Title of Invention

"METHOD AND ASSOCIATED APPARATUS FOR THE STANDARDIZED GRADING OF GEMSTONES"

Abstract A method and associated apparatus (5) for the standardized grading of gemstones is provided. The system gauges the spectral response of a gemstone subject to a plurality of incident light sources (77, 64, 90, 92, 102) within an imaging apparatus. The operation of the imaging apparatus is controlled by an instruction set of a local station control data processor (12). Light energy data is captured in the form of pixel data sets via a charge coupled device of the imaging apparatus of the local station (8). The control data processor data of the local station is operably linked to analysis station (14). Gemstones qualities are analyzed by the plurality of light sources (92, 90, 102) of the imaging apparatus (5) and quantified relative to model pixel data sets of the database and recorded for future reference therein.
Full Text METHOD AND ASSOCIATED APPARATUS FOR THE STANDARDIZED GRADING OF GEMSTONES
FIELD OF THE INVENTION
This invention relates rogemstone grading systems. More specifically, the present invention provides an automated gemstonc pradinf, and data management system for use in appraising the value of a gemstonc. and to uniquely identify it.
BACKGROUND OF THE INVENTION
The monetary value of diamonds, pearls, and other precious gemstones can vary considerably relative to the aesthetic features of each si one Such features as, color, clarity, cut, shape, brilliance, etc., are important subjective determinants of value. For example, it is not uncommon 1,1 find gemstones of identical size and weight varying significantly due to the effect of such subjective determinants. As such, consistent measurement of these characteristics is a first step towards a reliable estimate of a veinstone's monetary value.
Presently, a variety of instruments are utilized to grade gr.mstmu-s, such instruments include the simple eyeglass or loupe, ns well as many sophisticated imaging instruments. Imaging instruments are commonly utilized in evaluating the objective and subjective qualities of gemstones, these instruments include simple ultra-violet lamps, microscopes, chelsca filters, calcite type dichroscopes, refractometers, polariscopes, spectroscopes, etc. imaging instruments enable operators to visually analyze gemstones through illumination and magnification, or electronically gauge the gemslones refraction and/or reflection characteristics to incident light.
However, imaging instruments and systems are presently incapable, of producing a reliable and reproducible index of a gemstone' s objective and subjective qualities. The choice of imaging instrument, human judgment, and
visual perception are all factors which impact the consistency of gemstone appraisals. Additionally, such appraisals have been heretofore incapable oi measuring several subjective determinants such as brilliance, scintillation, polish, and cut quality.
For example, traditionally, the grading of a gemsrone's color fails to consider the size of the gemstone, its transparency, flaws, degce of fluorescence, a lack of standard practice in preparation of a sample, and whether or not equivalent levels of illumination were, utilized. A variety of instruments and methods for color grading rely on color comparison kits for visually comparing a sample, the kits are used to subjectively assign a coloi based on this comparison. Since it is well known that human judgment and eyesight vary from person to person, such color grading systems are, unreliable. Some sophisticated instruments assign color by measuring light frequencies transmitted through or reflected from a surface, while others use reference light to evaluate shifts in color spectra and yet others ronvrrt the light frequencies into tri-stimulus which are used to assign a coloi to an object. Yet, fluorescence present in more than 50% of the diamonds and mega other gemstoncs will shift color frequencies. Magnitude of UV radine on in a light source will therefore affect color grade. As can be apprecitone these devices have yet to achieve a level of consistency acceptable to the gem trade.
Moreover, these devices do not offer a system of assigning a cut grade to an object that matches any one of the several well known round and fancy gemstonc cuts. Cut analysis can be improved by direct measurements of The side, top, and bottom views of objects being analyzed. Based on these measurements, Proportions of objects can be measured and they can be assigned a shape, a cut grade, and sorted. The foregoing drvices are incapable of precisely obtaining with certainty the minimum and maximum dimensions of a gemstone, such as girdle or table measurements,
Similarly, the clarity of a diamond and other transparent gemstomes is
based on the number, size, and distribution of Haws, iiir.lusionr., bubbles, crystals, and any other foreign matter that will distract from its uiicinal flawless bdauty. Surface defects in the form of scratches, brutmg marks, naturals, and feather are also important to the quality of a gemstom. A process for automatically identifying location, size and type of internal flaws in gem stones has yet to be. developed.
Additionally, such subjective determinants as brilliancy and scintillation in certain gem stones is highly prized. Naturally, inconsistent limiting conditions will produce different brilliancy readings. While a lighting standard must be developed to obtain consistent results, it should be flexible enough to allow for differences in gemstones, presently, inconsistent brilliancy and scintillation valuation of gemstones is commonplace.
Such inconsistencies in evaluating the above objective and subjfiive. gemstone properties has encouraged the proliferation of sophisticated counterfeiting and synthetic gemstone industries which further obfuscate the gemstone appraisal process, identification or authentication of these objects is a primary component of a reliable gem appraisal practice. As sophisticated counterfeiting procedures are developed to alter appearance sudi as laser drilling, radiation, and the substitution of with highly reflective plastic- and liquids, evei more reliable equipment and procedures are nccessaiy to separate natural goods from those which have been altered, enhanced or those that arc man made. Furthermore, there is well established need in the jewelry trade to fingerprint a gemstone for future identification. Gemstones removed for cleaning or sold on consignment may be switched. Insurers and consumers arc interested in reclaiming losi or stolen goods reeoveicd by police or retailers. A method is needed that will accurately measure and automatically record many attributes of a gemstones which can be. used hierarchically to match a gemstone
In addition to the aforementioned security concerns, prr.M.nfly, gemstones must be shipped or sent by a courier foi iippiai-.il m toi
evaluation by an interested buyer. This activity is tnnc consuming, expensive.
and places inventory at risk. An electronic mean, of transferor text.
aumencal and visual data that aca.ra.ely represents the various atlribates of
a gemstone can significantly improve transactions while reductn,. associared slipping, insurance and security costs. This functionality requires no, only communication capability but a database capabilny that can automate recording of text, audio and video information from gem analyse The database must Insecure and fully integrate inventory functions with analysis, management, retailing, and marketing of gem stones and .nformatin,,
The apparatus in accordance with the present invcntion, provides a reliable and reproducible evaluation, measurement, and recording system for quantifying heretofore objective and subjective gemston. characteristies,.
SUMMARY OF THE INVENTION
A method and associated apparatus for the standardized grading of
gemstones is provided in which the spectral response of a gemstone Subjecl
to a plurality of incident liglu sources is captured via a charge coupled d-vice
(CCD). An imaging apparatus employing a CCD camera is operably linked
with an analysis station, the analysis station including a dau, processor and
database for proofing the spectral response data as captured by the CCD
camera in the form of pixel data sets. The database employs a library of
exemplary gemstone pixel data sets as measured by the apparatus, the library
data functioning to relate, compare, and distinguish the spectral response of
an individual gemstone's pixel data set to the reference pixel data sets ol the
database. The data processor of the analysis station provides an instruction

set for facilitating communication with the imaging apparatus, analyzing

communicated pixel sets, and producing repom to. identify the gemstonoe's shape, quantify, and reliably grade heretofore subjcctive, qualities, of gemstones The reports arc communicated from the analysis station to the imaging apparatus for reproduction by an operably linked ,local, printer
The data processor of the analysis station communicates with a control data processor of the imaging apparatus. The control data processor of the apparatus provides an instruction sei for automating the steps necessary to precisely position and operate the imaging hardware. The control data processor has local and wide area communication capability for communicating captured pixel data sets to the analysis station in addition to the hardware positioning/actuation analysis instruction scl
An object of the invention is to extract consistently and accurately, size, shape, and proportion information from the side, top, and bottom images of a ge Historic using the data processing instruction set This information is used for cut analysis, weight calculation, and for assigning a cut grade using a statistical procedure such as a cluster or linear discriminant analysis. Cut grade analysis is based on cut grade standards for different types of cuts and the respective proportions of various dimensions ot a gemstone, diamonds in particular.
Still another object of the invention is to measure color and assign a color grade to a gemstone. This is accomplished by usiup; an illuminant standard such as D55 recommended by the C.I.E. (International Commission on lllumination) having a color rendition and an ultra violet component that closely resembles North-Daylight. A database of these readings is developed for stones of different but known colors along with the size, cut, fluorescence and flaw information for each stone. This multivariatc data is used to assign a color grade using a statistical procedure such as fluster or linear discriminant analysis,
Yet another object of the invention is to identify, delineate, and measure flaws and assign a clarity grade to a gemstone. This is accomplished by immersing a gemstone in jefractive index liquid, illuminating the stone from the bottom/sides, and imaging it from the top. Additional illumination trom the top, front, and side is obtained and a stone is rotated to obtain the best image of internal flaws, inclusions etc. The captured image is, analysed
by a data processor to delineate and measure any features The size .and the location of the features relative to the size of the gemstonr and its cut is used to assign a clarity grade.
Still another object of the invention is to check lor fluorescence, its. intensity as well as the characteristics of the. radiation emitted as a result of ultra violet stimulation; This is accomplished by taking two images. A stone that fluoresces will yield a firsl R.G.B. reading (red, gree.n, blue) when illuminated by ultra violet radiation and a second R.C.H. reading with the ultra violet source disabled The variations in the two leadings are used to measure the degree of fluorescence, the color of visible emission spect, and a fluorescence grade is assigned based on this information. This imaging process eliminates the need for an expensive color camera sensitive to low level radiation or integrating an image over time.
A further object of the invention is to measure brilliance and scintillation of a gemstone. Images are taken from the table side of a gemsfone. After adjusting for the intensity of illuminat, an average of total illumination over the face of a gemstone is used to measure, brilliancy. Images used for brilliancy measurement are also used to measure .scintillation. This is accomplished by thresholding a gray scale image and measuring pixels above a certain minimum level to be determined by trade for different gemstones. The ratio of total pixels exceeding the defined ilueshold and the area of the face of a stone in pixels is used to calculate the scintillation of the gemstone.
Another objective of the invention is to measure reflectance from the table of the gemstone, identify surface scratches and describe the shape and size of the. table. For clear stones, a collimated light illuminates the table of a stone at an angle; image of the surface reflectance is captured and processed. A ratio of the average reflected light to the average value of the illnminant measures reflectance Thresholding is used to identify surface scratches which can be automatically measured by the number of pixels. A
morphological image algorithm is used to determine the shape and size of the table.
A further objective of the invention is to authemir.ate a gemsrone Each stone is identified by the quantified properties as determined by the imaging apparatus, and thosr values arc utilized to identify it The system is designed to evaluate multiple: properties of a gemstone ior authentication. Calculated weight from the apparatus can be compared to scale weight and refractive index of a stone can be calculated. Internal features of a stonr can be mapped, described and used in authentication, presr.ncce or absence. of fluorescence, its intensity and frequency can be calculated, and suiface features and textures as described above can be extracted from an image. Filters such as: Chelsea, Waltonhodgkinson-Hanneman, frequency, and polarization filters arc placed in the path of light between an object being analyzed and a lens to separate simulants and synthetics from natural stones.
Yet another object of the invention is to provide a database for storing text, video, graphic, and audio data corresponding to a pluraliiy of gemsiones. Furthennore, the database is capable of automated search, report generation, automatic input and oulpul of data from other machines and from the analytical component of the invention. The database is remoicly located frorn the apparatus to ensure the security of its contents.
Another object of the invention is to have secure local and wide aica communication capability to transfer text, video, graphic and audio data This capability is used for centralized data processing and to monitoi the performance of remotely distributed devices..
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary, as well as the following derailed description of the preferred embodiments of the present invention, will be belter understood when read in conjunction with the accompanying drawings in which:
Figure I shows a functional block diagram o1 the gemstone grading system in accordance with the present invention;
Figure 2 shows a front view of the imaging apparatus of the gcmstone grading system shown in Figure 1;
Figure 3 shows a front sectional view of the interior of the imaging apparatus of the gemstone grading system shown in Figure 1;
Figure 4 shows a top view of the imaging apparatus of the gcmstone grading system shown in Figure 1;
Figure 5 shows a top view of the bottom light assembly of the imaging apparatus of the gcmstone grading system shown in Figure 1;
Figure 6 is a schematic diagram of the electrical control circuit of the imaging apparatus shown in Figure 1;
Figure 7 is a side view of the imaging opparatu.s m a first imaging position;
Figure 8 is a side view of the imaging apparatus in a second imaging position.
Figure 9 is a side view of the imaging apparatus in a third imaging position;
Figure 10 is a logical flow diagram of the cut analysis method of operating the imaging apparatus of Figure 1;
Figure 10A is a continuation of the logical flow diagram of Figure 10 showing the color analysis method of operating the imaging apparatus of Figure 1; and
Figure 10B, is a continuation of the logical flow diagram ot Figure 10 the brilliance, scintillation, flaw and polish analysis method of operating tin-imaging apparatus of Figure 1.
DETAILED DESCRIPTION OF THE PREFERRED F.MBODIMF.NT
An automated gemstone grading and data managemenr system is
provided wherein the aesthetic and/or monetary value of a gcmsione is determined relative to the measured spectral response of light cncigy incident to a gemstonc. Gemslone-, are illuminated by a plurality of light sources such that the spectral response, of the gemstone is captured as a pixel data set, gauged, quantified and recorded tor future reference via a CCD eamera of an imaging apparatus.
Mnre particularly, the present invention provides a local unking station for the automated valuation of geinstoues. The local imaging station is uperably linked to an analysis station for communicating captmed incident light data sets thereto. The analysis station employs a data processor and model database for assessing the aesthetic and/or monetary value of ge.mslones by way of the communicated pixel data sets. Gcmstonc.s are subject to a plurality of incident light sources of the imaging apparatus The spectral response of a geinstonr in the incident light sources is quantified relative to model pixel data sets of the database and recorded for future reference therein.
The method and associated apparatus for the standardized grading of gemstoncs, gauges the spectral response of a gemstone subject to a plurality of incident light sources of tin; imaging apparatus. Incident light energy is captured via the charge coupled device of the imaging apparatus of the local station. The operation of the imaging apparatus is controlled by a local station control data processoi and instruction set. The control data pror.nr.sor of the local st.ition is operably linked to an analysis station, the station includes an analysis data processor and mass storage memory device. The memory device provides storage space for the instruction set of the analysis data processor as well as database records.
The data processor of the analysis station provides an insti notion set for facilitating communication with the imaging appaiatus, analyzing communicated pixel sets, and producing reports of the analysis function. The instruction set includes analytical and statistical image models which extract
pertinent objective aesthetic and vnluc attribute indicia from The pixel data sets. The reference value database serves as a model of exemplary gemstonc pixel data sets as detected by the imaging apparatus. The database provides a reference for comparing incident light data communicated to the analysis station, the model data functioning to relate, compare, and distinguish the spectral response of a gcmstone having unknuwn qualify subjected to the illumination protocol of thft imaging apparatus. Additionally, the analysis station includes a mass storage, memory devices for storing the reference value database, analysis instruction set, and report infonnation which may include text as well as visual and audio data. The reports art- communicated from the remotely located analysis station to the imaging apparatus by way of a telecommunication network such as a LAN (Local Area Network) or WAN (Wide Area Network) for reproduction at the local station via an attached printer.
The local station includes the imaging apparatus, control proccs:.uj,
and printer. The control dntn processor of the local station provides an
instruction set for automating the steps necessary for the prwcision positioning
and actuation of the components necessary to operate the imaging appaiatus.
The data processor has local and wide area communication capability for
communicating with the data processor of the analy-sis station vis a
communication port. A preferred embodiment of the system and
methods in accordance with the present invention wj|| now be described with reference to ihe enumerated drawing figures.
Referring now to Figure 1, the system includes a lor.al station 8 which is operably linked by way of a telecommunication network 13 to an analysis station 14. The local station 8 includes an electronic imaging apparatus, generally designated 5. for imaging a gemsione such as a diamond or pearl. Local station 8 also includes a control data processor 10 for controlling the operation of the imaging apparatus 5 by way of a programmed instruction set, and a printer 19. The data processor function is preferably performed by a
general purpose computer, such as a personal computer, including a microprocessor for the processing of the imaging apparatus instruction set. The control data processor 10 of local staiion 3 is programmed with one or more suitable network protocols to permit it to capture, and communicate, pixel data sets to the analysts station 14 with which it is operably linked.
In the preferred embodiment, the general purpose roinputm inrlntles volatile RAM (Random Access Memory) and non-voiatile ROM (Read Only Memory) for facilitating the use of known computer operaiing environments such as the Windows operating interface. The general purpose computer may additionally employ a data management software program to catalog, format and update commnunicated reports communicated from the analysis station 14. The interface software enables the visual display of data set reports and appraisals communicated from the analysis station 14. as well as the manual entry of information to the reports via the data management soltware A printer 19 is provided at the local station S for generating reports communicated from analysis station 14.
Imaging apparatus 5 of local station 8 includes .1 (CCD) charge coupled device 12 for capturing and communicating pixel data .sets to the data processor JO. The pixel data sets captured by the processing of gemstone 7 within apparatus 5 provide incident light data to the analysis station 14. The control data processor 10 of local station S communicates ihe captured pixel data sets to the remotely located analysis station 14.
The analysis station M includes a data processor 21, nonvolatile memory device 25, and printer 27. Analysis staiion 14 is ojx-rably linked byway of a telecommunication network 15 to local station 8. The data processor 21 of analysis station 14 operates the analysis and database instruction set for storing, comparing, and analyzing captured data sets. The database of analysis station 14 can be remotely queried or updated utilizing the software of the local station data processor 10. A printer 27 is provided at analysis station 14 for generating activity reports, appraisal repoii/., and the
like.
The data processor function of the. analysis station 14 is preferably
performed by a general purpose computer, such as a personal computcr or
main frame computer, including a microprocessor for the processing of the
analysis and database instruction set. The analysis station computer is
programmed with one or more suitable network protocols to permit it to
obtain pixel data sets from the local station 8 with which it is connected. In
the preferred embodiment, the general purpose compute; of analysis station
14 includes volatile RAM (Random Access Memory) and non-volatile ROM
(Read Only Memory) for facilitating the use of known computer operating
environments such as the Windows operating interface, in addition to mass
storage device 25 provided for the storage of generated analysis reports. The
processed image data sets enable reliable appraisal of the gemstones in
addition to verifying the authenticity and quality of eadi gemstonr. The-
analysis station may similarly employ data management software and encode
network communications with the appropriate application and network layer
protocols to facilitate known electronic commerce standards. T h e
memory device 25 of analysis station 14 may include volatile as well as non volatile forms of computer memory. Preferably, the database is stored in a non-volatile mass storage device such as a hard disk drive. Copies, of d;u;i set reports and npprnisnls may be transported via portable, memory mediums such as floppy disks, CD roms, DATs, etc. or communicated to A local station 8 or other remote backup sites over the telecommunication network In an alternative embodiment, the data processor function 10 of the local station S may be integrated with the imaging appaiatus 5 such that a stand alone imaging and control apparatus is provided. The stand alon«- unit functions to combine the general purpose personal computei with thai of the imaging apparatus 5 such that an on board dedicated data processor would be provided for communicating with remotely located analysis station 14 and controlling the operation of upparalus 5.
IMAGING APPARATUS
Referring now to Figure 2. imaging appa rains s is shown. The imaging apparatus 5 includes housing 2, dispJay 9, status lights 27, access door 29, filter arrays 23, 24, and 26, power switch 31, legs 35a-d, power indicator 33 and output port 16. The entire apparatus 5 is enclosed by the. housing 2; the housing 2 can be easily removed for access to the inside of the apparatus 5. Either plastic or metal may br. used for the. construction ot the housing. The housing seals the interior of the apparatus 5 from external light sources The interior surfaces of the housing are coated with a non-reflective light absorbing material in limit leflection of the plurality of lighting elements housed therein. Four leveling legs 35a-d with shock absoibing paels, are used to level the device and reduce vibrations. The. imaging apparatus 5 employs fan bl and 83 ro blow air into the imaging apparatus through air filter?; to facilitate air circulation such that dust docs not enter and settlf into the apparatus 5, the air circulation also ensures thai the ambient temperature does not exceed operating parameters.
Display 9 is preferably an LCD (Liquid Crystal Display) which provides a visual representation of the placement of a gemstone. 7 within imaging apparatus 5 such thai the gemstone may be optimally located uii a device platform. In a preferred embodiment, the LCD 9 displays instructions from the computer and the images of a stone beinf, analyzed. Howr.ver, in an alternative embodiment a monitor of an operably linked personal computer can perform this function. The statur, lights 7.7 an an array of LED's (Light Emitting Diodes) each one of which correspond to an operation of the imaging apparatus. The illumination of (he appropriate LED indicating the actuation of the corresponding apparatus function .such that monitoring troubleshooting is facilitated without removing the housing 2 of the. imaging apparatus 5.
The imaging apparatus 5 is supplied by 120VAC 60HZ power supply controlled by a toggle switch 31. The power switch 31 coanects the apparatus
5 with a power source, and LED indicator light 33 is. enabled upon powering the apparatus 5 by way of switch 31.
Access door 29 slidably engages the housing 2, providing access to the inlerior of imaging apparatus 5 for the placement of a gemsione therein Filter arrays 23. 24 and 26 slidably engage the imaging apparatus at locations designed to position the filter elements to block light encigy of a prer.rlected frequency from being captured by the internal CCD device of the imaging apparatus.
Output port 16 includes an AC power supply connector 37, an RS 232 INSTRUMENT port 39, DR 25 COMP control port 41, video purl -15, and SCSI port 43.
The AC power supply connector is attached to a powci source foi powering the electrical components of the apparatus 5. The COMP port controls the actuation to different electrical devices as dictated by the instruction set of the data processor 10 of the local .station 8. The INSTRUMENT port provides an auxiliary connection for use with additional gemstone grading instrumentation. Video port 45 transmits, pixel data sets from CCD camera 12 of the apparatus 5 to the data processor 10 of local station 8. SCSI port 43 is provided for the connection of computer peripherals such as a local hard disk or zip drive to the apparatus 5,
Referring now to Figure 3, a side sectional view of the: imaging apparatus 5 is shown. The imaging apparatus 5 of the local station provides pixel data sets for transmission to analysis station 14. The data sets are communicated in a graphic file format such as TIFF or JPG. The pixel chtta sets are incident light images captured by a charge coupled device. 12 of imaging apparatus 5, such as manufactured by JVC model #TK107OU and an appropriate lens attached thereto. The pixel data sets of light energy incident to the gemstone 7 arc processed by analysis station 14 to analyze these images and extract pertinent information therefrom to product; an appraisal report on the gemstone 7

Forward of the lens of CCD 12 is a filter assembly 26 capable of holding multiple filters used to block light of a desired spsrirum For example, infrared and ulira violet fillers are used to block in frated and ultra viokt light frequencies. Such filters are critical to coloi and fluoicsccnt analysis as infra red and ultra violel light are invisible to UK- human eye but affect readings taken by the CCD camera 12
For example, a diffraction grating may be used to obtain a sprctrnm oi light transmitted through or reflected from a geinstonc 7 for use in the identification of simulants; Similarly, a chclsca filter may be utilized to identify emeralds.
The. filter assembly 26 has a ring light 77 to illuminate a stone from a first direction. Light source 77 is used to detect surface1, scratches, facet sti uclures, and to perform color analysis of dark stones. An ultra violet light 64, capable of short, long wave, or black UV illumination is piuvidcd foi fluorescent analysis useful in identifying a gemstone 7, delecting treatments, measuring fluorescence, and distinguishing simulants from natural gemstoncs.
IMAGING PLATFORM
Referring more particularly to Figures 3-4, the CCD camera 12 is positioned to travel between a first location A and a second location B. The points A and B correspond lo a first and second positions ol a linear positioner 49 which travels along n focal axis 80 (i.e., the x-axis). The linear positioner 49 is driven by seivo motor 86 of the control circuitry 110 (shown in Fig. 6). The linear positioner is actuated to move the camera 12 between point A or B as dictated by the data processor 10 of local station 8, The instruction set of the data processor dictates the actuation of the linear positioner 49 to compensate for the vertical movement of the gemstone 7 away from the focal axis. The distance between positions A and B is preselected to correspond to the vertical travel distance of the gemstonc when positioned above or below the focal axis 80. Thus, the camera is refocused
on the gemslone image by varying its horizontal location, however it should be recognized that a camera having an automated lens assembly operably linked to the data processor 10 of local station 8 is within the scope of tin-invention. The linear positioner 49 obviates the need tor cost prohibitive auto focus systems.
GEMSTONE STACK
A unitary si age 59 travels along a processing axis 105 through three positions, namely UP, LEVEL, and DOWN. The unitary stage is partially shielded by a stage baffle 8.5". The stage baffle 85 is a partial rectangulat enclosure spanning the vertical length halfway between the LEVEL and DOWN and UP positions of the processing axis 105. The. baffle 85 obstructs light reflectance while passing light along a particular angle of incidence. The baffle enclosure has openings at the ends perpendicular to the processing axis to permit light enlry to the enclosure from the top and bottom light soujees. Similarly, the enclosure has its camera facing surfaces removed to permit light data to pass to the camera 12 at any of the three stage locations In the LEVEL position, the enclosure surface facing access door 29 is open to permit insertion of a gemstonc 7, as well as the surface facing light source 102.
The. unitary stage- 59 includes light directing means' 55 and 57,
motorized Y-axis linear positioner 87 actuated by servo motor S3 of circuitry
110, rotatable platform 53, translucent platform portion 51, and stage light 73.
The positions of the unitary stage 59, are defined by the alignment of the
platform 53 along y-axis positions UP, LEVEL, and DOWN, with the focal
axis 80; The LEVEL position defined as being aligned with the focal axis SO.
Light directing means' 55 and 57 are provided to direct images of gemstone
7 to camera 12 when the platform 53 is positioned above or below the local
axis SO. The light directing means' 55 and 57 may be specially oriented beam
splitters, lenses and/or reflective mirrors. In the preferred embodiment, the
light directing means' 53 and 57 are a combination beam splitter and mirror. The light directing means' include a minor and beam splitting portion on its facing surface such that either method can be selected for directing images to camera 7.
A stone to be analyzed is placed within the stage 59 with its table. side facing plaiform 53. The vertical movement of the stage along the, professing axis 105, between the UP, LHVEL, and DOWN positions, is enabled by the motorized Y-axis linear positioner 87 The preferred embodiment of the stage makes il feasible to obtain images of the front, bar.k, lop, and bottom of the gemstone 7 from a plurality of light sources and locations. The stage has a rotatable platform 53 rotated by a servo motor 120 of circuitry 110. The platform 53 rotates at predetermined intervals to facilitate imaging of the entire gemslune surface area. The center of the rotatable- platform 53 has a transparent window 51 on which the gemstone 7 is placed The transparent window 51, having a transparent surface area boundaries designed to circumscribe, the periphery of the gemstone 7 placed thereon. A holding device may be required to maintain the placement of mounted stones and to huld a stone in place when the rotatable platform 53 is rotated at high speeds. The platform is circumscribed by a stage light 73. The stage light 73 can be a ring light or array of light emitting diodes to illuminate the undersides of a gemstone 7.
Positioned below the rotatable platform 53 is a second filter assembly 24 with an iris for regulating the light traveling to the transparent window 51 of the rotatable platform 53 from below. Additionally, the assembly accommodates filters and or masks used in refractive index and flaw analysis imaging methods. Positioned below the filler assembly 24 is a light directing means 57 mounted at a 45° angle to the horizontal, traveling through the center point of the light directing means is processing axis 105 which is aligned with the center point of the transparent window 51
When the unitary stage 53 is in the LEVEL position, light data .along
the focal axis 80 incident to gemstone 7 is captured by CCD camera 12
When the unitary stage 59 is moved to the UP position mid the centei point of the light directing means 57 is aligned with that of the fncal axis 80. light is directed by the means 57 along focal axis 80 and into the lens of camera 12. This arrangement allows a view of the bottom or the table side of a gemsione 7.
A light directing means 53 is positioned above the platform at a 45" to the horizontal with its center point along processing axis 105. This configuration allows light from the stone side of the window 51 to illuminate a gemstone 7. The reflected light of light directing means 15 is redirected to the lens of camera 12 when the stage is moved to the DOWN setting, the center point the light directing means 55 is aligned with that of the focal axis 80; This arrangement allows a top view of the stone. When the stage 59 is in its normal position, and by rotating the platform .53, multiple images nf the profile, front and back of UK- gemstone 7 can be taken.
Opposite the. camera side of the stage 59. a diffused light source 102 provides back lighting used in profiling the silhouette of a gemtone 7, used to extract coordinate values from the corners of a gemstone 7 when imaging the periphery. For, example a side image is captured with the stage in the LEVEL position, the top and bottom perspectives obtained in the DOWN and UP positions of stage 59 respectively via light directing means 55 and 57 Referring more particularly to Figure 5, a bottom light assembly includes ring light 90, bottom light 94 and laser light 92. The ring light 90 is a D 55 ring light having a color rendition and an ultra viole component that closely resembles North-Daylight at 5500°K. The circular configuration ensuring consistent application of the light to the periphery of the gemsrone 7. The ring light 90 is used in color, brilliancy and scintillation analysis, and placed in such a manner relative to the stone as to create dark field illumination, (i.e., creating a dark background with respect 10 the gemstone 7 from the camera perspective) . The bottom light 94 can be any dimmable
and diltusible light source, in the preferred embodiment it is a halogen light Bottom light 94 and light 93 are used in clarity analysis Diffused light 93 is placed off to the side, of the processing axis 105 and is u:.cd in conjunction with light 94 to get a reflection of the table with the camera 12 Additionally, bodom light 94 and light 9.3 are used in capturing the morphology of tliK table of a gemstone 7 for cut analysis, the table image is also utilised to accurately measure the polish of the table, its surface characteristics, and match a gemstone 7 through in unique sequence or side images The laser light 92 is used to align a gernstone 7 on the glass window vja LCD display 9, obtain laser scatter, and to measure refraction.
Above the stage. 59 is light source 74 to provide direct lighting of the gemstone 7 useful in observing it;; top portion. Light source 74 can be any dimmable diffused lighl. In the preferred embodiment a halogen or LED light source 14 is utilized. Light 74 is used in clariiy analysis, surface delect detection, culel analysis, color analysis of dnrk stones and pearls and lustre in pearls. Above the light 74 is another filter assembly 23 that can hold a diffuser and one or more filters for blocking light of a preselected frequency. Above the filter assembly 23 is a light source 71 used to profile the girdle, match and calculate the perimeter of the gemstone 7, measuie thr total surface area, and is used in clarity analysis. Right above the halogen light 71 is a canopy (not shown) that lets warm air out without letting outride light to penetrate the inside of the apparatus 5.
CONTROL CIRCUIT
Referring now to Figure 6, control and data acquisition circuit 110 dictates the actuation of the internal motors and light sources of apparatus 5. A DC power supply rectifies the AC line current provided through switch 31, for components of control and data acquisition circuit 110 which require DC power. Control and data acquisition circuit 110 includes relays K1-K13, servo controller 83, servo motors 86, 87, and 120, LCD and LED dnving
circuitry 125, speaker 140, DC fan 61. and AC fan 130.
The relays K1-K13 are selectively actuated to enable the lamp or motor connected thereto by way of data port 16. The servo motors am driven by servo control unit 83 The actuation of motors and lamps is provided by the data processor 15 of local station 8 through an interface of data port 16, preferably the DB-25 COMP port 41. For example, upon reception of an actuation signal from the data processoi 15 for liglt source 102 of apparatus 5, the data port 16 triggers relay K6 to enable light source 102.
Speaker 140 provides audible indicia of the execution of insrmction by apparatus 5. The audible: indicia may be prerecorded descriptive phrases such as "color", "clarity", and "scintillation."
IMAGING METHODS (LEVKL)
Referring now to Figure 7, a first image capture configuration is shown for capturing n first set of images, namely, images A I- A19 It should be noted however, that the image capture procedure, lamp and motor actuation sequence can be altered or truncated to accommodate specific gr.mxioiies 7 such as pearls which may not possess the full range of qualities snr.li as table dimensions, clarity, brilliance etc.
The lights and motors of apparatus 5 are controlled by local staiinn 8, speci6cally apparatus 5 is controlled way of the instruction set of the data processor 15 of local station 8. The preferred sequence and duration of light and/or motor actuation will now be described herein for analyzing a diamond gemstone 7.
At start up, the apparatus 5 is initialized by closing power switch 31. A diagnostic analysis of the lights and motors of apparatus 5 is completed by this data processor 15 of local station 8 including the calibration oi diimmible lights, to desirable intensities, upon satisfaction of this test, indicating all devices as functioning, 9 or monitor (not shown).
At Stan up, ihe laser light 92 is enabled such that a beam of visible light is aligned with processing axis 105 to facilitate UK: placement of a gemstone 7 on rolatable platform 53. Unitary stage 59 is initialized in the. LEVEL position to align rotatabie platform 53 with focal axis 80 The camera 12 is set to the "A" position along focal axis 80 position by x axis linear positioner 49.
A gemstone 7 is prepared for analysis, a cleaning fluid such as alcohol is applied to the gemstone 7 to remove particles and impurities which may interfere with the imaging process Sliding door 29 of apparatus 5 is opened and a gemstone 7 is placed at the center of the translucent window 51 of platform 53 with the guidance of laser light 92 directed therethrough. Sliding door 29 is closed and the gemstone 7 is in position for analysis by appaiittus 5.
Imaging begins by disabling laser light 92. A profile image ol the gemstone 7 (Al) is obtained by ennbling D55 light 90 and light 102, rotatabie platform 53 is rotated to obtain the profile of bezel facets and image (Al) is captured by camera 1? of apparatus 5. The profile image (Al) is communicated from apparatus 5 to the data processor 15 of local stainm 8 for further processing by analysis station 14.
A second image (A2) is obtained for color analysis by disabling light 102, light 90 remains enabled. The resulting image of gemslone 7 is captured with camera 12. Similarly, the second image (A2)is forwarded for further processing to analysis station 14. The process of obtaining profile, and color images (Al) and (A2) is repeated dependent of the. cut of the. diamond as determined by the data processor 10 of local station 8.
For example a third image is obtained by rotating the platform 53 by a preset amount, the degree of rotation determined by the instruction set of the data processor 15, enabling light 102, light 90 remains enabled and another image of the profile (A3) is captured by camera 12..

Similarly, a fourth image (A4) is taken by again disabling light 102, light 90 remains enabled and the image is captured by camera 12 for color analysis.
For a round brilliant cut diamond the first and second image:, (Al. A2) are captured from eight locations determined by the preselected rotation of platform 53 resulting in sixteen separate profile and color images (Al-A16). These images are used in cut analysis and for color measurement.
Upon completion of the profile and color imaging , light 102 is disabled and fluorescent light 64 is enabled to obtain a fluorescence image A17 which is used together with the last captured coloi and profile image of sei (Al A16) to check foi fiuoiescence levels, these images may rangi: from (Al) and (A2) to (A15) and (AJ6) depending on the cut of the diamond. As can he appreciated image (A17) is taken only fur thoseg emstones with fluorescent qualities.
Image (A18) is captured by disabling all lights, and enabling from light 77 to image the front of a gemstone 7. image (A18) is captmcd by camera 12. The platform 53 is rotated 180° and another image (A19) is captured. Images (A18) and (A19) are used to gauge external surface flaws on the- sides of a diamond, faceting and the quality of the girdle
1. STAGE UP
Referring now to Figure 9, a second image captun- configuration is shown for capturing a second set of images, namely, images A21 A2-1 The second stage setting is accomplished by moving the stage. 59 up along processing axis 105 by way of y-axis linear positioner 87. Stage 59 is moved up such that the center of light directing means 57 is alignc.d with focal axis 80 and platform 53 is in the UP position. The camera 12 is moved from position "A" to position "B" along focal axis 80 by the linear positioner 49.
Brilliance and scintillation image (A21) is obtained by enabling D55 Light 90. Image (A21) used for brilliance, scintillation and matching analysis
is captured by camera 12
Girdle image (A22) is captured by camera 12 by disabling Light 90 and enabling light 71 to capture an image (A22) for girdle measurements.
Table and luster image (A23) is captured by camrra 12 by disabling light 71 and enabling light 92 and 93 are enabled, image (A23) is capiured for use in luster analysis and to determine the shape and size of the table for cut and matching analysis.
Laser scatter image (A24) is captured by camera 12 by disabling lights 92 and 93 and enabling laser light 94 to capture the internal laser scaiter in image (A24). This is done to replicate the image capture used by Gem Print, a proprietary system, fnr extending support services and is not essential to this invention. Gem Print uses the laser scatter pattern to match gemstonc 7 to stones in an existing pixel data base. All lights are disabled prior to the initiation of the third stage setting.
II. STAGE DOWN
Referring now to Figure 8, a third image capture configuration is shown for capturing a third set of images, namely, images (A25 and A2G). In the third stage setting stage 59 is moved clown along processing axis 105 by way of y-axis linear positioner 87. The stage 59 is moved down such that the center of light directing means 55 is aligned with focal axis 80 and platform 53 is in the DOWN position. The camera 12 remains in position "B" along the focal axis. A combination of lights, namely 74, 71 and 73 are ned on to gel the best image. (A25) which is used to examine the culet, table facets and surface features. At this point the gemstone 7 is removed from the platform 53, all lights are disabled.
FLAW ANALYSIS/MATCHING
Prior to flaw analysis, gemstone 7 is removed from the apparatus S and thoroughly cleaned For flaw analysis, image (A26), one of two prefened
procedures may be used. In the first procedure, a gemslone 7 is placed on a glass plate, with its underside etched to diffuse light, a small amount of high viscosity immersion oil is dispensed at the center of the plate and a gcmstone 7 is placed on the plate in contact with the oil. The plate is placed above the translucent window 51 and lights 92, 93 and 73 are turned on to utpture imagc (A26) for internal flaw analysis.
Another approach is to totally immerse a diamond in a small crucible with a diffused base and walls The crucible is placed on platform 53 for capturing image (A26) with camera 12. This method yields a slightly better image quality. For small flaws, 5 microns or larger, the lens of camera 12 is set to higher magnification and multiple images may be taken by scanning the gemstone 7.
This completes a step by step procedure for capturing images used in the grading of a diamond. It should be clear that apparatus 5 can be used to obtain other images from the setup described above.
SOFTWARE PROCESSINC
Referring now to Fignrrs 10A-10C, there is shown an example of the procedure by which the images captured by imaging apparatus are. obtained and organized, and more particularly, the manner in which inoidenl light data is utilized in the grading and identification of gemstoncs. At start-up, atcp 200, the processing parameters, constants, and counters of local processni 10 are initialized and the lighting elements of the imaging apparatus arc calibrated to ensure consistency in lighting levels. Each gemstortc analyzed by the apparatus produces a set of pixel data images in accordance with the invention. The images for each gemstone analyzed are stored in a unique analysis folder in the memory of local station 8. The folder organizes the pixel data images into files as captured by the apparatus 5 along with a text file that contains information on ownership, eventual results of the analysis, an appraisal report and other pertinent information. The texl files may be
created in part by manually entered information via an appropriate user interface of apparatus 5.
Image data in the file folder of local station 8 is analyzed by the data processor 21 of the analysis station 14. In the preferred embodiment, the file folder or set of image and text files are sent to the analysis station M for processing and compilation in the analysis station database: The fold p. r and its contents are backed up for data security, thereafter, contents of thr fuldei are analyzed to prepare an appraisal report based on the communicated pixel images of analyzed gemstones.
Referring now to Figure 10A, in step 202 the local station 8 creates the unique file folder for the storing of gf-mstone appraisal data. The illustrative procedures described herein utilize diamond gemstones Beginning with step 204, the cut of the gemsione is determined by defining points about the gemstone peripbery The profile of a di.unond is. a convex set of pixels of low gray scale, values against a background of pixels lighter in color. A change from a light to a darker pixel identifies .1 pixel to be on the boundary. Knowledge of the shape of a diamond is utilized with tin-, pixel gray scale values to identify corner points. Thus, in diamond analysis for example, the points define the maximum dimension of the table, girdle and culer. The value of pixels per millimeter(mm) is known and carats per cubic millimeter is assigned interactively and is roughly .00173801. As such, the diuu-.nsion of the gemstone is determined by the processor 10 of local station 8 by performing a plurality of geometric calculations based on the dclmed constants and obtained gemstone coordinates. Proceeding to step 206, the first cut analysis extracts coordinate data for the corners via the profile image (Al) The gemstone size coordinates are stored within a file of rhe folder. Next, in step 208 the gemstone size proportions are determiiu-.d by geometric calculations utilizing the obtained coordinate points. A counter, steps 210 and 212, repeats this process for obtaining images necessary to analyze fancy cut gemstones, up to a maximum of eight for round fancy cut stones. The
process is repented until all profile images are processed.
The cut analysis continues in step 214 by defining maximum girdle point about the gemstone periphery, the coordinates are saved in step 216, and girdle size and perimeter arc calculated in step 218
Referring now lo Figure 10B, the final cut analysis includes step 220 for defining table coordinates Since the morphology of the table of the-round brilliant cut generally follows an octagonal shape, a morphological algorithm is employed 10 find the corner points. For certain fancy cuts and where necessary, a cursor is used to manually mask the corner points of a table. Step 222 permits the operaror to enter this data manually via step 224. The table coordinates are stored within a file of the folder stored within the memory of local station 8. The coordinate data is further analyzed as outlined flowchart in steps 230 and 232 to calculate the girdle size, table width, table height, culet height, pavilion angle, table angle, girdle thickness and various ratios associated with cut analysis and gemstone appiaisal practices known to those, skilled in the art. Cluster analysis is then used to assign a cut grade based on certain proportional attributes. A database including diamonds of different proportions and associated cut grades are. used in cluster analysts. The cluster analysis assigns a cut grade based on the proximity of a gemstone to a cut grade in multidimensional space.
Gemstone color analysis begins with step 234 and is done by obtaining average R.G.B. (red, green, blue) values from color images (A2, A3, A6....) in the image pixel region delineated by the girdle and the table facets by sampling the color of a smaller region a more predictable and accurate color reading is obtained. Steps 236 and 238 provide the option of manually entering the R.G.B. values. The R.G.B. image sets are stored within a file of the gemstone analysis folder, step 240. The nurnbei of R.G.B. images taken is determined by a counter in steps 242 and 244.
Diffraction of light caused by such geinstones as diamonds skews the R.G.B. color readings by misrepresenting the body color of the gemstone.
Furthermore, the diffraction of the light energy into sprclral components increases a standard error in the R.G.B. average. The software of the data processor 21 of analysis station 14 compensates for this by removing outlier value images from the statistical analysis. Thereafter, an average of the R.G.B. pixel intensity values is calculated in step 246.
Referring now lo Figure 10C, average R.G.R values are additionally obtained from the gems tone color image under ultra violet rndintton vin step 248, image (A17) The difference between the average R.G.B. value without ultra violet radiation and under ultra violet radiation are used to determine the. presence of fluorescence in step 250. Fluorescence devalues diamonds. This analysis is done using a statistical model. Likewise, K.G. B. values from the color images are transformed to C.I.E., L.A.B., and J,.U V. omirdin.-Ue.s-Before assigning a color grade, flaw analysis is performed in step 252. Flaw identification may be performed manually as illustrated by steps 254 and 256.
A processing algorithm is used for flaw analysis. A combination of thresholding and filters is used to highlight internal flaws, inclusions, pin points etc. The size and location of these flaws is measured. Internal flaws are identified by the algorithm and saved in H file (A27). A clarity grade is assigned based on the size of the flaws compared to the overall area of the lace of a stone weighted by its location; flaws near and within the hound.mes of a table diminish the value more than flaws that are farther away from the surface and closer to the girdle area. Proceeding to step 258 the flaw data is stored within a file of the analysis folder. Flaws are identified and maiked and a gemstone image file (A28) is created in step 262. Images (Ay), (A10), (A25), and (A26) are analyzed in step 260 for determining gemsione brilliance, scintillation, and polish analysis. This approach is taken to gel as much information as possible to ascertain if the system has analyzed the same gemsione.
To do brilliancy analysis, average R.G.B. values are extracted from the
brilliancy image using a processing algorithm C.I.E., standard L.A.B., and
L.U.V. tri-stiinulus coordinates are calculated adjusting for incident light
intensity. A ratio of the average gray value and a standard is used to
calculate brilliancy. Scintillation is measured by first thresholding the image
and then calculating the total number of pixels that have an average gray
scale value above the threshold level. A ratio of these pixels divided hy the
total number of pixels on the face of a stone arc used to measure
scintillation. The higher the number, the greater the scintillation value
Polish of the table is determined by extracting the average R.G.B values from
the table image A23. The average R.G.B. values arc adjusted foi the incident
light. A polish grade for the table is assigned by comparing the adjusted
R.G.B. values to a standard. Once the flaw, brilliance., scintillation, and
polish analysis are completed a search is done of the datr.base of analysis station 14 to determine the existence of a record which would indicate any prior analysis of the geimtone. or an indication whether the gemstoiir. has been included in a lost or stolen record field of the database for mair.liing A hierarchical search technique is used to reduce search time considerably in steps 264 and 266- If more than one gemstone is identified by the search, comparison is made by the data processoi to establish a peifuct match. Ideally, only after this step is completed, a cluster or linear discriminant model is used to assign color based on tri-stimulus coordinates, weight of a diamond, flaws, and fluorescence in step 268. For newly cut diamonds, searching the database is obviously unnecessary. Results of analysis are saved and a report is printed or sent to the local station 8 which requester! the analysis.
In addition to evaluating gemstones, the analysis station 14 matches the characteristics of the analysed gemstones 7 to characteristics of yemstonns previously analyzed by the apparatus 5 and stored in the database. Moreover, the database can be queried to inventory gemstones 7 possessing a certain characteristic and/or price range as the database maintains current market

prir.e information used in the appraisal of gemstones. The- analysis station J4 can perform grading, matching, identification, sorting, and appraisal functions independenltly or in any specified combination and communicate these reports as a multimedian presentation to local terminals.
The terms and expressions which have been employed are used as terms of description and not of limitation. There is no intention in the- use of such terms and expressions uf excluding any equivalents of the features shown and described or portions thereof. It is recognised, however that various modifications are possible within the scope of the invention as claimed.





We Claim:
1. Apparatus for grading and identification of a gemstone comprising:
a housing(2);
a platform (53) mounted in said housing for supporting a gemstone;
first means (9) disposed within said housing for illuminating a gemstone
supported by said platform;
means (49) for displacing said platform in said housing;
an electronic camera (12) mounted in said housing for viewing a gemstone on
said platform, said camera being adapted for generating electronic image signals
corresponding to a physical characteristic of the gemstone;
an electronic data processor (10) operatively connected to said displacing means
and said electronic camera, said electronic data processor being programmed with
an instruction set for controlling said displacing means and said electronic
camera, and for receiving and storing the electronic image signals.
2. Apparatus as claimed in claim 1 wherein said platform is mounted on an axis, and
said displacing means comprises:
means for moving said platform along an axis thereof; and means for rotating said platform about said axis.
3. Apparatus as claimed in claim 1 wherein said first illuminating means comprises;
a first light source disposed beneath said platform; and
a second light source disposed above said platform.
4. Apparatus as claimed in claim 3 comprising:
a first light directing means disposed between said first light source and said
platform; and
a second light directing means disposed between said first light source and said
platform; and
a second light directing means disposed between said second light source and said
platform.
5. Apparatus as claimed in claim 1 wherein said platform comprises a transparent portion for supporting the gemstone, whereby light emitted from said illuminating means is permitted to impinge on the gemstone.
6. Apparatus as claimed in claim 1 comprising display means operatively connected to said electronic data processor for displaying images of the gemstones based on the electronic image signals.
7. Apparatus as claimed in claim 1 comprising means for displacing said camera along an axis that is perpendicular to the axis of said platform.
8. Apparatus as claimed in claim 1 comprising: a light filter; and
filter support means disposed between said camera and said platform for supporting said light filter.
9. Apparatus as claimed in claim 8 comprising filter replacement means for inserting and removing said light filter.
10. Apparatus as claimed in claim 1 comprising a motor driven fan for circulating air inside said housing.
11. Apparatus as claimed in claim 1 wherein said housing comprises an opening and a dust filter disposed in said opening.
12. Apparatus as claimed in claim 1 further comprising an ultraviolet light source disposed in said housing for illuminating the gemstone with ultraviolet light.
13. Apparatus as claimed in claim 1 wherein said electronic data processor generates a data file containing information on the physical characteristic of the gemstone based on the electronic image signals and the electronic data processor comprises a data storage device for storing the data file for later retrieval.
14. Apparatus as claimed in claim 13 wherein said electronic data processor comprises means for retrieving the data file from the data storage device and communicating said data file to a second data processor whereby the second data processor generates an appraisal report relative to the gemstone.
15. Apparatus as claimed in claim 1 comprising second illumination means disposed within said housing for backlighting the gemstone on said platform relative to said electronic camera.
16. Apparatus as claimed in claim 15 comprising a third illumination means disposed within said housing for frontlighting the gemstone on said platform relative to said electronic camera.
17. A method for grading a gemstone, the method comprising the steps of: providing an apparatus according to claim 1 wherein the electronic camera is a CCD camera:
placing the gemstone the platform in said apparatus at a first position within an
area substantially free of light;
providing a translucent portion in said platform circumscribing the gemstone
periphery;
positioning a data responsive element of a the CCD camera having a focal axis
aligned with said first position of the platform;
linking the CCD camera to a the electronic data processor operating an instruction
set;
illuminating the bottom side of the gemstone through the translucent platform
portion from a position beneath the platform;
illuminating the gemstone from a lateral side thereof in the direction of the light
responsive element of the CCd camera;
rotating the platform about its central axis according to said data processor
instruction set; and
capturing the incident light data with the CCD electronic camera and storing it in
said memory as an image data set.
18. A method for grading a gemstone the method comprising the steps of:
providing an apparatus as claimed in claim 1 wherein the electronic camera is a
CCd camera;
placing the gemstone on the platform in said apparatus at a first position within an area substantially free of light, and providing the platform with a translucent portion therethrough underlying said gemstone and circumscribing the gemstone periphery;
positioning the data responsive element of the CCD camera having a focal axis
aligned with said first position of the platform, the CCD camera operably linked
to the electronic data processor opearing an instruction set, the electronic data
processor storing captured light data in a memory device;
illuminating the gemstone with a D 55 light source from beneath the translucent
portion of said platform; and
capturing the incident light data with the CCD camera and storing it in said
memory as an image data set.
19. The method as claimed in claim 18 wherein the D 55 light source is a circular ring light.
20. The method as claimed in claim 18 including the step of translating the CCd camera along the focal axis to positions defined by the instruction set of the data processor.
21. A method for grading a gemstone, the method comprising the steps of: providing an apparatus as claimed in claim 1, wherein the electronic camera is a CCD camera;
placing the gemstone on the platform in said apparatus at a first position within an area substantially free of light, providing in the platform a translucent portion for supporting the gemstone and circumscribing the gemstone periphery; positioning a data responsive element of a CCD camera having a focal axis aligned with said first position of the platform, the CCD camera operably linked to the electronic data processor operating an instruction set and adapted to travel from a fist position to a second position along the focal axis, the electronic data processor storing captured light data in a memory device; moving the platform upwardly with respect to the focal axis; positioning a refractor element having an angle of refraction in alignment with the focal axis;
moving the CCD camera towards the refractor element along the focal axis to the
second position.;
illuminating the gemstone from a position beneath the translucent portion of the
platform; and
capturing the incident light data redirected by the refractor element with the CCD
camera and storing it in said memory as an image data set.
22. The method as claimed in claim 21 wherein the distance between the first and second camera positions on the focal axis is equivalent to the distance traveled the platform upwardly from the focal axis.
23. A method for grading a gemstone, the method comprising the steps of: providing an apparatus as claimed in claim 1, wherein the electronic camera is a CCD camera;
placing the gemstone on the platform in said apparatus, said platform having a
translucent portion thereon at a first position within an area substantially free of
light, the platform translucent portion circumscribing the gemstone periphery;
positioning the data responsive element of the CCD camera having a focal axis
aligned with said first position of the platform the CCD camera operably linked to
a data processor operating an instruction set and adapted to travel from a first
position to a second position along the focal axis, the data processor storing
captured light data in a memory device;
moving the platform upwardly with respect to the focal axis;
positioning a refractor element having an angle of refraction in alignment with the
focal axis;
moving the CCD camera towards the refractor element along the focal axis to the
second position;
illuminating the gemstone from a position beneath the platform;
capturing the incident light data redirected by the refractor element with the CCD
camera and storing it in said memory as an image data set;
disabling the illumination from beneath the platform;
illuminating the gemstone from above the platform;
capturing the incident light data redirected by the refractor element with the CCD
camera and storing it in said memory as an image set;
disabling the illumination from beneath the platform;
illuminating the gemstone from a second light source from beneath the platform;
and
capturing the incident light data redirected by the refractor element with the CCD
camera and storing it in said memory as an image data set.
24. A method for grading a gemstone, the method comprising the steps of:
providing an apparatus as claimed in claim 1, wherein the electronic camera is a
CCD camera;
placing the gemstone on the platform in said apparatus at a first position within an area substantially free of light, the platform having a translucent portion thereon circumscribing the gemstone periphery;
positioning the data responsive element of the CCD camera having a focal axis
aligned with said first position of the platform, the CCD camera operably linked
to a data processor operating an instruction set and adapted to travel from a first
position to a second position along the focal axis, the data processor storing
captured light data in a memory device;
moving the platform downwardly with respect to the focal axis;
positioning a light redirecting element having an angle of redirection in alignment
with the focal axis;
moving the CCD camera towards the refractor element along the focal axis to the
second position;
illuminating the gemstone from simultaneously with two light sources from above
the platform;
illuminating the gemstone from a side position directed towards the data
responsive element of the CCD camera; and
capturing the incident light data routed by the light redirecting element with the
CCD camera and storing it in said memory as an image data set.
25. The method as claimed in claim 24 wherein the step of placing the gemstone on the platform translucent portion further comprises centering the gemstone on the translucent portion with a laser light source passing through the center of said translucent portion.


Documents:

abstract.jpg

IN-PCT-2000-00324-DEL-Claims-(29-10-2005).pdf

in-pct-2000-00324-del-form-1.pdf

in-pct-2000-0324-del-abstract.pdf

in-pct-2000-0324-del-assignment.pdf

in-pct-2000-0324-del-claims.pdf

in-pct-2000-0324-del-correspondence-others.pdf

in-pct-2000-0324-del-correspondence-po.pdf

in-pct-2000-0324-del-description (complete).pdf

in-pct-2000-0324-del-drawings.pdf

in-pct-2000-0324-del-form-2.pdf

in-pct-2000-0324-del-form-3.pdf

in-pct-2000-0324-del-form-5.pdf

in-pct-2000-0324-del-gpa.pdf

in-pct-2000-0324-del-pct-101.pdf

in-pct-2000-0324-del-pct-210.pdf

in-pct-2000-0324-del-pct-304.pdf

in-pct-2000-0324-del-petition-others.pdf


Patent Number 246166
Indian Patent Application Number IN/PCT/2000/00324/DEL
PG Journal Number 08/2011
Publication Date 25-Feb-2011
Grant Date 17-Feb-2011
Date of Filing 10-Nov-2000
Name of Patentee IMAGESTATISTICS INC.
Applicant Address 5869 OVERBROOK AVENUE, PHILADEPHIA, PENNSYLVANIA 19131, U.S.A.
Inventors:
# Inventor's Name Inventor's Address
1 AGGARWAL, LALIT K. 5869 OVERBROOK AVENUE, PHILADEPHIA, PENNSYLVANIA 19131, U.S.A.
PCT International Classification Number G01N 21/00
PCT International Application Number PCT/US99/11500
PCT International Filing date 1999-05-25
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 09/085,797 1998-05-28 U.S.A.