phase Lock Loop)
circuit is incorporated, and PLL is applied in
synchronism with both of the boundary position of the
above address bit area 511 and the slot position 412.
If the boundary position of this address bit area 511
15 or the slot position 412 is shifted, the wobble signal
detector unit 135 is out of synchronization, disabling
precise wobble signal reproduction (reading). A gap
between the adjacent slot positions 412 is referred to
as a slot gap 513. As this slot gap 513 is physically
20 closer, synchronization with a PLL circuit can be
easily obtained, enabling stable wobble signal
reproduction (reading of contained information). As is
evident from FIG. 76, this slot gap 513 coincides with
a 1-wobble cycle. As a wobble modulating method,
25 although an AM (Amplitude Modulation) system for
changing a wobble amplitude is easily affected by dust
or scratch adhering to the information storage medium
surface, the above phase modulation is hardly
comparatively affected by dust or scratch adhering to
the information storage medium surface because a change
of a phase is detected instead of a signal amplitude in
5 the above phase modulation. As another modulation
system, in an FSK (Frequency Shift Keying) system for
changing a frequency, a slot gap 513 is long with
respect to a wobble cycle, and synchronization of a PLL
circuit is relatively hardly obtained. Therefore, as
10 in the present embodiment, when address information is
recorded by wobble phase modulation, there is attained
advantageous effect that a slot gap is narrow, and
wobble signal synchronization is easily obtained.
As shown in FIG. 76, although binary data "1" or
15 "0" is assigned to the 1-address bit area 511, a method
for allocating bits in the present embodiment is shown
in FIG. 77. As shown on the left side of FIG. 77, a
wobble pattern, which first wobbles from the start
position of one wobble to the outer periphery side, is
20 referred to as an NPW (Normal Phase Wobble), and data
"0" is arranged. As shown at the right side, a wobble
pattern which first wobbles from the start position of
one wobble to the inner periphery side is referred to
as an IPW (Invert Phase Wobble), and data "1" is
25 arranged.
A description will be given with respect to an
address information recording format using wobble
modulation in an H format of a write-once type
information storage medium according to the invention.
An address information setting method using wobble
modulation in the present embodiment is featured in
5 that "allocation is carried out in units of the sync
frame length 433" shown in FIG. 73. As shown in
FIGS. 62A and 62B, one sector is composed of 26 sync
frames, and, as is evident from FIG. 56, one ECC block
is formed of 32 physical sectors. Thus, one ECC block
10 is composed of 32 physical sectors and is composed of
832 (= 26 x 327) sync frames. As shown in FIG. 73, a
length of the guard areas 442 to 468 which exist
between the ECC blocks 411 to 418 coincides with one
sync frame length 433, and thus, a length obtained by
15 adding one guard area 462 and one ECC block 411 to each
other is composed of 832 + 1 = 833 sync frames. Prime
factorization can be carried out into 833 = 7 x 17 x 7,
and thus, a structural allocation utilizing this
feature is provided. That is, a basic unit of data
20 capable of writing an area equal to a length of an area
obtained by adding one guard area and one ECC block to
each other is defined as a data segment 531 (A
structure in the data segment 490 shown in FIG. 75
coincides with one another regardless of the read-only
25 type information storage medium, the rewritable-type
information storage medium, or the write-once type
information storage medium); an area having the same
length as a physical length of one data segment 490 is
divided into "seven" physical segments, and address
information is recorded in advance in the form of
wobble modulation on a physical segment by segment
5 basis. A boundary position relevant to the data
segment 490 and a boundary position relevant to a
physical segment do not coincide with each other, and
are shifted by an amount described later. Further,
wobble data is divided into 17 WDU (Wobble Data Units),
10 respectively, on a physical segment by segment basis.
From the above formula, it is evident that seven sync
frames are arranged to a length of one wobble data
unit, respectively. Thus, a physical segment is
composed of 17 wobble data units, and seven physical
15 segment lengths are adjusted to conform with a data
segment length, thereby making it easy to allocate a
sync frame boundary and detect a sync code in a range
encompassing guard areas 442 to 468.
Each of the wobble data units #0 560 to #11 571 is
20 composed of: a modulation area 598 for 16 wobbles; and
non-modulation areas 592 and 593 for 68 wobbles, as
shown in FIGS. 78A to 78D. The present embodiment is
featured in that an occupying ratio of the nonmodulation
areas 592 and 593 with respect to a
25 modulation area is significantly large. In the
non-modulation areas 592 and 593, a group area or a
land area always wobbles at a predetermined frequency,
and thus, a PLL (Phase Locked Loop) is applied by
u L i l i z i n y LliH nun=iuodulation areas 592 and 593, making
it possible to stably sample (generate) a reference
clock when reproducing a recording mark recorded in the
5 information storage medium or a recording reference
clock used at the time of new recording. Thus, in the
present embodiment, an occupying ratio of the nonmodulation
areas 592 and 593 with respect to a
modulation area 598 is significantly increased, thereby
10 making it possible to remarkably improve the precision
of sampling (generating) a recording reference clock
and remarkably improving the stability of the sampling
(generation). That is, in the case where phase
modulation in wobbles has been carried out, if a
15 reproduction signal is passed through a band path
filter for the purpose of waveform shaping, there
appears a phenomenon that a detection signal waveform
amplitude after shaped is reduced before and after a
phase change position. Therefore, there is a problem
20 that, when the frequency of a phase change point due to
phase modulation increases, a waveform amplitude change
increases, and the above clock sampling precision
drops; and, conversely, if the frequency of a phase
change point in a modulation area is low, a bit shift
25 at the time of wobble address information detection is
likely to occur. Thus, in the present embodiment,
there is attained advantageous effect that a modulation
area and a non-modulation area due to phase modulation
configured, and an occupying ratio of the nonmodulation
area is increased, thereby improving the
above clock sampling precision. In the present
5 embodiment, a position of switching the modulation area
and the non-modulation area can be predicted in
advance. Thus, a reproduction signal is gated to
obtain a signal from the non-modulation area, making it
possible to carry out the above clock sampling from
10 that detection signal. In addition, in the case where
the recording layer 3-2 is composed of an organic dye
recording material using a principle of recording
according to the present embodiment, a wobble signal is
comparatively hardly taken in the case of using the
15 pre-groove shape/dimensions described in "3-2-D] Basic
characteristics relevant to pre-groove shape/dimensions
in the present embodiment" in "3-2) Description of
basic characteristics common to organic dye film in the
present embodiment". In consideration of this
20 situation, the reliability of wobble signal detection
is improved by significantly increasing an occupying
ratio of the non-modulation areas 590 and 591 with
respect to a modulation area, as described above. At
the boundary between the non-modulation areas 592 and
25 593 and the modulation area 598, an IPW area is set as
a modulation start mark of the modulation area 598 by
using four wobbles or six wobbles. At a wobble data
section shown in FIGS. 78C and 78D, allocation is
carried out so that wobble address areas (address bits
#2 to #0) wobble-modulated immediately after detecting
the IPW area which is this modulation start mark.
5 FIGS. 78A and 78B each show the contents in a wobble
data unit #0 560 which corresponds to a wobble sync
area 580 shown in FIG. 79 (c) described later; and
FIGS. 78C and 78D each show the contents in a wobble
data unit which corresponds to a wobble data section
10 from segment information 727 to a CRC code 726 shown in
FIG. 79 (c). FIGS. 78A and 78C each show a wobble data
unit which corresponds to a primary position 701 in a
modulation area described later; and FIGS. 78B and 78D
each show a wobble data unit which corresponds to a
15 secondary position 702 in a modulation area. As shown
in FIGS. 78A and 78B, in a wobble sync area 580, six
wobbles are allocated to the IPW area, and four wobbles
are allocated to an NPW area surrounded by the IPW
area. As shown in FIGS. 78C and 78D, four wobbles are
20 allocated to a respective one of the IPW area and all
of the address bit areas #2 to #0 in the wobble data
section.
FIG. 79 shows an embodiment relating to a data
structure in wobble address information in a write-once
25 type information storage medium. For the sake of
comparison, FIG. 79 (a) shows a data structure in
wobble address information of a rewritable-type
information storage medium. FIGS. 79 (a) and 79 (c)
show two embodiments relating to a data structure in
wobble address information in the write-once type
information storage medium.
5 In a wobble address area 610, three address bits
are set by 12 wobbles (referring to FIG. 76). Namely,
one address bit is composed of four continuous wobbles.
Thus, the present embodiment employs a structure in
which address information is arranged to be distributed
10 on three by three address bit basis. When the wobble
address information 610 is intensively recorded at one
site in an information storage medium, it becomes
difficult to detect all information when dust or
scratch adheres to the medium surface. As in the
15 present embodiment, there is attained advantageous
effect that: wobble address information 610 is arranged
to be distributed on a three by three address bit
(12 wobbles) basis included in one of the wobble data
units 560 to 576; and a set of information is recorded
20 on an integer multiple by multiple address bit basis of
three address bits, enabling information detection of
another item of information even in the case where it
is difficult to detect information in one site due to
dust or scratch.
25 As described above, the wobble address information
610 is arranged to be distributed, and the wobble
address information 610 is completely arranged on a one
by one physical segment basis, thereby making it
possible to identify address information on a physical
segment by segment basis, and thus, identify a current
position in physical segment units every time an
5 information recording/reproducing apparatus provides an
access.
In the present embodiment, an NRZ technique is
employed as shown in FIG. 76, and thus, a phase does
not change in four continuous wobbles in the wobble
10 address area 610. A wobble sync area 580 is set by
utilizing this characteristic. That is, a wobble
pattern which is hardly generated in the wobble address
information 610 is set with respect to the wobble sync
area 580, thereby facilitating allocation position
15 identification of the wobble sync area 580. The
present embodiment is featured in that, with respect to
wobble address areas 586 and 587 in which one address
bit is composed of four continuous wobbles, one address
bit length is set at a length other than four wobbles
20 at a position of the wobble sync area 580. That is, in
the wobble sync area 580, as shown in FIGS. 78A and
78B, an area (IPW area) in which a wobble bit is set to
"1" is set as a wobble pattern change which does not
occur in the wobble data section as shown in FIGS. 78C
25 and 78D such as "six wobble —» four wobbles —»
six wobbles". When a method for changing a wobble
cycle as described above is utilized as a specific
method for setting a wobble pattern which can be hardly
generated in the wobble data section with respect to
the wobble sync area 580, the following advantageous
effects can be attained:
5 1) Wobble detection (wobble signal judgment) can
be stably continued without distorting PLL relating to
the slot position 512 (FIG. 76) of a wobble which is
carried out in the wobble signal detector unit 135
shown in FIG. 11; and
10 2) A wobble sync area 580 and modulation start
marks 561 and 562 can be easily detected due to a shift
of an address bit boundary position generated in the
wobble signal detector unit 135 shown in FIG. 11.
As shown in FIGS. 78A to 78D, the present
15 embodiment is featured in that the wobble sync area 580
is formed in 12 wobble cycles, and a length of the
wobble sync area 580 is made coincident with three
address bit lengths. In this manner, all the
modulation areas (for 16 wobbles) in one wobble data
20 unit #0 560 are arranged to the wobble sync area 580,
thereby improving detection easiness of the start
position of wobble address information 610 (allocation
position of wobble sync area 580). This wobble sync
area 580 is arranged in the first wobble data unit in a
25 physical segment. Thus, there is attained advantageous
effect that the wobble sync area 580 is arranged to the
start position in a physical segment, whereby a
boundary position of the physical segment can be easily
sampled merely by detecting a position of the wobble
sync area 580.
As shown in FIGS. 78C and 78D, in wobble data
5 units #1 561 to #11 571, the IPW area (refer to
FIG. 77) is arranged as a modulation start mark at the
start position, the area preceding address bits #2 to
#0. The waveform of NPW is continuously formed in the
non-modulation areas 592 and 593 arranged at the
10 preceding position. Thus, the wobble signal detector
unit 135 shown in FIG. 11 detects a turning point from
NPW to IPW is detected, and samples the position of the
modulation start mark.
As a reference, the contents of wobble address
15 information 610 contained in a rewritable-type
information storage medium shown in FIG. 79 (a) are as
follows:
1) Physical segment address 601
- Information indicating a physical segment number
20 in a track (within one cycle in an information storage
medium 221);
2) Zone address 602
- This address indicates a zone number in the
information storage medium 221; and
25 3) Parity information 605
- This information is set for error detection at
the time of reproduction from the wobble address
information 610; 14 address bits from reserved
information 604 to the zone address 602 are
individually added in units of address bits; and a
display as to whether or not a result of the addition
5 is an even number or an odd number is made. A value of
the parity information 605 is set so that a result
obtained by taking exclusive OR in units of address
bits becomes "1" with respect to a total of 15 address
bits including one address bit of this address parity
10 information 605.
4) Unity area 608
- As described previously, each wobble data unit
is set so as to be composed of a modulation area 598
for 16 wobbles and non-modulation areas 592 and 593 for
15 68 wobbles, and an occupying ratio of the nonmodulation
areas 592 and 593 with respect to the
modulation area 598 is significantly increased.
Further, the precision and stability of sampling
(generation) of a reproducing reference clock or a
20 recording reference clock is improved more remarkably
by increasing the occupying ratio of the non-modulation
areas 592 and 593. The NPW area is fully continuous in
a unity area 608, and is obtained as a non-modulation
area having its uniform phase.
25 FIG. 79 (a) shows the number of address bits
arranged to each item of the above described
information. As described above, the wobble address
information 610 is divided on a three by three address
bits, and the divided items of the information are
arranged to be distributed in each wobble data unit.
Even if a burst error occurs due to the dust or scratch
5 adhering to a surface of an information storage medium,
there is a very low probability that such an error
propagates across the wobble data units which are
different from each other. Therefore, a contrivance is
made so as to reduce to the minimum the count
10 encompassing the different wobble data units as
locations in which the same information is recorded and
to match the turning point of each items of information
with a boundary position of a wobble data unit. In
this manner, even if a burst error occurs due to the
15 dust or scratch adhering to a surface of an information
storage medium, and then, specific information cannot
be read, the reliability of reproducing of wobble
address information is improved by enabling reading of
another item of information recorded in another one of
20 the wobble data units.
As shown in FIGS. 79 (a) to 79 (d), the present
embodiment is featured in that the unity areas 608 and
609 are arranged at the end in the wobble address
information 610. As described above, in the unity
25 areas 608 and 609, a wobble waveform is formed in the
shape of NPW, and thus, the NPW continuously lasts in
substantially three continuous wobble data units.
There is attained advantageous effect that the wobble
signal detector unit 135 shown in FIG. 11 makes a
search for a location in which NPW continuously lasts
in a length for three wobble data units 576 by
5 utilizing this feature, thereby making it possible to
easily sample a position of the unity area 608 arranged
at the end of the wobble address information 610, and
to detect the start position of the wobble address
information 610 by utilizing the positional
10 information.
From among a variety of address information shown
in FIG. 79 (a), a physical segment address 601 and a
zone address 602 indicate the same values between the
adjacent tracks, whereas a value changes between the
15 adjacent tracks in a groove track address 606 and a
land track address 607. Therefore, an indefinite bit
area 504 appears in an area in which the groove track
address 606 and the land track address 607 are
recorded. In order to reduce a frequency of this
20 indefinite bit, in the present embodiment, an address
(number) is displayed by using a gray code with respect
to the groove track address 606 and the land track
address 607. The gray code denotes a code in the case
where a code after converted when an original value
25 changes by "1" only changes by "one bit" anywhere. In
this manner, the indefinite bit frequency is reduced,
making it possible to detect and stabilize a
reproduction signal from a recording mark as well as a
wobble detecting signal.
As shown in FIGS. 79 (b) and 79 (c), in a writeonce
type information storage medium as well, as in the
5 rewritable-type information storage medium, a wobble
sync area 580 is arranged at the start position of a
physical segment, thereby making it easy to detect the
start position of the physical segment or a boundary
position between the adjacent segments. Type
10 identification information 721 on the physical segment
shown in FIG. 79B indicates an allocation position in
the physical segment as in the wobble sync pattern
contained in the above described wobble sync area 580,
thereby making it possible to predict in advance an
15 allocation location of another modulation area 598 in
the same physical segment and to prepare for next
modulation area detection. Thus, there is attained
advantageous effect that the precision of signal
detection (judgment) in a modulation area can be
20 improved. Specifically,
When type identification information 721 on a
physical segment is set to "0", it denotes that all the
items of information in the physical segment shown in
FIG. 81 (b) are arranged at a primary position or that
25 a primary position and a secondary position shown in
FIG. 81 (d) are mixed; and
When type identification information 721 of a
physical segment is set to "1", all items of
information in a physical segment are arranged at a
secondary position, as shown in FIG. 81 (c).
According to another embodiment relevant to the
5 above described embodiment, it is possible to indicate
an allocation location of a modulation area in a
physical segment by using a combination between a
wobble sync pattern and type identification information
721 on a physical segment. By using the combination of
10 the two types of information described previously,
three or more types of allocation patterns of
modulation areas shown in FIGS. 81 (b) to 81 (d) can be
expressed, making it possible to provide a plurality of
allocation patterns of the modulation areas. While the
15 above described embodiment shows an allocation location
of a modulation area in a physical segment which
includes a wobble sync area 580 and type identification
information 721 on a physical segment, the invention is
not limited thereto. For example, as another
20 embodiment, the wobble sync area 580 and the type
identification information 721 on the physical segment
may indicate an allocation location of a modulation
area in a next physical segment. By doing this, in the
case where tracking is carried out continuously along a
25 groove area, there is attained advantageous effect that
the allocation location of the modulation area in the
next physical segment can be identified in advance, and
a long preparation time for detecting a modulation area
can be taken.
Layer number information 722 in a write-once type
information storage medium shown in FIG. 79 (b)
5 indicates either of the recording layers from among a
single-sided single-layer or a single-sided doublelayer.
This information denotes:
- "LO later" in the case of a single-sided singlelayer
medium or a single-sided double-layer medium when
10 "0" is set (a front layer at the laser light beam
incident side); and
- "LI layer" of a single-sided double-layer when
"1" is set (a rear layer in viewed from the laser light
beam incident side).
15 Physical segment sequence information 724
indicates an allocation sequence of relative physical
segments in the same physical segment block. As is
evident as compared with FIG. 79 (a), the start
position of the physical segment sequence information
20 724 contained in wobble address information 610
coincides with that of a physical segment address 601
contained in a rewritable-type information storage
medium. The physical segment sequence information
position is adjusted to conform with the
25 rewritable-type medium, thereby making it possible to
improve compatibility between medium types and to share
or simplify an address detection control program using
a wobble signal in an information recording/reproducing
apparatus in which both of a rewritable-type
information storage medium and a write-once type
information storage medium can be used.
5 A data segment address 725 shown in FIG. 79 (b)
describes address information on a data segment in
numbers. As has already been described, in the present
embodiment, one ECC block is composed of 32 sectors.
Therefore, the least significant five bits of a
10 physical sector number of a sector arranged at the
beginning in a specific ECC block coincides with that
of a sector arranged at the start position in the
adjacent ECC block. In the case where a physical
sector number has beet set so that the least
15 significant five bits of the physical sector number of
a sector arranged in an ECC block are "00000", the
values of the least significant six bits or more of the
physical sector numbers of all the sectors which exist
in the same ECC block coincide with each other.
20 Therefore, the least significant five bit data of the
physical sector number of the sectors which exist in
the same ECC block is eliminated, and address
information obtained by sampling only the least
significant six bits or more is defined as an ECC block
25 address (or ECC block address number). A data segment
address 725 (or physical segment block number
information) recorded in advance by wobble modulation
coincides with the above ECC block address. Thus, when
positional information on a physical segment block due
to wobble modulation is indicated by a data segment
address, there is advantageous effect that a data
5 amount decreases on five by five bit basis as compared
with when the address is displayed by a physical sector
number, simplifying current position detection at the
time of an access.
A CRC code 726 shown in FIGS. 79 (b) and 79 (c) is
10 a CRC code (error correction code) arranged to 24
address bits from physical segment type identification
information 721 to the data segment address 725 or a
CRC code arranged to 24 address bits from segment
information 727 to the physical segment sequence
15 information 724. Even if a wobble modulation signal is
partially mistakenly read, this signal can be partially
corrected by this CRC code 726.
In a write-once type information storage medium,
an area corresponding to 15 address bits is arranged to
20 the unity area 609, and an NPW area is fully arranged
in five wobble data units 12 to 16 (the modulation area
598 does not exist).
A physical segment block address 728 shown in
FIG. 79 (c) is an address set for each physical segment
25 block which configure one unit from seven physical
segments, and a physical segment block address relevant
to the first segment block in the data lead-in area
DTRDI is set to "1358h". The values of the physical
segment block addresses are sequentially added one by
one from the first physical segment block contained in
the data lead-in area DTLDI to the last physical
5 segment block contained in the data lead-out area
DTLDO, including the data area DTA.
The physical segment sequence information 724
denotes the sequence of each of the physical segments
in one physical segment block, and "0" is set to the
10 first physical segment, and "6" is set to the last
physical segment.
The embodiment shown in FIG. 79 (c) is featured in
that the physical segment block address 728 is arranged
at a position which precedes the physical segment
15 sequence information 724. For example, as in the RMD
field 728 shown in FIG. 53, address information is
often managed by this physical segment block address.
In the case where an access is provided to a
predetermined segment block address in accordance with
20 these items of management information, first, the
wobble signal detector unit 135 shown in FIG. 11
detects a location of the wobble sync area 580 shown in
FIG. 79 (c), and then, sequentially decodes items of
information recorded immediately after the wobble sync
25 area 580. In the case where a physical segment block
address exists at a position which precedes the
physical segment sequence information 724, first, the
physical segment block address is decoded, and it is
possible to judge whether or not a predetermined
physical segment block address exists without decoding
the physical segment sequence information 724. Thus,
5 there is advantageous effect that access capability
using a wobble address is improved.
The segment information 727 is composed of type
identification information 721 and a reserved area 723.
The type identification information 721 denotes an
10 allocation location of a modulation area in a physical
segment. In the case where the value of this type
identification information 721 is set to "Ob", it
denotes a state shown in FIG. 81 (b) described layer.
In the case where the information is set to "Ib", it
15 denotes a state shown in FIG. 81 (c) or FIG. 81 (d)
described later.
The present embodiment is featured in that type
information identification 721 is arranged immediately
after the wobble sync area 580 in FIG. 79 (c). As
20 described above, first, the wobble signal detector unit
135 shown in FIG. 11 detects a location of the wobble
sync area 580 shown in FIG. 79 (c), and then,
sequentially decodes the items of information recorded
immediately after the wobble sync area 580. Therefore,
25 the type identification information 721 is arranged
immediately after the wobble sync area 580, thereby
enabling an allocation location check of a modulation
area in a physical segment immediately. Thus, high
speed access processing using a wobble address can be
achieved.
In the write-once type information storage medium
5 according to the present embodiment, a recording mark
is formed on a groove area, and a CLV recording system
is employed. In this case, as described previously, a
wobble slot position is shifted between the adjacent
tracks, and thus, interference between the adjacent
10 wobbles is likely to occur with a wobble reproduction
signal. In order to eliminate this effect, in the
present embodiment, a contrivance is made to shift a
modulation area so that modulation areas do not overlap
each other between the adjacent tracks.
15 Specifically, as shown in FIG. 80, a primary
position 701 and a secondary position 702 can be set in
an allocation location of a modulation area.
Basically, assuming that after allocation has been
fully carried out in the primary position, there occurs
20 a location in which modulation areas partially overlap
between the adjacent tracks, there is employed a method
for partially shift the modulation area to the
secondary position. For example, in FIG. 80, when a
modulation area of a groove area 505 is set at the
25 primary position, a modulation area of the adjacent
groove area 502 and a modulation area of a groove area
506 partially overlap on each other. Thus, the
modulation area of the groove area 505 is shifted to
the secondary position. In this manner, there is
attained advantageous effect that a wobble address can
be stably reproduced by preventing the interference
5 between the modulation areas of the adjacent tracks in
a reproduction signal from a wobble address.
The specific primary position and secondary
position relating to a modulation area is set by
switching an allocation location in the same wobble
10 data unit. In the present embodiment, an occupying
ratio of a non-modulation area is set to be higher than
a modulation area so that, the primary position and the
secondary position can be switched merely by making a
mere allocation change in the same wobble data unit.
15 Specifically, in the primary position 701, as shown in
FIGS. 78 (a) and 78 (c), the modulation area 598 is
arranged at the start position in one wobble data unit.
In the secondary position 702, as shown in FIGS. 78 (b)
and 78 (d), the modulation area 598 is arranged at the
20 latter half position in one of the wobble data unit 560
to 571.
A coverage of the primary position 701 and the
secondary position 702 shown in FIGS. 78 (a) to 78 (d),
i.e., a range in which the primary position or the
25 secondary position continuously lasts is defined in the
rage of physical segments in the present embodiment.
That is, as shown in FIGS. 81 (b) to 81 (d) , after
three types (plural types) of allocation patterns of
modulation areas in the same physical segment have been
provided, when the wobble signal detector unit 135
shown in FIG. 11 identifies an allocation pattern of a
5 modulation area in a physical segment from the
information contained in the type identification
information 721 on a physical segment, the allocation
location of another modulation area 598 in the same
physical segment can be predicted in advance. As a
10 result, there is attained advantageous effect that
preparation for detecting a next modulation area can be
made, thus making it possible to improve the precision
of signal detection (judgment).
FIG. 81 (b) shows allocation of wobble data units
15 in a physical segment, wherein the number described in
each frame indicate wobble data unit numbers in the
same physical segment. A 0-th wobble data unit are
referred to as a sync field 711 as indicated at a first
stage. A wobble sync area exists in a modulation area
20 in this sync field. First to eleventh wobble data
units are referred to as an address field 712. Address
information is recorded in a modulation area contained
in this address field 712. Further, in twelfth to
sixteenth wobble data units, all of the wobble patterns
25 are formed in an NPW unity field 713.
A mark "P" described in FIGS. 81 (b), 81 (c) and
81 (d) indicates that a modulation area is set at a
primary position in a wobble data unit; and a mark "S"
indicates that a modulation area is set at a secondary
position in a wobble data unit. A mark "U" indicates
that a wobble data unit is included in a unity field
5 713, and a modulation area does not exist. An
allocation pattern of a modulation area shown in
FIG. 81 (b) indicates that all the areas in a physical
segment are set at the primary position; and an
allocation pattern of a modulation area shown in
10 FIG. 81 (c) indicates all areas in a physical segment
are set at the secondary position. In FIG. 81 (d), the
primary position and the secondary position are mixed
in the same physical segment; a modulation area is set
at the primary position in each of 0-th to fifth wobble
15 data units, and a modulation area is set at the
secondary position in each of sixth to eleventh wobble
data units. As shown in FIG. 81 (d), the primary
positions and the secondary positions are half divided
with respect to an area obtained by adding a sync field
20 711 and an address field 712, thereby making it
possible to finely prevent an overlap of modulation
areas between the adjacent tracks.
Now, a description will be given with respect to a
method for recording the data segment data described
25 previously with respect to the physical segment or the
physical segment block in which address information is
recorded in advance by wobble modulation described
above. Data is recorded in recording cluster units
serving as units of continuously recording data in both
of a rewritable-type information storage medium and a
write-once type information storage medium. FIGS. 82A
5 and 82B show a layout in this recording cluster. In
recording clusters 540 and 542, one or more (integer
numbers) of data segments continuously lasts, and an
expanded guard field 528 or 529 is set at the beginning
or at the end of the segment. The expanded guard
10 fields 528 and 529 are set in the recording clusters
540 and 542 so as to be physically overlapped and
partially overwritten between the adjacent recording
clusters so as not to produce a gap between the
adjacent recording clusters when data is newly
15 additionally written or rewritten in units of the
recording clusters 540 and 542. As the position of
each of the expanded guard fields 528 and 529 set in
the recording clusters 540 and 542, in the embodiment
shown in FIG. 82A, the expanded guard field 528 is
20 arranged at the end of the recording cluster 540. In
the case where this method is used, the expanded guard
field 528 follows a post amble area 526 shown in
FIG. 83 (a). Thus, in particular, in the write-once
type information storage medium, the post-amble area
25 526 is not mistakenly damaged at the time of rewriting;
protection of the post-amble area 526 at the time of
rewriting can be carried out; and the reliability of
position detection using the post amble area 526 at the
time of data reproduction can be arranged. As another
embodiment, as shown in FIG. 82B, the expanded guard
field 529 can also be arranged at the beginning of the
5 recording cluster 542. In this case, as is evident
from a combination of FIG. 82B and FIGS. 83 (a) to
83 (f), the expanded guard field 529 immediately
precedes a VFO area 522. Thus, at the time of
rewriting or additional writing, the VFO area 522 can
10 be sufficiently taken long, and thus, a PLL lead-in
time relating to a reference clock at the time of
reproduction of a data field 525 can be taken long,
making it possible to improve the reliability of
reproduction of data recorded in the data field 525.
15 In this way, there is attained advantageous effect that
a structure composed of data segments in the case where
one or more recording clusters denote writing units is
provided, thereby making it possible to facilitate a
mixing recording process with respect to the same
20 information storage medium, PC data (PC files) of which
a small amount of data is often rewritten many times
and AV data (AV file) of which a large amount of data
is continuously recorded one time. That is, with
respect to data used for a personal computer, a
25 comparatively small amount of data is often rewritten
many times. Therefore, a recording method suitable for
PC data is obtained by minimally setting data units of
rewriting or additional writing. In the present
embodiment, as shown in FIG. 56, an ECC block is
composed of 32 physical sectors. This, a minimum unit
for efficiently carrying out rewriting or additional
5 writing is obtained by carrying out rewriting or
additional writing in data segment units including only
one ECC block. Therefore, a structure in the present
embodiment in which one or more data segments are
included in a recording cluster which denotes rewriting
10 units or additional writing units is obtained as a
recording structure suitable for PC data (PC files).
In AV (Audio Video) data, it is necessary to
continuously record a very large amount of video image
information and voice information smoothly without any
15 problem. In this case, continuously recorded data is
collectively recorded as one recording cluster. At the
time of AV data recording, when a random shift amount,
a structure in a data segment, or a data segment
attribute and the like is switched on a data segment by
20 segment basis configuring one recording cluster, a
large amount of time is required for such a switching
process, making it difficult to carry out a continuous
recording process. In the present embodiment, as shown
in FIGS. 82A and 82B, it is possible to provide a
25 recording format suitable for AV data recording for
continuously recording a large amount of data by
configuring a recording cluster while data segments in
the same format (without changing an attribute or a
ransom shift amount and without inserting specific
information between data segments) are continuously
arranged. In addition, a simplified structure in a
5 recording cluster is achieved, and simplified recording
control circuit and reproduction detector circuit are
achieved, making it possible to reduce the price of an
information recording/reproducing apparatus or an
information reproducing apparatus. A data structure in
10 recording cluster 540 in which data segments (excluding
the expanded guard field 528) in the recording cluster
shown in FIGS. 82A and 82B are continuously arranged is
completely identical to those of the read-only
information storage medium shown in FIG. 73 (b) and the
15 write-once type information storage medium shown in
FIG. 73 (c). In this way, a common data structure is
provided among all of the information storage mediums
regardless of the read-only type, the write-once type,
or the rewritable-type, thus allocating medium
20 compatibility. In addition, a detector circuit of the
information recording/reproducing apparatus or the
information reproducing apparatus whose compatibility
has been arranged can be used in common; high
reliability of reproduction can be arranged; and price
25 reduction can be achieved.
By employing the structure shown in FIGS. 82A and
82B, random shift amounts of all the data segments
inevitably coincide with each other in the recording
cluster. In the rewritable-type information medium, a
recording cluster is recorded by random shifting. In
the present embodiment, the random shift amounts of all
5 the data segments coincide with each other in the same
recording cluster 540. Thus, in the case where
reproduction has been carried out across the different
data segments from each other in the same recording
cluster 540, there is no need for synchronization
10 adjustment (phase resetting) in a VFO area (reference
numeral 522 in FIG. 83 (d)), making it possible to
simplify a reproduction detector circuit at the time of
continuous reproduction and to allocate high
reliability of reproduction detection.
15 FIGS. 83 shows a method for recording data to be
rewritably recorded in a rewritable-type information
storage medium. Now, although a description will be
given while focusing on a rewritable-type information
storage medium, it should be noted that an additional
20 writing method relevant to a write-once type
information storage medium is basically identical to
the above recording method. A layout in the recording
cluster in a write-once type information storage medium
according to the present embodiment will be described
25 in way of example employing a layout shown in FIG. 82A.
The present embodiment is not limited thereto, and a
layout shown in FIG. 82B may be employed for a
rewritable-type information storage medium. In the
present embodiment, rewriting relating to rewritable
data is carried out in units of the recording clusters
540 and 541 shown in FIGS. 82B and 83 (e). As
5 described later, one recording cluster is composed of
one or more data segments 529 to 531 and an expanded
guard field 528 arranged at the end. That is, the
start position of one recording cluster 631 coincides
with that of the data segment 531, and the cluster
10 starts from the VFO area 522. In the case where a
plurality of data segments 529 and 530 are continuously
recorded, the plurality of data segments 529 and 530
are continuously arranged in the same recording cluster
531. In addition, the buffer area 547 which exists at
15 the end of the data segment 529 and the VFO area 532
which exists at the beginning of a next data segment
continuously last, and thus, a phase (of a recording
reference clock) at the time of recording) between
these areas coincides with one another. When
20 continuous recording terminates, an expanded guard area
528 is arranged at the end position of the recording
cluster 540. The data size of this expanded guard area
528 is equal to the size for 24 data bytes as data
before modulated.
25 As is evident from a correlation between FIGS. 83
(a) and 83 (c), rewritable-type guard areas 461 and 462
each include: post amble areas 546 and 536; extra areas
544 and 534; buffer areas 547 and 537; VFO areas 532
and 522; and pre-sync areas 533 and 523, and an
expanded guard field 528 is arranged only in location
in which continuous recording terminates. The present
5 embodiment is featured in that rewriting or additional
writing is carried out so that the expanded guard area
528 and the succeeding VFO area 522 partially overlap
each other at a duplicate site 591 at the time of
rewriting. By rewriting or additional writing while
10 partial duplication is maintained, it is possible to
prevent a gap (area in which no recording mark is
formed) from being produced between the recording
clusters 540 and 541. In addition, a stable
reproduction signal can be detected by eliminating
15 inter-layer cross talk in an information storage medium
capable of carrying out recording in a single-sided
double recording layer.
The data size which can be rewritten in one data
segment in the present embodiment is 67 + 4 + 77376 + 2
20 + 4 + 16 = 77469 (data bytes). One wobble data unit
560 is 6 + 4 + 6 + 68 = 84 (wobbles). One physical
segment 550 is composed of 17 wobble data units, and a
length of seven physical segments 550 to 556 coincides
with that of one data segment 531. Thus, 84 x 17 x 7 =
25 9996 (wobbles) are arranged in the length of one data
segment 531. Therefore, from the above formula,
77496/9996 =7.75 (data bytes/wobble) corresponds to
one wobble.
As shown in FIG. 84, an overlap portion of the
succeeding VFO area 522 and the expanded guard field
528 follows 24 wobbles from the start position of a
5 physical segment, and the starting 16 wobbles of a
physical segment 550 are arranged in a wobble sync area
580, and the subsequent 68 wobbles are arranged in a
non-modulation area 590. Therefore, an overlap portion
of the VFO area 522 which follows 24 wobbles and the
10 expanded guard field 528 is included in the nonmodulation
area 590. In this way, the start position
of a data segment follows the 24 wobbles from the start
position of a physical segment, whereby the overlap
portion is included in the non-modulation area 590. In
15 addition, a detection time and a preparation time for
recording process of the wobble sync area 580 can be
sufficiently taken, and thus, a stable and precise
recording process can be guaranteed.
A phase change recording film is used as a
20 recording film of the rewritable-type information
storage medium in the present embodiment. In the phase
change recording film, degradation of the recording
film starts in the vicinity of the rewriting start/end
position. Thus, if recording start/recording end at
25 the same position is repeated, there occurs a
restriction on the number of rewritings due to the
degradation of the recording film. In the present
embodiment, in order to alleviate the above described
problem, at the time of rewriting, J^+i/l2 data bytes
are shifted as shown in FIG. 84, and the recording
start position is shifted at random.
5 Although the start position of the expanded guard
field 528 coincides with that of the VFO area 522 in
order to explain a basic concept in FIGS. 83 (c) and 83
(d), strictly, the start position of the VFO area 522
is shifted at random, as shown in FIG. 84, in the
10 present embodiment.
A phase change recording film is used as a
recording film in a DVD-RAM disk which is a current
rewritable-type information storage medium as well, the
start/end positions of recording is shifted at random
15 for the purpose of improving the rewriting count. The
maximum shift amount range when random shifting has
been carried out in the current DVD-RAM disk is set to
8 data bytes. A channel bit length (as data after
modulated, to be recorded in a disk) in the current
20 DVD-RAM disk is set to 0.143 |^m on average. In the
rewritable-type information storage medium according to
the present embodiment, an average length of channel
bits is obtained as (0.087 + 0.093)/2 = 0.090 (\m) . In
the case where a length of a physical shift range is
25 adjusted to conform with the current DVD-RAM disk, by
using the above value, the required minimal length
serving as a random shift range in the present
embodiment is obtained as:
8 bytes x (0.143 |am/0.090 jam) = 12.7 bytes
In the present embodiment, in order to allocate
easiness of a reproduction signal detecting process,
5 the unit of random shift amount has been adjusted to
conform with "channel bits" after modulated. In the
present embodiment, ETM modulation (Eight to Twelve
modulation) for converting 8 bits to 12 bits is used,
and thus, formula expression which indicates a random
10 shift amount is designated by Jm/12 (data bytes) while
a data byte is defined as a reference. Using the value
of the above formula, a value which can be taken by Jm
is 12.7 x 12 = 152.4, and thus, Jm ranges 0 to 152.
For the above described reason, in the range meeting
15 the above formula, a length of the random shift range
coincides with the current DVD-RAM disk, and the
rewriting count similar to the current DVD-RAM disk can
be guaranteed. In the present embodiment, a margin is
slightly provided with respect to the required minimal
20 length in order to allocate the current or more
rewriting count, and the length of the random shift
range has been set to 14 (data bytes). From these
formulas, 14 x 12 = 168 is established, and thus, a
value which can be taken by Jm has been set in the
25 range of 0 to 167. As described above, the random
shift amount is defined in a range which is wider than
Jm/12 (0 range relevant to the random shift amount coincides
with that of the current DVD-RAM. Thus, there is
attained advantageous effect that the repetition
recording count similar to that of the current DVD-RAM
5 can be guaranteed.
In FIG. 83 (c), the lengths of the buffer area 547
and the VFO area 532 in the recording cluster 540
become constant. As is evident from FIG. 82 (a) as
well, the random shift amount Jm of all the data
10 segments 529 is obtained as the same value everywhere
in the same recording cluster 540. In the case of
continuously recording one recording cluster 540 which
includes a large amount of data segments, a recording
position is monitored from a wobble. That is, a
15 position of the wobble sync area 580 shown in FIGS. 79
(a) to 79 (c) is detected, and, in the non-modulation
areas 592 and 593 shown in FIGS. 78 (c) and 78 (d), the
check of the recording position on the information
storage medium is made at the same time as recording
20 while the number of wobbles is counted. At this time,
a wobble slip (recording at a position shifted by one
wobble cycle) occurs due to mistaken wobble count or
rotation non-uniformity of a rotary motor which rotates
the information storage medium, and the recording
25 position on the information storage medium is rarely
shifted. The information storage medium according to
the present embodiment is featured in that, in the case
where a recording position shift generated as described
above has been detected, adjustment is made in the
rewritable-type guard area 461 shown in FIG. 83 (a),
and recording timing correction is carried out in the
5 guard area 461. Now, an H format will be described
here. This basic concept is employed in a B format,
described later. In FIGS, 83 (a) to 83 (f), although
important information for which bit missing or bit
duplication cannot be allowed is recorded in a
10 postamble area 546, an extra area 544, and a pre-sync
area 533, a specific pattern is repeated in the buffer
area 547 and the VFO area 532. Thus, as long as this
repetition boundary position is arranged, missing or
duplication of only one pattern is allowed. Therefore,
15 in the present embodiment, in particular, adjustment is
made in the buffer area 547 or the VFO area 532, and
recording timing correction is carried out.
As shown in FIG. 84, in the present embodiment, an
actual start point position defined as a reference of
20 position setting is set so as to match a position of
wobble amplitude "0" (wobble center). However, the
position detecting precision of a wobble is low, and
thus, in the present embodiment, the actual start point
position allows a shift amount up to a maximum of ±1
25 data byte", as "±1 max" in FIG. 84 is described.
In FIGS. 83 (a) to 83 (f) and 84, the random shift
amount in the data segment 530 is defined as Jm (as
described above, the random shift amounts of all the
data segments 529 coincide with each other in the
recording cluster 540); and the random shift amount of
the data segment 531 to be additionally written is
5 defined as Jm+i- As a value which can be taken by Jm
and Jm+i shown in the above formula, for example, when
an intermediate value is taken, Jm = Jm+]_ = 84 is
obtained. In the case where the positional precision
of an actual start point is sufficiently high, the
10 start position of the expanded guard field 528
coincides with that of the VFO area 522, as shown in
FIGS. 83 (c) and 83 (d).
In contrast, after the data segment 530 is
recorded at the maximum back position, in the case
15 where the data segment 531 to be additionally written
or rewritten has then been recorded in the maximum
front position, the start position of the VFO area 522
may enter a maximum 15 data bytes in the buffer area
537. Specific important information is recorded in the
20 extra area 534 that immediately precedes the buffer
area 537. Therefore, in the present embodiment, a
length of the buffer area 537 requires 16 data bytes or
more. In the embodiment shown in FIG. 83 (c), a data
size of the buffer area 537 is set to 15 data bytes in
25 consideration of a margin of one data byte.
As a result of a random shift, if a gap occurs
between the expanded guard area 528 and the VFO area
522, in the case where a single-sided double recording
layer structure has been employed, there occurs an
inter-layer crosstalk at the time of reproduction due
to that gap. Thus, even if a random shift is carried
5 out, a contrivance is made such that the expanded guard
field 528 and the VFO area 522 partially overlap each
other, and a gap is not produced. Therefore, in the
present embodiment, it is necessary to set the length
of the expanded guard field 528 to be equal to or
10 greater than 15 data bytes. The succeeding VFO area
522 sufficiently takes 71 data bytes. Thus, even if an
overlap area of the expanded guard field 528 and the
VFO area 522 slightly widens, there is no obstacle at
the time of signal reproduction (because a time for
15 obtaining synchronization of reproduction reference
clocks is sufficiently arranged in the VFO area 522
which does not overlap). Therefore, it is possible to
set the value of the expanded guard field 528 to be
greater than 15 data bytes. As has already been
20 described, a wobble strip rarely occurs at the time of
continuous recording, and a recording position may be
shifted by one wobble cycle. One wobble cycle
corresponds to 7.75 (=?8) data bytes, and thus, in the
present embodiment, a length of the expanded guard
25 field 528 is set to equal to or greater than 23 (= 15 +
8) data bytes. In the embodiment shown in FIG. 83 (c),
like the buffer area 537, the length of the expanded
guard field 528 is set to 24 data bytes in
consideration of a margin of one data byte similarly.
In FIG. 83 (e), it is necessary to precisely set
the recording start position of the recording cluster
5 541. The information recording/reproducing apparatus
according to the present embodiment detects this
recording start position by using a wobble signal
recorded in advance in the rewritable-type or writeonce
type information storage medium. As shown in
10 FIGS. 78A to 78D, in all areas other than the wobble
sync area 580, a pattern changes from NPW to IPW in
units of four wobbles. In comparison, in the wobble
sync area 580, wobble switching units are partially
shifted from four wobbles, and thus, the wobble sync
15 area 580 can detect a position most easily. Thus, the
information recording/reproducing apparatus according
to the present embodiment detects a position of the
wobble sync area 580, and then, carries out preparation
for a recording process, and starts recording. Thus,
20 it is necessary to arrange a start position of a
recording cluster 541 in a non-modulation area 590
immediately after the wobble sync area 580. FIG. 84
shows the contents of the allocation. The wobble sync
area 580 is arranged immediately after switching
25 position of a physical segment. The length of the
wobble sync area 580 is defined by 16 wobble cycles.
Further, after detecting the wobble sync area 580,
eight wobble cycles are required for preparation for
the recording process in consideration of a margin.
Therefore, as shown in FIG. 84, even in consideration
of a ransom shift, it is necessary that the start
5 position of the VFO area 522 which exists at the start
position of the recording cluster 541 is arranged
rearwardly by 24 wobbles or more from a switching
position of a physical segment.
As shown in FIG. 83, a recording process is
10 carried out many times in a duplicate site 591 at the
time of rewriting. When rewriting is repeated, a
physical shape of a wobble groove or a wobble land
changes (is degraded), and the wobble reproduction
signal amount is lowered. In the present embodiment,
15 as shown in FIG. 83 (f), a contrivance is made so that
a duplicate site 591 at the rewriting or at the time of
additional writing is recorded in the non-modulation
area 590 instead of arriving in the wobble sync area
580 or wobble address area 586. In the non-modulation
20 area 590, a predetermined wobble pattern (NPW) is
merely repeated. Thus, even if a wobble reproduction
signal amount is partially degraded, interpolation can
be carried out by utilizing the preceding and
succeeding wobble reproduction signals. In this way,
25 the position of the duplicate site 591 at the rewriting
or at the time of additional writing has been set so as
to be included in the non-modulation area 590. Thus,
there occurs advantageous effect that a stable wobble
detection signal from the wobble address information
610 can be guaranteed while preventing degradation of
the wobble reproduction signal amount due to the shape
5 degradation in the wobble sync area 580 or wobble
address area 586.
Now, FIG. 85 shows an embodiment of a method for
additionally writing a write-once type data recorded on
a write-once type information storage medium. A
10 position rearwardly of 24 wobbles is defined as a
writing start point from the boundary position of
physical segment blocks. With respect to data to be
newly additionally written, after a VFO area for
71 data bytes has been formed, a data area (data field)
15 in an ECC block is recorded. This writing start point
coincides with an end position of the buffer area 537
of recording data recorded immediately before the
writing. The backward position at which the expanded
guard field 528 has been formed by a length for eight
20 data bytes is obtained as a recording end position of
additional writing data (writing end point).
Therefore, in the case where data has been additionally
written, the data for eight data bytes is recorded to
be duplicated at a portion of expanded guard field 529
25 recorded just before and the VFO area to be newly
additionally written.
Chapter 8: Description of B Format
Optical disk specification of B format
FIG. 86 shows specification of an optical disk in
a B format using a blue violet laser light source. The
5 optical disks in the B format are classified into
rewritable-type (RE disk), read-only (ROM disk), and
write-once type (R disk). However, as shown in
FIG. 86, common specification other than standard data
transfer speed is defined in any type, facilitating the
10 achievement of a drive commonly compatible with a
different type. In a current DVD, two disk substrates
having thickness of 0.6 nm are adhered to each other.
In contrast, a structure is provided such that, in the
B format, a recording layer is provided on a disk
15 substrate having disk thickness of 1.1 nm, and the
recording layer is covered with a transparent cover
layer having thickness of 0.1 nm.
[Error correction system]
In the B format, there is employed an error
20 correction system capable of efficiently sensing a
burst error referred to as a "picket" code. A "picket"
is inserted into main data (user data) patterns at
predetermined intervals. The main data is protected by
strong, efficient Reed Solomon codes. A "picket" is
25 protected by second very strong, efficient Reed Solomon
codes other than the main data. During decoding, a
picket is first subjected to error correction.
Correction information can be used to estimate a
position of a burst error in the main data. As a
symbol of these positions, there is set a flag called
"erasure" utilized when correcting a code word of the
5 main data.
FIG. 87 shows a configuration of a "picket" code
(error correction block). An error correction block
(ECC block) of the B format is configured while the
user data of 64 Kbytes is defined in unit in the same
10 manner as in the H format. This data is protected by
very string, Reed Solomon codes LDC (long distance
codes).
An LCD is formed of 304 cord words. Each code
word is formed of 216 information symbols and 32 parity
15 symbols. Namely, a code word length has 248 (= 216 +
32) symbols. These code words are interleaved on a
2 x 2 basis in a vertical direction of ECC blocks,
configuring an ECC block of horizontal 152 (= 304/2)
bytes x vertical 496 (= 2 x 216 + 2 x 32) bytes.
20 A picket interleave length has 155 x 8 bytes
(there are eight correction series of control codes in
496 bytes), and a user data interleave length has 155 x
2 bytes. The 496 types in the vertical direction are
defined in units of recording on a 31 x 31 row basis.
25 With respect to the parity symbols of the main data,
two-groove parity symbols are provided as nests on a
one by one row basis.
In the B format, picket codes padded at
predetermined intervals have been employed for this ECC
block in a "columnar" shape. A burst error is sensed
by referring to a state of that error. Specifically,
5 four picket columns have been arranged at equal
intervals in one ECC block. An address is also
included in a "picket". A "picket" includes its unique
parity.
There is a need for correcting symbols in the
10 picket columns, and thus, the "pickets" in the right
three columns are subjected to error correction and
encoding by means of BIS (burst indicator subcode), and
is protected. This BIS is formed of 30 information
symbols and 32 parity symbols, and a code word length
15 has 62 symbols. It is found that very strong
correction capability exists from a ratio between
information symbols and parity symbols.
The BIS code word is interleaved and stored in
three picket columns each composed of 496 bytes. Here,
20 the number of parity symbols per code word which both
of LDS and BIS codes have is equal to 32 symbols. This
denotes that LDC and BIS can be decoded by one common
Reed Solomon decoder.
When data is decoded, first, a correcting process
25 of picket columns is carried out by means of the BIS.
In this manner, a burst error location is estimated,
and a flag called "erasure" is set in that location.
This flag is utilized when a code word of the main data
is corrected.
The information symbols protected by the BIS codes
forms additional data channels (side channels) other
5 than the main data. This side channel stores address
information. Prepared executive Reed Solomon codes
other than the main data are used for error correction
of address information. This code is formed of five
information symbols and four parity symbols. In this
10 manner, it has been possible to grasp an address at a
high speed and with a high reliability independent of
an error correction system of the main data.
[Address format]
In an RE disk, like a CD-R disk, a very thin
15 groove is engraved as a recording track like a spiral.
A recording mark is written into a protrusive portion
viewed in a laser light beam incident direction from
among the irregularities (on-groove recording).
Address information indicating an absolute
20 position on a disk is padded by slightly wobbling
(meandering or swinging) this groove like a CD-R disk
or the like. Digital data for modulating signal is
included, the digital data indicating "1" or "0" in the
shape or cycle of wobbling. FIG. 88 shows a wobble
25 system. A wobbling amplitude is slightly + 10 nm in a
disk radial direction. 56 wobbles (about 0.3 mm in
disk length) is obtained as one bit of address
information = ADIP unit (described later).
In order to write a fine recording mark without
almost any displacement, it is necessary to generate a
stable, precise recording clock signal. Therefore,
5 attention has been paid to a system in which a main
frequency component of the wobbles is single and a
groove is smoothly continuous. If the frequency is
single, a stable recording clock signal can be easily
generated from a wobble component sampled by a filter.
10 Timing information or address information is added
to a wobble on the basis of this single frequency.
"Modulation" is performed for the purpose of this
addition. For this modulation system, a system in
which an error is unlikely to occur is selected even if
15 a variety of variations specific to an optical disk
occur.
The following four variations of wobble signals
generated in an optical disk are summarized on a factor
by factor basis:
20 1) Disk noise: A variation in a surface shape
which occurs with a groove portion (surface roughness)
at the time of manufacturing, noise generated in a
recording film, and crosstalk noise leaks from recorded
data:
25 2) Wobble shift: A phenomenon that detection
sensitivity is lowered by a relative shift of a wobble
detection position from a normal position in a
recording/reproducing apparatus. This shift is likely
to occur immediately after seek operation.
3) Wobble beat: A crosstalk generated between a
track to be recorded and a wobble signal of the
5 adjacent track. In the case where the rotation control
system is CLV (constant linear velocity), this beating
occurs in the case where a shift occurs with an angle
frequency of the adjacent wobbles.
4) Defect: This is caused by a local defect due to
10 the dust or scratch of a disk surface.
In an RE disk, two different wobble modulation
systems are combined in the form such that a synergetic
effect is produced under a condition that high
durability is provided with respect to all of these
15 different four types of signal variations. In general,
this is because the durability relevant to four types
of signal variations which is hardly achieved by only
one type of modulation system can be obtained without
any side effect.
20 There are two systems: an MSK (minimum shift
keying system; and an STW (saw tooth wobble) system
(FIG. 89). The name of the STW comes from the fact
that its waveform is like a saw tooth shape.
In the RE disk, one bit of "0" or "1" is expressed
25 by a total of 56 wobbles. These 56 wobbles are
referred to as a unit, i.e., an ADIP (address inpre
groove) unit. When the ADIP unit is continuously read
out by 83 units, an ADIP word indicating one address is
obtained. The ADIP word is formed of: address
information having a 24-bit length; auxiliary data
having a 12-bit length; a reference (correction) area;
5 and error correction data. In the RE disk, three ADIP
words per one RUB (recording unit block, units of 64
Kbytes) for recording main data have been arranged.
The DIP unit consisting of 56 wobbles is greatly
divided into a first half and a latter half. The first
10 half whose wobble numbers range from 0 to 17 is an MSK
system; and the latter half whose wobble numbers range
from 18 to 55 is a STW system. These systems smoothly
communicate with a next ADIP unit. One bit can be
expressed by one ADIP unit. Depending on whether "0"
15 or "1" is set, first, in the first half, there is
changed a position of a wobble to which MSK system
modulation is applied; and, in the latter half, an
orientation of a saw tooth shape is changed, thereby
making discrimination.
20 The first-half portion of the MSK system is
divided into: a three-wobble area in which MSK
modulation has been further performed; and a mono-tone
wobble cos (cot) area. First, three wobbles from 0 to 2
always start from at any ADIP unit to which MSK
25 modulation has been applied. This is referred to as a
bit sync (identifier indicating start position of ADIP
unit).
After this identifier has been passed,
continuation of mono-tone wobbles is then obtained.
Then, data is indicated according to how many mono-tone
wobbles exist up to three wobbles which appear again
5 next and which has been subjected to MSK modulation.
Specifically, "0" is set in the case of 11 wobbles, and
"1" is set in the case of 9 wobbles. Data is
discriminated from each other by means of a shift of
two wobbles. The MSK system utilizes a local phase
10 change of a basic wave. In other words, an area in
which no phase change occurs is dominant. In the STW
system as well, this area is efficiently utilized as a
location in which a phase of a basic wave does not
change.
15 An area to which MSK modulation has been applied
has a three-wobble length. A phase is restored by
setting a frequency at 1.5 times with respect to a
mono-tone wobble at the first wobble; setting a
frequency equal to that of a mono-tone wobble at the
20 second wobble; and setting a frequency at 1.5 times
again at the third wobble. By doing this, the polarity
of the second (center) wobble is just inverted with
respect to the mono-tone wobble, and this inversion is
detected. At the first start point and at the third
25 end point, a phase is just fitted to a mono-tone
wobble. Therefore, smooth connection free from a
discontinuous portion can be made.
On the other hand, there are two types of
waveforms in the latter half STW system. One waveform
rapidly rises toward the disk outer periphery side and
returns in gentle inclination to the disk center side,
5 and the other waveform rises in gentle inclination, and
returns rapidly. The former indicates data "0", and
the latter indicates data "1". In one ADIP unit, the
same bit is indicated by using both of the MSK system
and the STW system, thereby improving data reliability.
10 When the STW system is mathematically expressed, a
secondary harmonic wave sin (2cot) whose amplitude is
1/4 is added to or subtracted from a basic wave cos
(cot) . However, even whichever of "0" and "1" the STW
system indicates, a zero cross point is identical to a
15 mono-tone wobble. Namely, its phase is not affected at
all when a clock signal is sampled from a basic wave
component common to a mono-tone portion in the MSK
system.
As described above, the MSK system and the STW
20 system function so as to compensate for weak points of
counterparts each other.
FIG. 90 shows an ADIP unit. A basic unit of an
address wobble forma is an ADIP unit. Each group of
56 NML (nominal wobble length) is referred to as an
25 ADIP unit. One NML is equal to 69 channel bits. An
ADIP unit of a different type is defined by inserting a
modulation wobble (MSK mark) into a specific position
contained in an ADIP unit (refer to FIG. 89). 83 ADIP
units are defined as one ADIP word. A minimum segment
of data recorded in a disk precisely coincides with
three continuous ADIP words. Each ADIP word includes
5 36 information bits (24 bits of which are address
information bits).
FIGS. 91 and 92 each show a configuration of an
ADIP word.
One ADIP word includes 15 nibbles, and nine
10 nibbles are information nibbles, as shown in FIG. 93.
Other nibbles are used for ADIP error correction.
15 nibbles configure a code word of Reed Solomon codes
[15, 9, 7] .
A code word is formed of nine information nibbles;
15 six information nibbles record address information; and
three information nibbles record auxiliary information
(for example, disk information).
Reed Solomon codes of [15, 9, 7] are nonsystematic,
and a hamming distance due to "informed
20 decoding" in knowledge in advance can be increased.
The "informed decoding" is such that all code words
have distance 7; all cod words of nibble ng has
distance 8 in common; and knowledge in advance relating
to ng increases a hamming distance. Nibble ng is
25 formed of an MSB of a layer index (three bits) and a
physical sector number. If nibble ng is known,
distance increases from 7 to 8.
FIG. 94 shows a track structure. A description
will be given here with respect to a track structure of
the first layer (which is distant from a laser light
source) and the second layer of a disk having a single-
5 sided double-layer structure. A groove is provided to
enable tracking in a push-pull system. Plural types of
track shapes are used. The first layer LQ and the
second layer L]_ are different from each other in
tracking direction. In the first layer, the left to
10 the right of the figure is a tracking direction. In
the second layer, the right to the left is a tracking
direction. The left side of the figure is a disk inner
periphery, and the right side is an outer periphery.
A BCA (burst cutting area) area formed of a first-
15 layer straight groove; a pre-recording area formed of
an HFM (High Frequency Modulated) groove; and a wobble
groove area in a rewritable area are equivalent to an
H-format lead-in area. A wobble groove area in a
second-layer rewritable area; a pre-recording area
20 formed of an HFM (High Frequency Modulated) groove; and
a BCA area formed of a straight groove are equivalent
to an H format lead-out area. However, in the H
format, the lead-in area and the lead-out area are
recorded in a pre-pit system instead of a groove
25 system. In the HFM groove, a phase is shifted in the
first and second layers so as not to produce an interlayer
crosstalk.
FIG. 95 shows a recording frame. As shown in
FIG. 87, the user data is recorded on 64 by 64 Kbytes
basis. Each row of the ECC cluster is converted into
the recording frame by adding frame sync bits and DC
5 control units. The stream of 1240 bits (155 bytes) in
each row is converted as follows. Data of 25 bits is
arranged at the beginning of the 1240-bit stream, and
the subsequent data is divided into data of 45 bits; a
frame sync code of 20 bits is added before data of
10 25 bits; one DC control bit is added after data of
25 bits; and one DC control bit is added after data of
45 bits similarly. A block including data of the first
2 bits is defined as DC control block #0, and the
subsequent data of 45 bits and one DC control bit are
15 defined as DC control blocks #1, #2, ... #27. 496
recording frames are referred to as a physical cluster.
A recording frame is subjected to 1-7PP modulation
at a rate of 2/3. A modulation rule is applied to 1268
bits excluding the first frame sync code; 1902 channel
20 bits are formed; and a frame sync code of 30 bits is
added at the beginning of the entirety. That is, 1932
channel bits (= 28 NML) are configured. A channel bit
is subjected to NRZI modulation, and the modulated bit
is recorded in a disk.
25 Frame sync code structure
Each physical cluster includes 16 address units.
Each address unit includes 31 recording frames. Each
recording frame starts from a frame sync code of 30
channel bits. The first 24 bits of frame sync code
violates a 1-7PP modulation rule (including a length
which is twice of 91). Ihe 1-7PP modulation rule uses
5 a (1, 7)PLL modulation system to carry out Parity
Preserve/Prohibit RMTR (repeated minimum transition run
length). Parity Preserve makes control of a so called
DC (direct current) component of a code (decreases a DC
component of a code). The remaining six bits of frame
10 sync code changes, and identifies seven frame sync
codes FSO, FS1, ... FS6. These six-bit signs are
selected so that a distance relating to a deflection
amount is equal to or greater than 2.
Seven frame sync codes make it possible to obtain
15 more detailed positional information than only 16
address units. Of course, it is insufficient to
identify 31 recording frames merely by seven different
frame sync codes. Therefore, from 31 recording frames,
seven frame sync sequences are selected so that each
20 frame can be identified by using a combination between
one's own frame sync codes and a frame sync code of
each of four preceding frames.
FIGS. 96A and 96B each show a structure of a
recording unit block RUB. A recording unit is referred
25 to as a RUB. As shown in FIG. 96A, the RUB is formed
of: 40-wobble data run-in; a physical cluster of 496 x
28 wobbles; and 16-wobble data run-out. Data run-in
and data run-out enables sufficient data buffering in
order to facilitate completely random overwriting. The
RUB may be recorded on a one by one basis or a
plurality of RUBs are continuously recorded as shown in
5 FIG. 96B.
Data run-in is mainly formed of a repetition
pattern of 3T/3T/2T/2T/5T/5T, and two frame sync codes
(FS4 and FS6) are spaced from each other by 40cbs as an
indicator indicating a start position of a next
10 recording unit block.
The data run-out starts at FSO, follows a
9T/9T/9T/9T/9T/9T pattern which indicates the end of
data after FSO, and follows a repetition pattern mainly
formed of 3T/3T/2T/2T/5T/5T.
15 FIG. 97 shows a structure of data run-in and data
run-out.
FIG. 98 is a view showing allocation of data
relating to a wobble address. A physical cluster is
formed of 496 frames. A total of 56 wobbles (NWLs) of
20 data run-in and data run-out are 2 x 28 wobbles, and
correspond to two recording frames.
One RUB = 496 + 2 = 498 recording frames
One ADIP unit = 56 NWLs = Two recording frames
83 ADIP units = One ADIP word (including one ADIP
25 address)
Three ADIP words = 3 x 83 ADIP units
Three ADIP words = 3 x 83 x 2 = 498 recording
frames
When data is recorded in a write-once disk, it is
necessary to continuously record next data in already
5 recorded data. If a gap occurs with data, reproduction
cannot be carried out. Then, in order to record
(overwrite) the first data run-in of the succeeding
recording frame to be overlapped on the last data runout
of the preceding recording frame, three guard areas
10 are arranged at the end of the data run-out area, as
shown in FIGS. 99A and 99B. FIG. 99A shows a case in
which only one physical cluster is recorded; and
FIG. 99B shows a case in which a plurality of physical
clusters are continuously recorded, wherein three guard
15 areas are provided only after run-out of the last
cluster. Thus, each of the recording units recorded
along, or alternatively, a plurality of recording unit
blocks continuously recorded are terminated in three
guard areas. These three guard areas guarantees that
20 an unrecorded area does not exist between the two
recording unit blocks.
Now, a description will be given with respect to
reproduction durability of a write-once type
information storage medium according to an embodiment
25 of the present invention. This storage medium includes
a transparent resin substrate formed in a disk shape,
the substrate being made of a synthetic resin material
such as polycarbonate, for example. On this
transparent resin substrate, a groove is formed in a
concentric shape or in a spiral shape. This
transparent resin substrate can be manufactured by
5 injection molding using a stamper.
In addition, on this transparent resin substrate,
a recording film including an organic dye is formed so
as to fill its groove. An organic dye forming this
recording film is used such that its maximum absorption
10 wavelength area is shifted to a longer wavelength side
than a recording wavelength (405 nm). In addition,
absorption is not eliminated in a recording wavelength
area, and a design has been made so as to have
substantial light absorption.
15 In this manner, in the case where focusing or
tracking is carried out on a track before information
recording by means of a recording laser light beam, a
low light reflectivity is obtained. A dye decomposing
reaction is caused by the laser light beam, and the
20 light absorbance is lowered, and thereby the light
reflectivity of a recording mark portion rises. Thus,
there are achieved so called a low-to-high (L to H)
characteristic that the light reflectivity of the
recording mark portion formed by irradiating the laser
25 light beam is higher than that before the laser light
irradiation.
In addition, a transparent resin substrate, and,
in particular, a groove bottom may be deformed due to a
heat generated. In this case, a phase difference may
occur with reflection light.
The above-described organic dye is liquefied by
5 being solved in a solvent, and the liquefied dye can be
easily applied onto a transparent resin substrate
surface in accordance with a spin coat technique. In
this case, film thickness can be managed with high
precision by controlling a dilution rate based on a
10 solvent or a rotation speed at the time of spin
coating.
The organic dye consists of a dye portion and an
counter-ion (anion) portion. As the dye portion, a
cyanine dye or a styryl dye and the like can be used.
15 In particular, the cyanine dye and the styryl dye are
preferred because absorbance relative to a recording
wavelength is easily controlled.
Referring to FIGS. 102A to 102E and 101A to 101C,
a description will be given with respect to a method
20 for producing a disk stamper for a write-once type
storage medium.
As shown in FIG. 102A, there is prepared: a
silicon wafer 2011 for manufacturing a semiconductor,
the wafer being formed in a disk shape to have a
25 diameter of 200 nm and thickness of 0.725 mm.
This silicon wafer 2011 is immersed for 5 minutes
in a mixture solution of a thermal concentrated
sulfuric acid and hydrogen peroxide water (solution
temperature 100°C). Next, the silicon wafer 2011 is
rinsed by immersing it in ultra-pure water, and the
rinsed wafer is washed with ultrasound waves; the
5 washed wafer is immersed in a 70°C ultra-pure water
tank, and the immersed wafer is dried by gradually
pulling it up.
Then, as shown in FIG. 102B, an electron beam
resist film 2012 is formed on a surface of the silicon
10 wafer 2011. This electron beam resist film 2012 is
formed by spin-coating a resist solution obtained by
mixing and stirring an electron beam resist (ZEP520A7
available from ZEON Corporation) by 86.2% by weight
with respect to an anisole solvent (ZEP-A available
15 from ZEON Corporation) on a surface of the silicon
wafer 2011.
In addition, in a spin coating condition, the
silicon wafer 2011 is vacuum-chucked on a spin table; a
resist solution is dropped at the center part of the
20 silicon wafer 2011 via a 0.1 micron filter while
rotation of the spin table stops; and then, the spin
table is rotated at 2500 rpm.
Then, as shown in FIG. 102C, a groove 2013 is
formed in the electron beam resist film 2012. This is
25 accomplished by putting the silicon wafer 2011 coated
with the electron beam resist film 2012 in a vacuum
tank serving as an electron beam cutting machine;
carrying out evacuation up to 10~5 Pa; and then,
rotating the silicon wafer 2011; irradiating an
electron beam from an electron gun 2014 to the electron
beam resist film 2012; and carrying out electron-beam
5 recording of a concentric or spiral groove pattern.
A groove pattern recording condition is such that
an electron beam acceleration voltage is 50 kV; a beam
current is 120 nA; a beam diameter is 110 nm; and a
recording beam linear speed is 1.1 m/sec. In a
10 recording area of the groove 2013, the radius of the
silicon wafer 2011 ranges from 23 mm to 59 mm.
Then, the silicon wafer 2011 on which the groove
13 has been recorded is removed from the inside of the
vacuum tank serving as the electron beam cutting
15 machine, and dip developing is carried out while the
removed silicon wafer is immersed in an organic
developing solution 2016 contained in an immersing tank
2015, as shown in FIG. 102D, thereby forming a resist
pattern of the groove 2013.
20 Next, DC sputtering of an Ni film is carried out,
and thereby an Ni thin film 2017 is formed and
electrically conducted onto the above-described resist
pattern surface, as shown in FIG. 102E.
Then, as shown in FIG. 101A, Ni electric casting
25 is carried out on the Ni thin film 2017, forming an Niplated
layer 2018 having thickness of 247 Then, as
shown in FIG. 101B, the Ni-plated layer 2018 is
released, and spin-coated, and then, the residual resin
is released from a surface by means of oxygen RIE.
Then, as shown in FIG. 101C, the Ni-plated layer 2018
is coated with a protective film; a back face side
5 thereof is polished; an inner diameter and an outer
diameter are processed; and a disk stamper 2019 is
produced.
Next, a write-once type optical disk is produced
by using this disk stamper 2019. That is, as shown in
10 FIG. 100A, by using the disk stamper 2019, injection
molding is carried out by using an injection molding
device SD40 available from Sumitomo Heavy Industries
Co., Ltd, thereby duplicating a transparent disk
substrate 2020 made of polycarbonate having thickness
15 of 0.6 mm as shown in FIG. 101B. A groove 2021 is, of
course, formed on this disk substrate 2020.
Then, as shown in FIG. 100C, by using a dispenser
2022 having a nozzle diameter of 21G, an organic dye
solution 2023 described later obtained by dissolving an
20 organic dye in a solvent is dropped on a surface of the
disk substrate 2020 on which the groove 2021 is formed.
Next, by rotationally controlling the disk substrate
2020, as shown in FIG. 100D, the groove 2021 is filled
with the organic dye solution 2023, and a recording
25 film 2024 is formed.
A spin coat condition of this recording film 2024,
as shown in FIG. 103, is such that, first, the disk
substrate 2020 is rotationally driven from an inactive
state to 300 rpm within 1 second, and the organic dye
solution 2023 is coated by means of the dispenser 2022
while this state is maintained for 8 seconds. Next,
5 the rotation frequency of the disk substrate 2020 is
increased to 1800 rpm within 2 seconds, and this state
is maintained for 15 seconds. Then, the rotation
frequency of the disk substrate 2020 is increased to
3000 rpm within 2 seconds, and this state is maintained
10 for 3 seconds.
The film thickness of the recording film 2024 can
be controlled by controlling the rotation speed at a
second stage. More specifically, the film thickness of
the recording film 2024 can be increased by setting the
15 rotation speed at the second stage at a low speed.
Next, the disk substrate 2020 coated with the
recording film 2024 is baked at 80°C for 30 seconds by
using a clean oven, and a 100 nm metal film 2025 is
sputtered on the recording film 2024, as shown in
20 FIG. 100E. An Ag alloy including 1% of Bi in Ag is
used as this metal film 2025.
Then, as shown in FIG. 100F, an ultraviolet-ray
curing type resin 2026 is spin-coated on the metal film
2025, and a disk substrate 2027 made of polycarbonate
25 having thickness of 0.6 mm is adhered onto the spincoated
resin, and thereby a write-once type optical
disk (R disk) 2028 including an organic dye in the
recording film 2024 is produced.
Here, in the write-once type optical disk 2028
produced as described above, a laser light beam for
recording and reproduction by an optical head 2029 is
5 made incident from a face opposite to a face coated
with the recording film 2024 of the disk substrate
2020, as shown in FIG. 104.
In this case, a bottom face 2021a of the groove
2021 formed on the disk substrate 2020 and a land 2020
10 sandwiched between the adjacent grooves 2021 are
obtained as information recording tracks. The
recording track made of the bottom face 2021a of the
groove 2021 is referred to as a groove track Gt, and
the recording track made of the land 2030 is referred
15 to as a land track Lt.
In addition, a height difference between a face of
the groove track Gt and a face of the land track Lt is
referred to as a groove depth Gh. Further, a width of
the groove track Gt viewed from a height which is
20 almost 1/2 of the groove depth Gh is referred to as a
groove width Gw, and a width of the land track Lt
viewed from a height which is almost 1/2 of the groove
depth Gh is referred to as a land width Lw.
Now, a description will be given with respect to
25 generation of the above-described organic dye solution
2023. This organic dye solution 2023 is used as a
solution having a solution concentration of 1.2% by
weight obtained by dissolving organic dye powders of
1.2g in 100 nm of TFP. A solution condition for a
solvent is such that dye powders are put in the
solvent, and ultrasound waves are applied for
5 30 minutes.
By using the organic dye, a write-once optical
disk 2028 is produced by the above-described method,
and recording and reproduction are carried out in these
groove tracks Gt, thereby carrying out an evaluation
10 test. As an evaluation device, an optical disk
evaluation device available from PULSTEC Co., Ltd is
used.
A testing condition is such that an objective lens
aperture NA of an optical head is 0.65; a wavelength of
15 a laser light beam for recording and reproduction is
405 nm; and a linear velocity during recording and
reproduction is 6.61 m/sec. A recording signal is 8-12
modulated random data, and is a waveform recorded by
predetermined recording power and two types of bias
20 powers 1 and 2 as shown in FIG. 105.
In addition, track pitches are 400 nm; a groove
width Gw is defied as "1.2" with respect to a land
width Lw "I"; a wobble amplitude of the groove track Gt
is 14 nm; and the groove depth Gh is 60 nm. Wobble
25 phase modulation is used to record address information
using wobbles.
Here, three types of evaluation characteristics
are measured including: a carrier noise ratio CNR of a
reproduction signal; an SN ratio during partial
response (partial response signal to noise ratio:
PRSNR); and a simulated bit error rate SbER. PRSNR
5 defining and measuring techniques are described in a
book which can be purchased from DVD Format Logo
Licensing Co., Ltd. This is a part of Annex H of DVD
Specifications for High Density Read-Only Disc PART 1
Physical Specifications Version 1.0. It is preferable
10 that the PRSNR be 15 or more. The SbER defining and
measuring techniques are described in a book which can
be purchased from DVD Format Logo Licensing Co., Ltd.
This is a part of Annex H of DVD Specifications for
High Density Read-Only Disc PART 1 Physical
15 Specifications Version 1.0. It is preferable that the
SbER be 5.0 x 10~5 or less. The PRSNR and SbER are
measured in a state in which information is recorded in
the adjacent tracks.
As evaluation characteristics, three types of
20 light reflectivity, SbER, and PRSNR are measured. A
light reflectivity defining and measuring techniques
are described in a book which can be purchases from DVD
Format Logo Licensing Co., Ltd. This is a part of
Annex D of DVD Specifications for High Density Read-
25 Only Disc PART 1 Physical Specifications Version 1.0.
The reflectivity corresponds to I11H level after
recording. It is preferable that the reflectivity
range from 14% to 28% in order to obtain reproduction
light durability of 1,000,000 times or more.
In addition, in the case where management
information (system lead-in) is inserted into a certain
5 portion of a disk, for example, into the innermost
peripheral area, the most advantageous effect can be
attained in this Low-to-High recording disk. With
respect to management information, pit arrays identical
to those on a ROM disk substrate are formed on a disk
10 substrate. What is recorded as a pit array is
management information such as whether the disk is a
read-only type or write-once type, or rewritable type;
what recording and reproducing wavelength is, whether
the recording film type is Low-to-High or High-to-Low,
15 and what a recording data capacity is. The track
pitches of a groove of a recording data area are
selected as 400 nm or in the range of 320 nm to 300 nm.
Advantageously, the track pitches of the pit array in
this management information area is formed to be wider
20 than the above track pitches, and data bit pitches of
pits are larger than that of the recording data area,
thereby facilitating reproduction and making it
possible to easily judge management information. The
Low-to-High disk is uniform in signal level position
25 between a system lead-in area and a data area, and
drive reproduction is made easy.
Now, a description will be given with respect to a
test result relating to reproduction durability count
in the case where a mark recorded in an optical disk
using an organic dye material according to the present
invention for a recording material has been
5 continuously reproduced by a blue laser light beam
pickup. Here, testing has been carried out with
respect to 5 types of organic dye materials.
A first material is dye "A" which is an organic
metal complex simplex, and a general structural formula
10 of Al which is an example of the dye is shown in
FIG. 106. Cu, Zn, Ni, Co, Fe, Sc, Ti, V, Cr, Mn, Al,
Gd, and Y or the like are mainly used as M. Cu is the
best in reproduction light durability.
As Rl to R5, there are used CH3, C2H5, H,
15 CH2N(CH3)2, SCH3, N02, Cl, S02NHCH3, CN, and CH30CH2 or
the like without being limited thereto. In particular,
in the case where Cl has been added, the best
reproduction light durability is obtained.
In an example Al of dye "A", M is Cu; Rl is CH3;
20 R2 is CH3; R3 is Cti^; R4 is Cl; and R5 is Cl.
A second material is dye B which is an organic
metal complex simplex having another structure, and a
general structural formula of Bl which is an example of
the dye is shown in FIG. 107. Cu, Zn, Ni, Co, Fe, Sc,
25 Ti, V, Cr, Mn, Al, Gd, and Y or the like are mainly
used as M. Cu is the best in reproduction light
durability.
As Rl to R5, there are used CH3, C2H5, H, CH2N
(CH3) 2i SCH3, N02, Cl, S02NHCH3, CN, and CH3OCH2 or
the like without being limited thereto. In particular,
in the case where Cl has been added, the best
5 reproduction light durability is obtained.
In an example Bl of dye B, M is Cu; Rl is C2H5; R2
is CH3; R3 is C2H5,- R4 is SCH3; and R5 is Cl.
Bl is better than Al in PRSNR and SbER when it is
used for an optical disk; and is better in recording
10 and reproducing characteristics such as large degree of
modulation and high reflectivity.
A third dye is a mixture dye made of an organic
metal complex cation and anion U composed of cation and
an organic metal complex anion; an organic metal
15 complex cation and anion W composed of cation and an
organic metal complex anion; and an organic metal
complex simplex Y, and is a mixture of dye Ul, dye Wl,
and dye Y2. An azo phthalocyanine metal complex has
been used as Y. A general structural formula of U, a
20 general structural formula of W, and a general
structural formula of Y are shown in FIG. 108,
FIG. 109, and FIG. 110, respectively.
Here, a cation portion in FIG. 108 is a
monomethine cyanine dye, and an anion portion in
25 FIG. 108 is an organic metal complex.
In addition, with respect to the above-described
monomethine cyanine dye, Z]_ and Z2 represent aromatic
rings which are identical to or different from each
other, and these aromatic rings may have substituents.
Y]_]_ and Y]_2 each represent a carbon atom or a hetero
atom independently. R]_]_ and R]_2 each represent an
5 aliphatic hydrocarbon group, and these aliphatic
hydrocarbon groups may have substituents. RIS? ^14?
R]_5, and R]_g each represent a hydrogen atom or an
appropriate substituent independently. In the case
where ¥]_]_ and Y]_2 are hetero atoms, part or all of R]_3,
10 R14' R15' and Ri6 do/does not exist.
In addition, in the above-described organic metal
complex, A and A1 represent heterocyclic groups which
are identical to or different from each other, the
groups each containing one or a plurality of hetero
15 atoms selected from a nitrogen atom, an oxygen atom, a
sulfur atom, a selenium atom, and a tellurium atom.
R2i to R24 each represent a hydrogen atom or a
substituent independently. ¥21 and ¥22 each represent
hetero atoms which are identical to or different from
20 each other, the atoms each being selected from elements
of a sixteenth family in the periodic table.
Monomethine cyanine dyes used in the present
embodiment can include dyes obtained when cyclic
nucleuses such as an imidazoline ring; an imidazole
25 ring; a benzoimidazole ring; an a-naphthoimidazole
ring; a p-naphthoimidazole ring; an indole ring; an
isoindole ring; an indorenin ring; an isoindorenin
ring; a benzo indorenin ring; a pyridino indorenin
ring; an oxazolline ring; an ozazole ring; an
isoozazole ring; a benzooxazole ring; pyridino oxazole
ring; an a-naphtooxazole ring; a p-naphthoozazole ring;
5 a serenazoline ring; a serenazole ring; a
benzoserenazole ring; an a-naphthoserenazole resin; a
p-naphthoserenazole ring; a thiazoline ring; a thiazole
ring; an isothiazole ring; a benzothiazole ring; an xnaphthothiazole
ring; a p-naphthothiazole ring; a
10 terrazoline ring; a terrazole resin; a benzoterrazole
ring; an a-naphthoterrazole ring; a p-naphthoterrazole
ring; and further, an acrydine ring; an antracen ring;
an isoquinoline ring; an isopyrole ring; an
imidanoxaline ring; an indandione ring; an indazole
15 ring; an indaline ring; an oxadiazole ring; a carbazole
ring: a xantene ring; a quinazoline ring; a quinoxaline
ring; a quinoline ring; a chroman ring; a cyclohexane
dione ring; a cyclopentane dione ring; a cinnoline
ring; a thiodiazole ring; a thiooxazolidone ring; a
20 thiophene ring; a thionaphthene ring; a thiobarbizuric
acid ring; a thiohidantoin ring; a tetrazole resin; a
triazine ring; a naphthalene ring; a naphthyridine
ring; a piperadine ring; a pyradine ring; a pyrazole
ring; a pyrazoline ring; a pyrazolidine ring; a
25 pyrazolone ring; a pyrane ring; a pyridine ring; a
pyridazine ring; a pyrimidine ring; a pyrilium ring; a
pyrolidine ring; a pyroline ring; a pyrol ring; a
phenedine ring; a phenantholidine ring; a phenanthorene
ring; a phenanthoroline ring; a phthaladine ring; a
putheridine ring; a phrazane ring; a phrane ring; a
purine ring; a benzene ring: a benzooxadine ring; a
5 benzopirane ring; a morpholine ring; and a rhodaline
ring or the like, which are identical to or different
from each other, having one or a plurality of
substituents, are bonded on both ends of a monomethine
chain which may have one or a plurality of
10 substituents.
In addition, through general formulas of the
monomethine cyanine dye, Zl to Z3, for example,
represent aromatic rings such as a benzene ring, a
naphthalene ring, a pyridine ring, a quinoline ring;
15 and a quinoxaline ring or the like, and these aromatic
rings may have one or a plurality of substituents. The
substituents, for example, can include: aliphatic
hydrocarbon groups such as a methyl group, a trifluoro
methyl group, an ethyl group, a propyl group, an
20 isopropyl group, a butyl group, an isobutyl group, a
sec-butyl group, a tert-butyl group, a pentyl group, an
isopentyl group, a neopentyl group, a tert-pentyl
group, a 1-methyl pentyl group, a 2-methyl pentyl
group, a hexyl group, an isohexyl group, a 5-methyl
25 hexyl group, a heptyl group, and an octyl group;
cycloaliphatic hydrocarbon groups such as a cyclopropyl
group, a cyclobutyl group, a cyclopentyl group, and a
cyclohexyl group; aromatic hydrocarbon groups such as a
phenyl group, a biphenyl group, an o-tryl group, an
m-tryl group, a p-tryl group, a xyryl group, a mecityl
group, an o-cumenyl group, an m-cumenyl group, a
5 p-cumenyl group; ether groups such as a methoxy group,
a trfluoro methoxy group, an ethoxy group, a propoxy
group, an isopropoxy group, a buthoxy group, a secbuthoxy
group, a tert-buthoxy group, a pentyloxy group,
a phenoxy group, a benzoir oxy group; ester groups such
10 as a methoxycarbonyl group, a trifluoro methoxycarbonyl
group, an ethoxycarbonyl group, a propoxycarbonyl
group, an acetoxy group, and a benzoir oxy group;
halogen groups such as a fluoro group, a chloro group,
a bromo group, and an iodine group; thio groups such as
15 a metylthio group, an ethylthio group, propylthio
group, butylthio group, and a phenylthio group;
sulfurmoyl groups such as a methyl sulfurmoyl group, a
dimethyl sulfurmoyl group, an ethyl sulfurmoyl, a
diethyl sulfurmoyl group, a propyl sulfurmoyl group, a
20 dipropyl sulfurmoyl group, a butyl sulfurmoyl group,
and a dibutyl sulfurmoyl group; amino groups such as a
first class amino group, a methyl amino group, a
dimethyl amino group, an ethyl amino group, a diethyl
amino group, a propyl amino group, a dipropyl amino
25 group, an isopropyl amino group, a diisopropyl amino
group, a butyl amino group, a dibutyl amino group, and
a pyperidino group; carbamoyl groups such as a methyl
carbamoyl group, a dimethyl carbamoyl group, an ethyl
carbamoyl group, a diethyl carbamoyl group, a propyl
carbamoyl group, and a dipropyl carbamoyl group; and
further, a hydroxy group, a carboxy group, a cyano
5 group, a nitro group, a sulfino group, a sulfo group,
and a mecyl group or the like. In a general formula,
Z]_ and Z2 may be identical to or differential from each
other.
¥]_]_ and Y]_2 in a general formula of a monomethine
10 cyanine dye each represent a carbon atom or a hetero
atom. Hetero atoms, for example, can include atoms of
a fifteenth family and a sixteenth family in the
periodic table such as a nitrogen atom, an oxygen atom,
a sulfur atom, a selenium atom, or a tellurium atom.
15 The carbon atoms in ¥]_]_ and Y]_2 maY be an atom group
consisting essentially of two carbon atoms such as an
ethylene group and a vinylene group, for example. ¥]_]_
and Y]_2 in the general formula of the monomethine
cyanine dye may be identical to or different from each
20 other.
Rll' R12' and RIB in the general formula of the
monomethine cyanine dye represent aliphatic hydrocarbon
groups. Example of the aliphatic hydrocarbon groups
can include: a methyl group; an ethyl group; a propyl
25 group; an isopropyl group; an isopropenyl group; a
1-propenyl group; a 2-propenyl group; a butyl group; an
isobutyl group; a sec-butyl group; a tert-butyl group;
a 2-butenyl group; a 1, 3-butadinyl group; a pentyl
group; an isopentyl group; a neopentyl group; a tertpentenyl
group; a 1-methyl pentyl group; a 2-methyl
pentyl group; a 2-pentenyl group; a hexyl group; an
5 isohexyl group; a 5-methyl hexyl group; a heptyl group,
and an octyl group or the like. The aliphatic
hydrocarbon groups may have one or a plurality of
substituents similar to those in Z]_ to Z.
In addition, R]_1 and R]_2 in the general formula of
10 the monomethine cyanine dye may be identical to or
different from each other.
R]_3 to R]_g in the general formula of the
monomethine cyanine dye each represent hydrogen atoms
or proper substituents independently in individual
15 general formulas. The substituents, for example,
include: aliphatic hydrocarbon groups such as a methyl
group, a trifluoro methyl group, an ethyl group, a
propyl group, an isopropyl group, a butyl group, an
isobutyl group, a sec-butyl group, a tert-butyl group,
20 a pentyl group, an isopentyl group, a neopentyl group;
a tert-pentyl group, a 1-methyl pentyl group, a
2-methyl pentyl group, a hexyl group, an isohexyl
group, a 5-methyl hexyl group, a heptyl group and a
octyl group; ether groups such as a methoxy group, a
25 trifluoro methoxy group, an ethoxy group, a propoxy
group, buthoxy group, a tert-buthoxy group, a pentyl
oxy group, a phenoxy group, and a benxoir oxy group;
halogen groups such as a fluoro group, a chloro group,
a bromo group, and an iodine group; and further, a
hydroxy group; a carboxy group; a cyano group; and a
nitro group or the like. In the general formula of the
5 monomethine cyanine dye, in the case where ¥]_]_ and Y]_2
are hetero atoms, part or all of R]_3 to R]_g in Z]_ and
Z2 do/does not exist.
In addition, in the general formula of the abovedescribed
azo metal complex, A and A1 each represent
10 heterocyclic groups of five rings to ten rings such as
a furyl group, a thienyl group, a pyroryl group, a
pyridyl group, a pypelidino group, a pypelizyl group, a
quinoryl group, and an isooxazoryl group, for example,
which are identical to or different from each other and
15 contain one or a plurality of hetero atoms selected
from among a nitrogen atom, an oxygen atom, a sulfur
atom, a selenium atom, and a tellurium atom. These
heterocyclic groups, for example, may have one or a
plurality of aliphatic hydrocarbon groups such as a
20 methyl group, a trifluoro methyl group, an ethyl group,
a propyl group, an isopropyl group, a butyl group, an
isobutyl group, a sec-butyl group, a tert-butyl group,
a pentyl group, an isopentyl group, a neopentyl group,
a tert-pentyl group, a 1-methyl pentyl group, a
25 2-methyl pentyl group, a hexyl group, an isohexyl
group, and a 5-methyl hexyl group; ester groups such as
a methoxy carbonyl group, a trifluoro methoxy carbonyl
group, an ethoxy carbonyl group, a propoxy carbonyl
group, an acetoxy group, a triflyoro acetoxy group, and
benzoir oxy group; aromatic hydrocarbon groups such as
a phenyl group, a biphenyl group, an o-tryl group, an
5 m-tryl group, a p-tryl group, an o-cumenyl group, an
m-cumenyl group, a p-cumenyl group, a xyryl group, a
mecityl group, a styryl group, a cinnamoyl group, and a
naphtyl group; and further, substituents such as a
carboxyl group, a hydroxy group, a cyano group, and a
10 nitro group.
An azo compound configuring an azo-based organic
metal complex represented by a general formula can be
obtained in accordance with a normal technique by
reacting a diazonium salt having R2l> ^22 or R23' R24
15 which corresponds to the general formula with
heterocyclic compounds such as an isooxazolone
compound, an oxazolone compound, a thionaphthene
compound, a pyrazolone compound, a barbizuric acid
compound, a hydantoin compound, and a rhodanine
20 compound or the like, for example, having an active
methylene group adjacent to a carbonyl group in a
molecule. ¥21 and ¥22 each represent hetero atoms
which are identical to or different from each other,
the atoms being selected from elements of the sixteenth
25 family in the periodic table such as an oxygen atom, a
sulfur atom, a selenium atom, and a tellurium atom, for
example.
The azo metal complex represented by the general
formula is generally used in a mode in which one or a
plurality of metal complexes are oriented at a metal
(center atom). Examples of metal elements serving as
5 the center atoms, for example, can include scandium,
yttrium, titanium, zirconium, hafnium, vanadium,
niobium, tantalum, chromium, molybdenum, tungsten,
manganese, technetium, rhenium, iron, lutenium, osmium,
cobalt, rhodium, iridium, nickel, palladium, platinum,
10 copper, silver, gold, zinc, cadmium, and mercury or the
like. In particular, cobalt is preferred. X^ in the
general formula represents a proper anodic ion
including an onium ion such as alkyl ammonium ion, a
pyridinium ion, and quinolinium ion, for example.
15 As M of the azo phthalocyanine complex Y, there is
used any of Cu, Ni, Al, Zn, Y, Co, Fe, Sc, Ti, V, Cr,
and Mn. In particular, Cu is the best in reproduction
light durability.
As R, there is used CH3, C25 H CH2N(CH3)2'
20 SCH3, NC2, Cl, SC2NHCH3, CN, CH30CH2, and SC^H or the
like without being limited thereto. In particular, in
the case where Cl is added, the reproduction light
durability is good.
Structural formulas of Ul which is an example of
25 U, Wl which is an example of W, and Y2 are shown in
FIG. Ill and FIG. 112.
With respect to Y2 which is an example of Y, Ni is
selected as M, and N02 is selected as R.
A mixture ratio by weight of U, W, and Y is 1.0 :
2.0 : 0.15.
If a formazane metal complex V is used instead of
5 Y2, a similar dye is obtained. A structural formula of
V is shown in FIG. 113.
A fourth dye is a mixture dye of an organic metal
complex B; an organic metal complex cation and anion W
composed of cation and an organic metal complex anion;
10 and an organic metal complex simplex Y, and is a
mixture of dye Bl, dye W2, and dye Yl. An axo
phthalocyanine metal complex was used as Y. A general
structural formula of W2 which is an example of W is
shown in FIG. 114.
15 In Yl which is an example of Y, Cu is selected as
M, and Cl is selected as R.
A mixture ratio by weight of B, W, and Y is 0.7 :
0.3 : 0.15.
A fifth dye is a mixture dye of an organic metal
20 complex cation and anion U composed of cation and an
organic metal complex anion; an organic metal complex
cation and anion W composed of cation and an organic
metal complex anion; and an organic metal complex
simplex Y, and is a mixture of dye Ul, dye Wl, and dye
25 Y2. An azo phthalocyanine metal complex has been used
as Y. A mixture ratio by weight of U, W, and Y is
1.0 : 2.0 : 0.15.
In addition to these examples, as an organic metal
complex anion and cation, there can be used general
structural formulas such as WW shown in FIG. 115; WWW
shown in FIG. 116; and WWWW shown in FIG. 117. As an
5 example of WW, WW1 is shown in FIG. 118; as an example
of WWW, WWW1 is shown in FIG. 119; and as examples of
WWWW, WWWW1 and WWWW2 are shown in FIG. 120 and
FIG. 121. In the general formula of the organic metal
complexes WW, WWW, and WWWW, A an A' each represent
10 heterocyclic groups of five to ten rings such as a
furyl group, a thienyl group, a pyrrolyl group, a
pyridyl group, a pyperidino group, pyperidyl group, a
quinoryl group, and isooxazoryl group, for example,
which are identical to or different from each other,
15 the groups each containing one or a plurality of hetero
atoms selected from a nitrogen atom, an oxygen atom, a
sulfur atom, a selenium atom, and a tellurium atom.
These heterocyclic groups, for example, may have one or
a plurality of aliphatic hydrocarbon groups such as a
20 methyl group, a trifluoro methyl group, an ethyl group,
a propyl group, an isopropyl group, a butyl group, an
isobutyl group, a sec-butyl group, a tert-butyl group,
a pentyl group, an isopentyl group, a neopentyl group;
a tert-pentyl group, a 1-methyl pentyl group, a 2-
25 methyl pentyl group, a hexyl group, an isohexyl group,
and a 5-methyl hexyl group; ester groups such as a
methoxy carbonyl group, a trifluoro methoxy carbonyl
group, an ethoxy carbonyl group, a propoxy carbonyl
group, an acetoxy group, a trifluoro acetoxy group, and
benzoir oxy group; aromatic hydrocarbon groups such as
a phenyl group, a biphenyl group, an o-tryl group, an
5 m-tryl group, a p-tryl group, an o-cumenyl group, an
m-cumenyl group, a p-cumenyl group, a xyryl group, a
mecityl group, a styryl group, a cinnamoyl group, and a
naphtyl group; and further, substituents such as a
carboxy group, a hydroxy group, a cyano group, and a
10 nitro group.
A compound configuring an organic metal complex
represented by a general formula can be obtained in
accordance with a normal technique by reacting a
diazonium salt having R, R21, R32, R33, R34, R41, and
15 R42 which correspond to the general formula with
heterocyclic compounds such as an isoozazolone
compound, an oxazolone compound, a thionaphthene
compound, a pyrazolone compound, a barbizuric acid
compound, a hydantoin compound, and a rhodain compound,
20 for example, having an active methylene group which is
adjacent to a carbonyl group in a molecule. Y31, Y32,
Y41, Y42, and Y represent hetero atoms which are
identical to or different from each other, the atoms
being selected from elements of the sixteenth family in
25 the periodic table such as an oxygen atom, a sulfur
atom, a selenium atom, and a tellurium atom, for
example.
The organic metal complex represented by the
general formula is generally used in a mode in which
one or a plurality of metal complexes are oriented at a
metal (center atom). Examples of metal elements
5 serving as the center atoms, for example, can include
scandium, yttrium, titanium, zirconium, hafnium,
vanadium, niobium, tantalum, chromium, molybdenum,
tungsten, manganese, technetium, rhenium, iron,
lutenium, osmium, cobalt, rhodium, iridium, nickel,
10 palladium, platinum, copper, silver, gold, zinc,
cadmium, and mercury or the like. X^ in the general
formula represents a proper anodic ion including an
onium ion such as alkyl ammonium ion, a pyridinium ion,
and quinolinium ion, for example.
15 A test for reproduction degradation was carried
out by recording an ETM modulation signal in a writeonce
type R optical disk fabricated by using the above
5 types of organic dye materials, and then, obtaining
reproduction count when a degree of signal modulation
20 is 0.4 or less, PRSNR is 15 or less, and SbER is 5 x
10~5 or more in the case where a track recorded by
predetermined reproduction laser power was continuously
reproduced (still-reproduced) at a line speed of 6.61
m/sec. The reproduction light stability is better as
25 the reproduction count increases. A result is shown in
FIG. 122. It was found that the reproduction
durability count is 1,000,000 or more at the
reproduction laser power of 0.4 mW in an "L to H" type
optical disk using a mixture dye. Namely, it was found
that a mixture of a plurality of an organic metal
complex simplex and an organic metal complex cation and
5 anion has excellent reproduction light durability. In
particular, the fifth mixture dye of two types of
organic metal complex cation and anion and an organic
metal complex simplex achieved 1,500,000 or more in
reproduction light durability.
10 In addition, with respect to the reflectivity
obtained by measuring I11H after recording, the
reflectivity was 12% in the case of the first dye "A"
and 30% in the case of the second dye. The
reflectivity was 14% in the case of the third dye U + W
15 + Y; the reflectivity was 22% in the case of the fourth
dye B + W -I- Y; and the reflectivity was 28% in the case
of the fifth dye U + W + Y. Therefore, it was
experimentally found convenient that the reflectivity
ranges from 14% to 28% in order to obtain the
20 reproduction light durability of 1,000,000 times or
more.
In addition, a novel embodiment that the following
concept of constitution of a mixture dye is proper was
obtained. This constitution consists of at least two
25 portions, i.e., a "recording function dye" and a
"reproduction light durability function dye". An
organic metal complex such as A, B, or Y can be used as
the former "recording function dye". The organic metal
complex is not limited to these structures or
skeletons. In addition, U, V, W, WW, WWW, and WWWW can
be used. Use of an anion and cation type is convenient
5 to further improve reproduction light durability.
Mainly, it is preferable to use a dye of this portion
having excellent performance of recording and
reproducing characteristics. The latter "reproduction
light durability function dye" serves to improve the
10 reproduction light durability. Although the use of one
type of the dye will suffice, the use of two types is
further effective. An organic metal complex such as A,
B, or Y can also be used. The organic metal complex is
not limited to these structures and skeletons. In
15 addition, U, V, W, WW, WWW, and WWWW can be used. The
use of a cation and anion type is convenient to further
improve the reproduction light durability. In
particular, the use of dyes W, WW, WWW, and WWWW is
preferable to improve the reproduction light
20 durability. For example, in the case where two types
are used, it is convenient to carry out recording of a
burst cutting area (BCA) by adjusting a maximum
absorption wavelength of one dye in the range of 630 nm
to 680 nm, and large BCA amplitude can be obtained. In
25 the case where a high level voltage (IBH) of a BCA
signal is set to 100%, it becomes possible to set the
BCA signal amplitude to 20% or more. IBL/IBH can be
set to 0.80 or less when this amplitude is expressed by
using a low level voltage (IBL).
In addition, with respect to a mixture ratio of
the "recording function dye" and the "reproduction
light durability function dye", it is preferable that
the "reproduction light durability function dye" range
from 30% to 400% in the case where the "recording
function dye" is set to 100%. It is particularly
preferable that the above dye range from 150% to 300%.
The best ratio should be set to 200%. It is preferable
that a dye added for BCA recording range from 5% to
50%. It is particularly preferable that the dye range
from 10% to 30%. The best ratio should be set to 15%.
The present invention is not limited to the abovedescribed
embodiments. At a stage of carrying out the
invention, the present invention can be embodied by
modifying constituent elements without departing from
the spirit of the invention. In addition, a variety of
inventions can be formed by using a proper combination
of a plurality of constituent elements disclosed in the
above-described embodiments. For example, some
constituent elements may be eliminated from all the
constituent elements shown in the embodiments.
Further, the constituent elements over the different
embodiments may be properly combined with each other.
Examples
Now, examples of the recording film will be
described here. In the following examples, one-sided
single layer mediums and one-sided double layer mediums
were fabricated. As a substrate, there was used a
polycarbonate (PC) substrate having thickness of 0.6 mm
fabricated by injection molding. A groove was formed
on the substrate in track pitches of 0.4 (am. A onesided
single layer medium was fabricated as follows.
That is, a dye was coated on the substrate in
accordance with a spin coat technique. On the coated
substrate, a reflection layer was formed in a
sputtering technique. On the formed reflection layer,
a PC substrate having thickness of 0.6 mm was adhered
by using an UV curing resin.
On the other hand, two methods can be used in the
case of the one-sided double layer medium. In a first
method, the one-sided double layer medium was
fabricated as follows. On an LO substrate, a dye was
coated in accordance with a spin coat technique. On
the coated substrate, a semipermeable reflection layer
was formed in accordance with a sputtering technique.
On the formed layer, an interlayer separating layer and
a groove for LI were formed in accordance with a 2P
technique (photo polymer technique). Further, on the
formed groove, a dye was coated again in accordance
with the spin coat technique. On the coated layer, a
reflection layer was formed in accordance with the
sputtering technique. Lastly, a PC substrate having
thickness of 0.6 mm was adhered to the formed
reflection layer by using a UV curing resin. In this
method, the LO-layer semipermeable reflection film was
formed, and further, another layer can be formed on the
formed reflection film for adjustment of optical
characteristics. In a second method, the following
preparation was carried out. On an LO substrate, a dye
was coated in accordance with a spin coat technique.
On the coated substrate, a semipermeable reflection
layer was formed in accordance with a sputtering
technique. In addition, on the LI substrate, first, a
reflection layer is formed in accordance with a
sputtering technique. On the formed reflection layer,
a dye was coated in accordance with a spin coat
technique. The fabricated LO and LI substrates were
adhered to each other using a UV curing resin while
their respective semipermeable reflection film and
organic dye film were set inwardly. In this method,
another layer can be inserted between an organic dye
layer which is a recording layer of Ll and the UV
curing resin for the purpose of stabilizing an organic
dye which is a recording film material of Ll or
adjusting optical characteristics. In the present
embodiment, testing was carried out using mediums
fabricated by both of the methods.
For evaluation, a disk evaluation device ODU-1000
available from a PULSTEC Co., Ltd. was used. This
device includes a blue violet semiconductor laser
having a wavelength of 405 nm and an objective lens of
NA = 0.65. Recording and reproducing testing was
carried out under a condition for a linear velocity of
6.6 m/sec. Evaluation was carried out with respect to
five characteristics below. That is, measurements of
(a) SbER (Simulated bit Error Rate); (b) PRSNR (Partial
Response Signal to Noise Ratio) ; (c) Modulation; (d)
reflectivity of data portion; and (e) read stability of
each storage medium were carried out. The evaluation
criteria were defined as follows. That is, in the case
where continuous readout is carried out at an SbER of
5.0 x 10~5 or less, a PRSNR of 15.0 or more, a
modulation of 0.4 or more, a reflectivity of 14% or
more in the case of a one-sided single layer medium or
a reflectivity of 4% or more in each of the LO and LI
mediums in the case of one-sided double layer, at power
of 0.4 mW in the case of a one-sided single layer
medium and at any good power of 0.4 mW to 0.8 mW in the
case of a one-sided double layer medium for read
stability, even if readout was carried out for
1,000,000 times or more, characteristics (a) to (e)
must achieve their target values. Read power in the
one-sided double layer medium was selected as a
condition such that SN ratios and signal amplitudes of
reproduction signals are substantially equal to each
other in LO and LI. This is because optical
characteristics (LO reflectivity and transmittance, LI
reflectivity) and sensitivity of a medium and a signal
amplitude and SN ratio of reflection signal are
different depending on a dye of a medium and a material
and a film thickness or the like of the reflection
film. However, the read power values of LO and LI are
often identical to each other. In the case where all
the characteristics met the target values, the storage
medium was defined as "good", and if only one
characteristic failed to meet its target value, the
medium was defined as being "unacceptable".
There were used three types of organic dye
recording materials (occasionally simply referred to as
dye), i.e., (1) cation-anion based; (2) organic metal
complex (azo based); and (3) mixture dye of cationanion
based and organic metal complex (azo based). The
used reflection films are binary Ag allows, i.e., AgAu,
AgBi, AgCa, AgCe, AgCo, AgGa, AgLa, AgMg, AgN, AgNi,
AgNd, AgPd, AgY, AgW, AgZr; and tertiary Ag alloys,
i.e., AgAlMg, AgAuBi, AgBiGa, AgAuCo, AgAuCe, AgAuNi,
AgAuMg, AgBiMg, AgBiN, AgBiPd, and AgBiZr; and
advantageous effect in the case where additive elements
of group 1 and group 2 and N (nitrogen) were added at
the same time was verified. As a film forming method,
there was used each of Ag alloy targets described
previously or there was used a multi-dimensional
simultaneous sputtering in which a sputtering condition
was adjusted so as to obtain a desired constitution.
Reaction with nitrogen was carried out by using as a
sputtering gas a mixture gas of Ar and N (nitrogen)
instead of only Ar. The constitution, film thickness,
and substrate shape of dyes and reflection films were
adjusted, respectively, so that signal characteristics
are good.
Additive amounts of additive elements in an Ag
alloy reflection film used in each of examples were
four levels of 0.05 at%, 1 at%, 2 at%, and 5 at%, and
three levels of (1), (2), and (3) were used for organic
dye materials. Therefore, a total number of sample
types produced in examples were 12. FIG. 123 and
FIG. 124 each show additive element names of Ag-alloy
reflection films used in examples, and FIG. 125 shows
Ag-alloy reflection films and amounts of additive
elements used in comparative examples and a chart of
combination with organic dye materials. As organic dye
material (4), there was used a conventionally used dye
material, i.e., a phthalocyanine based organic dye and
super-green dye (IRAPHOR Utragreen MX available from
Ciba Speciality Chemicals).
Example 1
In example 1, a one-sided single layer storage
medium was produced, and testing was carried out. Au
was used as an additive element of an Ag-alloy
reflection film; four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used as additive amounts; and three types
(1), (2), and (3) were used as organic dye materials
for recording films. In order to cover all
combinations of amounts of additive elements and dye
materials, all combinations, 12 types of storage
mediums were produced, and evaluation of the recording
and reproducing characteristics were carried out.
FIG. 126 specifically exemplifies constitutions of
reflection films and combinations of organic dye
materials for recording films.
When the characteristics (a) to (e) of the
produced storage mediums were evaluated, the evaluation
results were obtained as shown in FIG. 127.
As is evident from these results, each of the
storage mediums achieved the target values; SbER of
5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation
of 0.4 or more; reflectivity of 14% or more; and read
stability of 1,000,000 times or more. Therefore, each
of the storage mediums obtained "good" characteristics.
Example 2
In example 2, one-sided single layer and double
layer storage mediums were produced. Bi was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
was used as organic dye materials for recording films.
As in example 1, 12 combinations of storage mediums
were produced, and evaluation of recording and
reproducing characteristics were carried out. With
respect to the one-sided double layer storage medium, a
medium whose Bi additive amounts are 0.05 at% and 1 at%
was produced, and with respect to the one-sided single
layer storage medium, a medium whose Bi additive
amounts are 1 at%, 2 at%, and 5 at% was produced,
respectively, and evaluation was carried out. FIG. 128
specifically exemplifies constitutions of reflection
films and combinations of organic dye materials for
recording films.
When the characteristics (a) to (e) of the
produced storage mediums were evaluated, the evaluation
results were obtained as shown in FIG. 129. In
FIG. 129, data represented with "double layer"
indicates data on a one-sided double layer medium in
the case where there exists data on both of a one-sided
single layer medium and a one-sided double layer
medium.
As is evident from these results, each of the
storage mediums achieved the target values; SbER of
5.0 x 10~5 or less; PRSNR of 15.0 or more; modulation
of 0.4 or more; reflectivity of 4% or more relevant to
the one-sided double layer medium in both of LO and LI
and 14% or more relevant to the one-sided single layer
medium; and read stability of 1,000,000 times or more.
Therefore, each of the storage mediums obtained "good"
characteristics.
Example 3
In example 3, as in example 1, a one-sided single
layer storage medium was produced. Ca was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 4
In example 4, as in example 1, a one-sided single
layer storage medium was produced. Ce was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 5
In example 5, as in example 1, a one-sided single
layer storage medium was produced. Co was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 6
In example 6, a one-sided single layer and a onesided
double layer storage mediums were produced. Ga
was used as an additive element of an Ag-alloy
reflection film; four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used as amounts of additives; and three
types (1), (2), and (3) were used as organic dye
materials for recording films. As in example 1, 12
types of storage mediums were produced, and evaluation
of recording and reproducing characteristics were
carried out. With respect to a medium whose Ga
additive amounts are 0.05 at% and 1 at%, a one-sided
double layer storage medium was produced, and with
respect to a medium whose Ga additive amounts were 2
at% and 5 at%, a one-sided single layer storage medium
was produced, respectively, and evaluation was carried
out. Each of the storage mediums achieved the target
values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or
more; modulation of 0.4 or more; reflectivity of 4% or
more relevant to the one-sided double layer medium in
both of LO and LI and 14% or more relevant to the onesided
single layer medium; and read stability of
1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 7
In example 7, as in example 1, a one-sided single
layer storage medium was produced. La was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10"^
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 8
In example 8, one-sided single layer and double
layer storage mediums were produced. Mg is used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. With respect to a
medium whose Mg additive amounts are 0.05 at% and
1 at%, a one-sided double layer storage medium was
produced, and with respect to a medium whose Mg
additive amounts were 2 at% and 5 at%, a one-sided
single layer storage medium was produced, respectively,
and evaluation was carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 4% or more relevant to the onesided
double layer medium in both of LO and LI and 14%
or more relevant to the one-sided single layer medium;
and read stability of 1,000,000 times or more.
Therefore, each of the storage mediums obtained "good"
characteristics.
Example 9
In example 9, as in example 1, a one-sided single
layer storage medium was produced. N was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 10
In example 10, as in example 1, a one-sided single
layer storage medium was produced. Ni was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 11
In example 11, as in example 1, a one-sided single
layer storage medium was produced. Nd was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 12
In example 12, as in example 1, a one-sided single
layer storage medium was produced. Pd was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recordingj and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; Sl^ER of 5.0 x 10~^
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; an of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 13
In example 13, as in example 1, ^ one-sided single
layer storage medium was produced. Y|was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 at% were used as
amounts of additives; and three types!(1), (2), and (3)
were used as organic dye materials fojf: recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recordingjand reproducing
characteristics were carried out. Eacph of the storage
mediums achieved the target values; Slj)ER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; ancjl read stability
of 1,000,000 times or more. Therefor4, each of the
storage mediums obtained "good" characteristics.
Example 14
In example 14, as in example 1, ^ one-sided single
layer storage medium was produced. W was used as an
additive element of an Ag-alloy reflection film; four
types 0.05 at%, 1 at%, 2 at%, and 5 atj% were used as
amounts of additives; and three types (1), (2), and (3)
were used as organic dye materials for recording films.
As in example 1, 12 types of storage mediums were
produced, and evaluation of recording and reproducing
characteristics were carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 14% or more; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 15
In example 15, a one-sided single layer and a onesided
double layer storage mediums were produced. Zr
is used as an additive element of an Ag-alloy
reflection film; four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used as amounts of additives; and three
types (1), (2), and (3) were used as organic dye
materials for recording films. As in example 1, 12
types of storage mediums were produced, and evaluation
of recording and reproducing characteristics were
carried out. With respect to a medium whose Zr
additive amounts are 0.05 at% and 1 at%, a one-sided
double layer storage medium was produced, and with
respect to a medium whose Zr additive amounts were
2 at% and 5 at%, a one-sided single layer storage
medium was produced, respectively, and evaluation was
carried out. Each of the storage mediums achieved the
target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 4% or more relevant to the one-sided double layer
medium in both of LO and LI and 14% or more relevant to
the one-sided single layer medium; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 16
In example 16, as in example 1, a one-sided single
layer storage medium was produced, Al and Mg were used
as additive elements of an Ag-alloy reflection film,
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
as total additive amounts of Al and Mg; and three types
(1), (2), and (3) were used as organic dye materials
for recording films. As in example 1, 12 types of
storage mediums were produced, and evaluation of
recording and reproducing characteristics were carried
out. Each of the storage mediums achieved the target
values; SbER of 5.0 x 10~5 or less; PRSNR of 15.0 or
more; modulation of 0.4 or more; reflectivity of 14% or
more; and read stability of 1,000,000 times or more.
Therefore, each of the storage mediums obtained "good"
characteristics.
Example 17
In example 17, a one-sided single layer and a onesided
double layer storage mediums were produced. Au
and Bi were used as additive elements of an Ag-alloy
reflection film, four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used as total additive amounts of Au and Bi;
and three types (1), (2), and (3) were used as organic
dye materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. With respect to a medium whose Ga
additive amounts are 0.05 at% and 1 at%, a one-sided
double layer storage medium was produced, and with
respect to a medium whose Ga additive amounts were
2 at% and 5 at%, a one-sided single layer storage
medium was produced, respectively, and evaluation was
carried out. Each of the storage mediums achieved the
target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 4% or more relevant to the one-sided double layer
medium in both of LO and LI and 14% or more relevant to
the one-sided single layer medium; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 18
In example 18, a one-sided single layer and a onesided
double layer storage mediums were produced. Bi
and Ga were used for additive elements of an Ag-alloy
reflection film; four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used for total additive amounts of Bi and
Ga; and three types (1), (2), and (3) were used for
organic dye materials for recording films. As in
example 1, 12 types of storage mediums were produced,
and evaluation of recording and reproducing
characteristics were carried out. With respect to a
medium whose Ga additive amounts are 0.05 at% and
1 at%, a one-sided double layer storage medium was
produced, and with respect to a medium whose Ga
additive amounts were 2 at% and 5 at%, a one-sided
single layer storage medium was produced, respectively,
and evaluation was carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 4% or more relevant to the onesided
double layer medium in both of LO and LI and 14%
or more relevant to the one-sided single layer medium;
and read stability of 1,000,000 times or more.
Therefore, each of the storage mediums obtained "good"
characteristics.
Example 19
In example 19, as in example 1, a one-sided single
layer storage medium was produced. Au and Ce were used
as additive elements of an Ag-alloy reflection film;
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
for total additive amounts of Au and Ce; and three
types (1), (2), and (3) were used for organic dye
materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. Each of the storage mediums achieved
the target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 14% or more; and read stability of 1,000,000 times
or more. Therefore, each of the storage mediums
obtained "good" characteristics.
Example 20
In example 20, as in example 1, a one-sided single
layer storage medium was produced. Au and Co were used
as additive elements of an Ag-alloy reflection film;
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
for total additive amounts of Au and Co; and three
types (1), (2), and (3) were used for organic dye
materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. Each of the storage mediums achieved
the target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 14% or more; and read stability of 1,000,000 times
or more. Therefore, each of the storage mediums
obtained "good" characteristics.
Example 21
In example 21, as in example 1, a one-sided single
layer storage medium was produced. Au and Ni were used
as additive elements of an Ag-alloy reflection film;
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
for total additive amounts of Au and Ni; and three
types (1), (2), and (3) were used for organic dye
materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. Each of the storage mediums achieved
the target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 14% or more; and read stability of 1,000,000 times
or more. Therefore, each of the storage mediums
obtained "good" characteristics.
Example 22
In example 22, as in example 1, a one-sided single
layer storage medium was produced. Au and Mg were used
as additive elements of an Ag-alloy reflection film;
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
for total additive amounts of Au and Mg; and
three types (1), (2), and (3) were used for organic dye
materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. Each of the storage mediums achieved
the target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 14% or more; and read stability of 1,000,000 times
or more. Therefore, each of the storage mediums
obtained "good" characteristics.
Example 23
In example 23, a one-sided single layer and a onesided
double layer storage mediums were produced. Bi
and Mg were used for additive elements of an Ag-alloy
reflection film; four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used for total additive amounts of Bi and
Mg; and three types (1), (2), and (3) were used for
organic dye materials for recording films. As in
example 1, 12 types of storage mediums were produced,
and evaluation of recording and reproducing
characteristics were carried out. With respect to a
medium whose Ga additive amounts are 0.05 at% and
1 at%, a one-sided double layer storage medium was
produced, and with respect to a medium whose Ga
additive amounts were 2 at% and 5 at%, a one-sided
single layer storage medium was produced, respectively,
and evaluation was carried out. Each of the storage
mediums achieved the target values; SbER of 5.0 x 10~5
or less; PRSNR of 15.0 or more; modulation of 0.4 or
more; reflectivity of 4% or more relevant to the onesided
double layer medium in both of LO and LI and 14%
or more relevant to the one-sided single layer medium;
and read stability of 1,000,000 times or more.
Therefore, each of the storage mediums obtained "good"
characteristics.
Example 24
In example 24, a one-sided single layer and a onesided
double layer storage mediums were produced. Bi
and N were used for additive elements of an Ag-alloy
reflection film; four types 0.05 at%, 1 at%, 2 at%, and
5 at% were used for total additive amounts of Bi and N;
and three types (1), (2), and (3) were used for organic
dye materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. With respect to a medium whose Ga
additive amounts are 0.05 at% and 1 at%, a one-sided
double layer storage medium was produced, and with
respect to a medium whose Ga additive amounts were
2 at% and 5 at%, a one-sided single layer storage
medium was produced, respectively, and evaluation was
carried out. Each of the storage mediums achieved the
target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 4% or more relevant to the one-sided double layer
medium in both of LO and LI and 14% or more relevant to
the one-sided single layer medium; and read stability
of 1,000,000 times or more. Therefore, each of the
storage mediums obtained "good" characteristics.
Example 25
In example 25, as in example 1, a one-sided single
layer storage medium was produced. Bi and Pd were used
as additive elements of an Ag-alloy reflection film;
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
for total additive amounts of Bi and Pd; and three
types (1), (2), and (3) were used for organic dye
materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. Each of the storage mediums achieved
the target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 14% or more; and read stability of 1,000,000 times
or more. Therefore, each of the storage mediums
obtained "good" characteristics.
Example 26
In example 26, as in example 1, a one-sided single
layer storage medium was produced. Bi and Zr were used
as additive elements of an Ag-alloy reflection film;
four types 0.05 at%, 1 at%, 2 at%, and 5 at% were used
for total additive amounts of Bi and Zr; and three
types (1), (2), and (3) were used for organic dye
materials for recording films. As in example 1,
12 types of storage mediums were produced, and
evaluation of recording and reproducing characteristics
were carried out. Each of the storage mediums achieved
the target values; SbER of 5.0 x 10~5 or less; PRSNR of
15.0 or more; modulation of 0.4 or more; reflectivity
of 14% or more; and read stability of 1,000,000 times
or more. Therefore, each of the storage mediums
obtained "good" characteristics.
Comparative Example 1
In comparative example 1, as in example 1, a onesided
single layer storage medium was produced. Al was
used as an additive element of an Ag-alloy reflection
film; two types of 0.04 at% and 6 at% were used as
additive amounts; and a phthalocyanine based organic
dye and super-green dye (IRGAPHOR Ultragreen MX
available from Ciba Speciality Chemicals) were used as
organic dye materials for recording films. Three types
of storage mediums were produced, and evaluation of
recording and reproducing characteristics were carried
out. In the case where the additive amount of Al
contained in the Ag alloy was defined as 6 at%, the
modulation and reflectivity did not meet 0.4 or more
and 14% or more which are their target values, and was
"unacceptable". In addition, in the case where the
additive amount of Al contained in the Ag alloy was
defined as 0.04 at%, in particular, read stability did
not achieve 1,000,000 times or more. Therefore, each
of the storage mediums achieved only "unacceptable"
characteristics.
Comparative example 2
In comparative example 2, as in example 1, a onesided
single layer storage medium was produced. Cu was
used as an additive element of an Ag-alloy reflection
film; two types of 0.04 at% and 6 at% were used as
additive amounts; and a phthalocyanine based organic
dye and super-green dye (IRGAPHOR Ultragreen MX
available from Ciba Speciality Chemicals) were used as
organic dye materials for recording films. A storage
medium was produced, and evaluation of recording and
reproducing characteristics were carried out. In the
case where the additive amount of Cu contained in the
Ag alloy was defined as 6 at%, the modulation and
reflectivity did not meet 0.4 or more and 14% or more
which are their target values, and was "unacceptable".
In addition, in the case where the additive amount of
Cu contained in the Ag alloy was defined as 0.04 at%,
in particular, read stability did not achieve
1,000,000 times or more. Therefore, each of the
storage mediums achieved only "unacceptable"
characteristics.
Comparative example 3
In comparative example 3, as in example 1, a onesided
single layer storage medium was produced. Pd was
used as an additive element of an Ag-alloy reflection
film; two types of 0.04 at% and 6 at% were used as
additive amounts; and a phthalocyanine based organic
dye and super-green dye (IRGAPHOR Ultragreen MX
available from Ciba Speciality Chemicals) were used as
organic dye materials for recording films. A storage
medium was produced, and evaluation of recording and
reproducing characteristics were carried out. In the
case where the additive amount of Pd contained in the
Ag alloy was defined as 6 at%, the modulation and
reflectivity did not meet 0.4 or more and 14% or more
which are their target values, and was "unacceptable".
In addition, in the case where the additive amount of
Pd contained in the Ag alloy was defined as 0.04 at%,
in particular, read stability did not achieve
1,000,000 times or more. Therefore, each of the
storage mediums achieved only "unacceptable"
characteristics.
According to an embodiment, a storage medium
comprises a transparent resin substrate on which a
groove is formed; a recording layer formed on the
groove on the transparent resin substrate, the
recording layer using an organic dye material and
recording information with a light beam of 620 nm or
less in wavelength; a reflection layer formed on the
recording layer; and a prevention layer formed between
the recording layer and the reflection layer, the
prevention layer preventing degradation of
characteristics of the reflection layer.
In the storage medium, the reflection layer may
comprise Ag and an additive element selected from Al,
Au, Bi, Ca, Ce, Co, Cu, Ga, La, Mg, N, Ni, Nd, Pd, Pt,
Rh, Y, W, and Zr.
In the storage medium, a total amount of the
additive elements may range from 0.05 at% to 5 at%.
While certain embodiments of the inventions have
been described, these embodiments have been presented
by way of example only, and are not intended to limit
the scope of the inventions. Indeed, the novel methods
and systems described herein may be embodied in a
variety of other forms; furthermore, various omissions,
substitutions and changes in the form of the methods
and systems described herein may be made without
departing from the spirit of the inventions. The
accompanying claims and their equivalents are intended
to cover such forms or modifications as would fall
within the scope and spirit of the inventions.

We claim:
1. A storage medium comprising:
a transparent layer (2-2) which passes light;
a recording layer (3-2) formed of an organic dye material, the light passed through the transparent layer being incident to the recording layer;
a reflection layer (4-2) formed of Ag alloy and reflecting the light passed through the recording layer; and
a prevention layer (8) formed at an interface between the reflection layer (4-2) and the recording layer (3-2) and preventing degradation of characteristic of the reflection layer (4-2), wherein
the recording layer comprises an unrecorded portion,
a maximum absorption wavelength (λmax write) at which a light absorbance in the unrecorded portion is maximum is longer than 405nm,
a light absorbance in the unrecorded portion at a wavelength of 355 nm is not smaller than 40% of the light absorbance at the maximum absorption wavelength,
information is recordable by light having a wavelength of 405nm,
an intensity of light reflected by the reflection layer and passed through a recording portion of the recording layer is higher than an intensity of light reflected by the reflection layer and passed through the unrecorded portion, and
the reflection layer comprises silver Ag and an additive element which prevents degradation of recording and reproducing characteristics due to reaction with silver Ag and the organic dye material, the additive element being selected from aluminium A1; gold Au; bismuth Bi; calcium Ca; cerium Ce, cobalt Co, gallium Ga, lanthanum La; magnesium Mg; nitrogen N; nickel Ni; neodium Nd; palladium Pd; yttrium Y; tungsten W and zirconium Zr.
2. The storage medium as claimed in claim 1, wherein
the additive element ranges from 0.05 at% to 5 at% in a total atom number of additive element relative to Ag content.

3. The storage medium as claimed in claim 1, wherein
the prevention layer prevents a recording and reproduction characteristic change due to reaction between the reflection layer (4-2) and the recording layer.
4. A method for reproducing information recorded in a storage medium as claimed
in one of claims 1 to 3, the method comprising:
irradiating the storage medium with a light beam of 405 nm in wavelength; and
reproducing information recorded in the storage medium based on a reflection light beam of the irradiated light beam.
5. A method for recording information in a storage medium as claimed in one of
claims 1 to 3, the method comprising:
irradiating the storage medium with a light beam of 405 nm in wavelength based on information to be recorded in the storage medium; and
recording information in the storage medium based on the irradiated light beam.

Documents:

934-del-2006-abstract.pdf

934-del-2006-assignments.pdf

934-DEL-2006-Claims-(15-11-2010).pdf

934-DEL-2006-Claims-(21-11-2011).pdf

934-DEL-2006-Claims-(22-11-2011).pdf

934-del-2006-Claims-(31-03-2006).pdf

934-del-2006-claims.pdf

934-DEL-2006-Correspondence Others-(21-11-2011).pdf

934-DEL-2006-Correspondence Others-(22-11-2011).pdf

934-DEL-2006-Correspondence-Others-(15-11-2010).pdf

934-DEL-2006-Correspondence-Others.pdf

934-DEL-2006-Description (Complete)-(15-11-2010).pdf

934-del-2006-description (complete).pdf

934-DEL-2006-Drawings-(15-11-2010).pdf

934-del-2006-drawings.pdf

934-del-2006-form-1.pdf

934-del-2006-form-18.pdf

934-DEL-2006-Form-2-(15-11-2010).pdf

934-del-2006-form-2.pdf

934-del-2006-form-3.pdf

934-del-2006-form-5.pdf

934-del-2006-gpa.pdf

934-DEL-2010-Correspondence-Others-(17-05-2010).pdf

934-DEL-2010-Form-3-(17-05-2010).pdf

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Patent Number

249954

Indian Patent Application Number

934/DEL/2006

PG Journal Number

47/2011

Publication Date

25-Nov-2011

Grant Date

24-Nov-2011

Date of Filing

31-Mar-2006

Name of Patentee

KABUSHIKI KAISHA TOSHIBA

Applicant Address

1-1 SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.

Inventors:

#	Inventor's Name	Inventor's Address
1	NAKAI TSUKASA	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.
2	MORITA SEIJI	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.
3	TAKAZAWA KOJI	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.
4	OOTERA YASUAKI	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.
5	MORISHITA NAOKI	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.
6	UMEZAWA KAZUYO	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.
7	ANDO HIDEO	C/O INTELLECTUAL PROPERTY DIVISION, TOSHIBA CORPORATION,1-1, SHIBAURA 1-CHOME, MINATO-KU, TOKYO 105-8001, JAPAN.

PCT International Classification Number

N/A

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2005-104725	2005-03-31	Japan