Title of Invention	"SYSTEM AND METHOD FOR TRADING IN PRECIOUS GEMSTONES"
Abstract	A system for trading in gemstones, which is having a flat table defining a longitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet The system comprises a plurality of user terminals for capturing digital lifelike color images of a gemstone, each user terminal capable of generating the same standard portfolio of digital lifelike color images of a particular gemstone for enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards.

Title of Invention

"SYSTEM AND METHOD FOR TRADING IN PRECIOUS GEMSTONES"

Abstract

A system for trading in gemstones, which is having a flat table defining a longitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet The system comprises a plurality of user terminals for capturing digital lifelike color images of a gemstone, each user terminal capable of generating the same standard portfolio of digital lifelike color images of a particular gemstone for enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards.

Full Text	- 1 - FIELD OF THE INVENTION This invention relates to a system and method for trading in precious gemstones. gemstone examination apparatus for examination of gemsiones. a method for obtaining a pair of complementary digital left and right images of an object for displaying a stereoscopic image thereof, and a method for displaying a visually continuously movable image of an object at a computer terminal. BACKGROUND OF THE INVENTION Trade in precious gemstones in general - and diamonds in particular (hereinafter referred to gemstones) is based on evaluations by trained professionals who carefully scrutinize a aernstone with their naked eve and/or usins a X10 magnifying glass, or a microscope. A professional evaluation of a gemstone depends on quantifiable parameters such as weight, color, clarity in terms of its imperfections, polish, cut and relative proportions of a gemstone's different portions, and also on its inherent beauty in terms of its brilliance in the way that it reflects light. A gemstone's proportions can be calculated from a three dimensional wire frame representation of a gemstone. for example, as implemented in calibrated optic digital image acquisition systems commercially available from Ogi Ltd. Israel; Sarin Ltd. Israel; and others. Certification of a gemstone can be obtained from one or more internationally recognized bodies, for example. The Gem Trade Laboratory of the Gemological Institute of America. Other certification can be in the form of a Gem Certificate as illustrated and described in US Patent 5.899.503 Gemstones are now traded over the Internet at various Websites including inter alia vvwvv.gemkey.net, www.diamond.net. and www.poJyaon.com. The Websites act as virtual market places, and maintain inventories of gemstones for -2- sale including details of the above-mentioned parameters for each gemstone together with its asking price per carat. In addition, gemstones with similar specifications can be put up for sale in clusters, A potential, buyer of a gemstone can search an inventory of gemstones for sale by specifying search parameters, for example, carat, asking price per carat, and the like. Assuming that the inventory lists one or more gemstones, or clusters of gemstones, meeting his search criteria. the buyer is presented with same. The buyer then enters a purchasing order in respect of one or more of the items in which he is interested in which are then sent to him for evaluation, and which are returned to the seller if the buver cannot reach an agreement with him. Thus, whilst trade in gemstones has been somewhat streamlined, there still remains a considerable undesirable movement of stock which could otherwise be avoided if a potential buyer of a gemstone, or a cluster of gemstones. could remotely and independently substantiate a seller's evaluation of a gemstone and in particular its market value. Registration markings are now inscribed on gemstones for identification purposes. The most common type of registration marking includes letters and numbers constituted by a series of spaced apart light diffusing segments on one of a gemstcne's flat, polished surfaces, find typically either its table or its girdle. This type of marking uses a 0.5 ?n high segments and is about 50um long so as to be invisible to the naked eye. thereby not detracting from a gemstone's beauty. Detection of a gemstone's registration marking requires at least a X200 magnification and scanning either a gemstone's entire table or girdle, and is a time consuming and cumbersome process. SUMMARY OF THE INVENTION Trade in gemstones involves transactions between "a seller of a gemstone " and "a potential bin-er of a gemstone". however, a seller in one transaction may be a potential buyer in another transaction by virtue of the nature of trade in gemsiones. Therefore, the present specification employs the specific terms "o seller of a gemstone" and "a potential buyer of a gemstone". and sometimes the -3- generic term " a user" as most appropriate within the context of the description. Moreover, the present specification pertains to trade in single gemstones only, however, it should be understood that the present invention equally applies to trade in clusters of similar gemstones. Also, the present specification pertains to trade in so-called circular cut gemstones, however, it should be understood that the present invention also equally applies to trade in other shaped gemstones. In accordance with a fust aspect of the present invention, there is provided a system for trading in gemstones. each gemstone having a flat table defining a Ipngitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet, the system comprising a plurality" of user terminals for capturing digital lifelike color images of a gemstone. each of said user terminals being capable of generating the same standard portfolio of digital lifelike color images for a particular gemstone, thereby enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards. In accordance with a second aspect of the present invention, there is provided a method of trading in gemstones. the method comprising the steps: (a) .providing a data storage device with a plurality of portfolios of digital lifelike color images of gemstones each enabling a potential buyer of a gemstone to independently evaluate its market value from its associated portfolio of images in accordance with internationally recognized standards; and (b) enabling one or more potential buyers of gemstones remote access to the data storage device whereupon a potential buyer of a gemstone can peruse through the portfolio of images of a particular gemstone which he is contemplating to purchase. A system and method for trading in precious gemstones in accordance with the present invention necessarily includes the generating of a standard portfolio of digital, lifelike color images for a particular gemstone whereby a potential buyer of a precious gemstone can independently, on the one hand, determine iis trade recognized quantifiable parameters and. on the other hand, appreciate its beauty for -4- evaluating its market value as if he was physically scrutinizing the gemstone itself. The necessity that each and every user terminal of the system will generate substantially identical portfolios for the same gemstone isxrucial to the trading of gemstones since otherwise potential buyers will not be able to implicitly rely on a portfolio when contemplating whether he wants to purchase a particular gemstone. The system and method of the present invention can either be implemented on a server based intranet or on a business-to-business Website maintaining an inventory of portfolios of images of gemstones for sale. In both implementations, a potential buyer can preferably conduct a telephone conversation with a seller of a gemstone to instruct him to show him on-line particular views of a gemstone that he is interested in purchasing. The imaging of a gemstone is particularly difficult due to its highly polished surfaces reflecting light in such a manner that its interior is obscured for example, as in photographs for advertising purposes which accentuate a gemstone's beauty but do not reveal its imperfections. Against this, photographs of a gemstone's imperfections are normally "lifeless " in the sense that they are devoid of any of the gemstone's beauty, for example, as obtainable by apparatus for examining gemstones illustrated and described in US Patent 4.906,083 to Sattler which employs dark field illumination or polarized filters. The present invention overcomes the difficulties of imaging a gemstone by on the one hand, effectively shielding a gemstone from ambient light which would otherwise cause two user terminals to generate two different portfolios of images depending on their local environments and; on the other hand, so-called "bathing" a gemstone in diffused artificial white light in such a balanced manner such, that captured images arc neither too brilliant nor too lifeless. Moreover, at least some of the images are so-calLed "'floating' images of uniform background and illumination, and which do not include discernible -contours of a transparent gemstone specimen holder employed for mounting a gemstone during the capturing of images thereof. A gemstone's portfolio of digital. lifelike, color images includes one or more still images of its table, its girdle, and the like, and also preferably includes -5- one or more movable images of a gemstone's surface, images suitable for displaying a stereoscopic image of a gemstone using any one of a number of commercially, available systems, for example, the Simuleyer™ stereoscopic viewing system available from Neotek Inc.. a three dimensional representation of a gemstone viewable in three dimensional viewing space in a manner similar to that described in US Patent 5.793.372. an image of a gemstone's registration marking, and a Gem Certificate including at least one representation of a gemstone with its imperfections indicated for the purpose of evaluation by a potential buyer. The movable images may include one or more of the following images: First, a so-called tillable image of a gemstone's surface which may be either its table, its girdle orjtsjpavilion. Second, a rotatable image of a gemstone's surface which may be either its table or its pavilion. And lastly, a precession-like movable image of a geinstonc's table as the gemstone undergoes a superimposed combination of the movements .for the so-called tillable image of its table together with die semstone's rotation about its longitudinal axis. The movable images may be true video streams, or series of computer rendered animated images generated on-the-fly at a potential buyer's computer terminal from bit map information downloaded thereat. The movable images of a gemstone are important supplements to the still images sirice they can better provide a sense of the location and the depth of an imperfection in a gemstone. and furthermore they can reveal imperfections which may otherwise be concealed behind a gemstone's surface blindingly reflecting light. The images can also be manually processed by a seller to include Areas of Interest (AOls) graphically indicating the locations of a gemstone's imperfections for facilitating a potential buyer's awareness of same, and therefore improving the accuracy of his evaluation of the gemstone's market value. The images of a gemstone, and especially those which include AOls, can be readily incorporated in a Gem Certificate issued by an internationally recognized body, for example, the above mentioned Gem Trade Laboratory. Also, one or more of the images may include a color chart for facilitating a potential buyer's determination of a gemstone's color. -6- In accordance with a still yet another aspect of the present invention, there is provided a method for displaying a visually continuously movable image of a gemstone at a computer terminal remote from a database, the method comprising the steps of: (a)downloading bit map information regarding a gemstone from the database to the computer terminal; (b)generating from the downloaded bit map information at the computer teiminal an on-the-fly computer rendered animated image of the gemstone from a particular line of sight directed toward the gemstone: and (c)refreshing the computer rendered animated image of the gemstone from different lines of sight directed toward the gemstones as indicated by a potential buyer of the gemstone at his computer terminal thereby displaying a series of animated images of the gemstone perceived as a visually continuously movable image by the potential buyer. The method for displaying a visually continuously movable image of a gemstone according to the present invention at a potential buyer's computer terminal overcomes latency and bandwidth problems involved in transmitting video streams, for example, over the Internet. The visually continuously movable image can be of a particular surface of a gemstone, for example, its table, or alternatively. it can be of a three dimensional representation of a gemstone. The visually continuously movable image of a gemstone's table can be a tillable image, a rotatable image, or a precession-like movable image. In the case of a tillable image of a gemstone's surface, each computer rendered animated image I(n) displayed on a potential buyer's computer terminal is constructed in accordance with the relationship I(n) = pI(first) + (1-p) I(last) where 0 -7- the last still image such that the two directions define a plane therebetween and intersect at an acute angle a- In the case of a rotatable image of a gemstone's surface, each computer rendered animated image I(rot) displayed on a potential buyer's computer terminal is constructed m accordance with the relationship; I(rot) where pixel coordinates In the case of a visually continuously precession-like movable image of a gemstone's surface, each computer rendered animated image I(z) displayed on a potential buyer's computer terminal is constructed in accordance with the relationship I(z) = pI[rot(fwst)] + (l-p)I[rot(last)] where 0 I(rot) where pixel coordiates In the case of a three dimensional representation of a gemstone viewable in three dimensional viewing space, each computer generated animated image displayed on a potential buyer's computer terminal is constructed by displaying a wire frame representation of the gemstone on the computer terminal in accordance with a particular line of sight directed toward the gemstone, and then separately texturing each of the representation's facets in accordance with the relationship: F(i)=Sp(j)F(ij) where Sp(j)2=l for j=l to n different textures of the same facet F(i) each taken from a different line of sight in accordance with a particular line of sight directed toward the gemstone, and p(j) are directional cosines of the line of sight in a predefined Cartesian coordinate system. In accordance with a still yet another aspect of the present invention, there is provided a method for obtaining a pair of complementary digital left and right s::Il -8- images of a gemstone for use in displaying a stereoscopic image thereof, the method comprising the steps of: (a) mounting a gemstone in the field of view of a digital image acquisition device; (b) acquiring a left image of the gemstone; (c) displacing the gemstone in the image acquisition device's field of view; and (d) acquiring a right image of the gemstone. A binocular microscope, for example, as illustrated and described in aforementioned US Patent 4,906.083 enables a user to naturally perceive a stereoscopic image of a gemstone. In a similar manner, a pair of image acquisition devices can be employed for acquiring epipolar left and right still images of a gemstone, such images being essential so as to preclude a blurred stereoscopic image. The method of obtaining a pair of complementary left and right images of the present invention precludes the need for a pair of digital image acquisition devices and can be readily effected using the gemstone imaging device of the present invention. The displacement of the gemstone within the image acquisition device's field of view may be either a translation by a distance substantially equal to the separation of the eyepieces of a binocular microscope, or the gemstone can be both translated and rotated between two extreme positions equidistanced with respect to the image acquisition device's optical axis, in which positions the gemstone's longitudinal axis defines two directions which define a plane and intersect at an acute angle a. BRIEF DESCRIPTION OF THE DRAWINGS In order 10 understand the invention and lo see how it may be carried out in practice, preferred embodiments will now be described, by way of non-limiting examples onh. with reference to the accompanying drawings, in which similar pans are likewise numbered and in which: -9- Fig. 1 is a pictorial representation showing an Internet based system for trade in precious gemslones in accordance with the present invention: Fig. 2 is a pictorial representation showing a user terminal of the system of Figure 1 including a gemstone imaging device and a computerized viewing station: Fig. 3 is a pictoria] exploded representation showing .the gemstone imaging device of Figure 2: Fig. 4 is a pictorial transverse cross section representation showing the gemstone imaging device of Figure 2 along line IV-IV therein; Figs. 5A and 5B are pictorial representations showing two positions of a gemstone bearing carriage holding a first type of a gemstone specimen holder: Fig. 6 is a pictorial longitudinal cross section representation of the first type of gemstone specimen holder along line VI-VI in Figure 5A; Fig. 7 A is a pictorial representation showing the first type of gemsione specimen holder mounting a gemstone with its table uppermost; Fig. 7B is a pictorial representation showing a near full screen size floating image of the gemstone's table as captured by the user terminal when the gemstone is mounted as shown in Figure 7A; Fig. 8A is a pictorial representation showing the first type of gemstone specimen holder mounting a gemstone with its cullet uppermost; Fig. 8B is a pictorial representation showing a near full screen size floating image of the gemstone's cullet as captured by the user terminal when the gemstone is mounted as shown in Figure 8A: Fig. 9A is a pictorial representation showing the first type of gemstone specimen holder mounting a gemstone with its pavilion uppermost; Fig. 9B is a pictorial representation showing a near full screen size floating image of the gemstone's pavilion as captured by the user terminal when the gemstone is mounted as shown in Figure 9A; Fig. 10A is a pictorial side representation showing the first type of gemstone specimen holder rnouming a gemstone with opposite portions of its girdle being uppermost and lowermost; -10- Fig. 10B is a pictorial representation showing a near full screen size floating image of the gemstone's girdle as captured by the user terminal when the gemstone is mounted as shown in Figure 10A; Figs. 11A and 1 1.B are pictorial representations showing a second type of a gemstone specimen holder for enabling the capturing of a rotatable image of a gemstone's table; Fig. 12 is a pictorial representation showing of the second type of gemstone specimen holder for enabling the capturing of a rotatable image of a gemstone's pavilion; Fig. 13 is a pictorial representation showing a third type of gemstone specimen holder for enabling the capturing of an image of a gemstone's registration marking inscribed on its table; FIH. 14 ia a pictrial representation chowing a close-up view of the, illumination of the gemstone's table, and its imaging: Fig. 15 is a pictorial representation showing the scanning of the gemstone's surface for locating the registration marking inscribed thereon; Fig. 16 is a pictorial representation showing a fourth type of gemstone specimen holder for enabling the capturing of an image of a gemstone's registration marking inscribed on its girdle; Fig. 17A is a pictorial representation showing a fifth type of gemstone specimen holder for enabling the capturing of images for generating a three dimensional wire frame representation of a gemstone: Fig. 17B is a top view of the gemstone specimen holder of Figure 17A: Fig. 18 is a pictorial representation showing a graphic user interface for the preparation of a pair of complementary left and right still images of a gemstone's table for generating a stereoscopic image thereof for display on a computerized viewing station of the system of Figure 1; Fig. 19A is a top view a back illuminated silhouette of a gemstone; Fig. 19B is a pictorial representation of a three dimensional wire frame being superimposed onto an image of a gemstone: - 1 1 ~ Fig. 20 is a schematic representation showing the rotational transformation of an image for rendering visually continuously rotatable and precession-like images of a gemstone; Fig. 21 is a pictorial representation showing a graphic user interface of a gemstone's portfolio of digital, lifelike, color images as viewed by a potential buyer; and Fig. 22 is a pictorial representation showing a Gem Certificate of a gemstone. DETAILED DESCRIPTION OF THE DRAWINGS With reference to Figure 1, an Internet based system 1 for trade in precious gemstones includes a Website 2 for maintaining an inventory of portfolios of gemstones for sale 3, and a plurality of identical user terminals 4 connected to the Website 2. Each user terminal 4 includes a gemstone imaging device 6 and a computerized viewing station 7 installed with proprietary client software and a frame grabber for generating a standard portfolio of digital, lifelike color images of a gemstone for sale for inclusion in the Website's inventory. A computerized viewing station 7 or a standard computer terminal 7A can be equally employed for viewing portfolios of gemstones stored in the Website's inventory. A computerized viewing station 7 and a standard computer terminal can be capable of supporting a stereoscopic viewing system for viewing stereoscopic images of a gemstone. represented by a pair of stereoscopic spectacles 8 to be worn by a user, for example. the Simuleyer™ stereoscopic viewing system available from Neotek Inc. Users of the system 1 can be in voice communication with one another either by Voice over IP (VolP), or conventional telephony. With reference now to Figures 2-4, a gemstone imaging device 6 includes a base 9 with an upright member 11 for slidably supporting a CCD camera 12 (constituting a digital image acquisition device) having an optical axis 13. and employed for capturing images of a gemstone 14, the gemstone 14 having a flat table A defining a longitudinal axis T perpendicular thereto. The CCD camera 12 - 12 - is slided along the upright member 11 toward and away from the base 9 (Z-direction) for capturing images of different sued gemstones. The largest table representation diameter of a gemstone which can be imaged by the gemstone imaging device 6 is determined by the CCD camera's field of view when the CCD camera 12 is disposed at the top of the upright member 11, and is approximately 35 mm. An open-ended box-like support block 16 includes a lower portion 17 with a bottom surface 18 and a pair of upright opposite side walls 19A and 19B. the bottom surface 18 being slidably mounted on a pair of two spaced rails 21A and 21B (Y-direction), thereby enabling reciprocation of the lower portion 17 relative to the CCD camera's optical axis 13 through a stroke of about ± 17 millimeters about a centra] position corresponding to the maximum size of a gemstone' s table representation which can be imaged. The bottom surface 18 is formed with a throughgoing aperture 22 disposed above an annular white light source 23 and a light diffuser 24. The light source 23 can be either a 9 Watt fluorescent light source, or can be equally implemented by a series of white LED lights arranged in a circle. The side walls 19A and 19B and are painted white, and are formed with three pairs of opposite grooves 28, 29, and 31 for slidably receiving a gemslone bearing carriage 32. The pairs of grooves are about 1.5 cm, 2.5 cm and 3.5 cm above the base 9, respectively. The lowermost pair of grooves 28 is employed for capturing images of gemstones whose table diameters lie in the range of (9,19) mm. The intermediate pair of grooves 29 is employed for capturing images of gemstones whose table diameters lies in the range of about (2035) mm. The uppermost pair of grooves 31 are employed for capturing images of gemsiones whose table diameters lie in therange of (2..5,9) mm. Each pair of grooves 28. 29 and 31 is provided with a stop (not shown) against which the carriage 32 abuts on its full insertion thereinto. The side walls of the grooves 28. 29 and 31 themselves are non-reflecting. -13- The support block's lower portion 17 is covered by a top surface 33 rigidly attached to the base 9, the top surface 33 being formed with a throughgoing aperture 34 and provided with an annular white fluorescent light source 36 similar to the light source 23. and a light diffuser 37 formed with a throughgoing aperture 38- The apertures 34 and 3S of the top surface 33 and the light diffuser 37. and the annular light source 36 are disposed so as to be co-axial with the CCD camera's optical axis 13 for enabling the capturing of images of a gemstone therethrough. The open-ended box-like support block 16 has the following internal dimensions: length 6±15% cm, width 5±15% cm. and height 4=15% cm. and includes an illumination arrangement 39 constituted by the light sources 26 and 36 together with their respective light diffusers 24 and 37. and the reflective internal surfaces of the side walls 19A and 19B. The support block 16 is adapted, on the one hand, to substantially shield a gemstone from ambient light however without completely excluding light from its interior and: on the other hand, to bathe a gemstone in diffused white light from, opposing orthogonal directions in a balanced manner such that lifelike images of a gemstone can be captured which are neither too brilliant nor too dull. The term "in a balanced manner" should be understood in the sense that the illumination strength from the opposing axial directions is approximately equal within a tolerance of about ±10%. Also, due to the fact that most gemstones are symmetrical about their longitudinal axes, the illumination intensity from the radial direction towards the CCD camera's optical axis is substantially peripherally symmetrical therearound. With reference now to Figures 5A and 5B. the gemstone bearing carriage 32 includes a U-shaped outer frame 41 with a pair of parallel and opposite side support members 42 and 43. and .a cross member 44 extending between side support members" opposite adjacent ends 42A and 43A. The side support members' free adjacent ends 42B and 43B are each formed with a longitudinally extending slit 16 for jxictionaily precluding free uncontrolled movement of the carriage 32 in a pair of grooves 28. 29, and 31. The carriage 32 also includes a pair of parallel and opposite support members 47 which are formed with a pair of grooves 48 for -14- slidably receiving different types of clear, transparent glass slide-like gemstone specimen holders 49A (X-direction). The support members 47 are rotatably mounted on the insides of the -Side support members 42 and 43 between a first position where a gemstone specimen holder 49 is flush with the outer frame 41. and a second position where a gemstone specimen holder 49 subtends an acute angle a upto about 45° relative to the outer frame 41 for capturing of particular still and movable images of a gemstone's surface as described hereinbelow. With, reference now to Figures 6-10, the gemstone specimen holder 49A having opposing first and second major surfaces 51 and 52 is employed for capturing the following images of a gemstone: a still image of its table, a still image of its cullet, a still image of its pavilion, a still image of its girdle, a tillable image of its table, a tillable image of its pavilion, and a pair of complementary- left and right still images of its table for use in displaying a stereoscopic image thereof. The gemstone specimen holder 49A is formed with a throughgoing cylindrical aperture 53 for removably receiving the gemstone's cullet for mounting the gemstone 14 such that its longitudinal axis T is co-directional with the CCD camera's optical axis 13. and its table A is uppermost. When so mounted, the gemstone 14 can be positioned within the CCD camera's field of view such mat its longitudinal axis T is co-axial with the CCD camera's optical axis 13 (see Figure 7A). thereby enabling the capturing of a near full sized screen image of the gemstone's table A (see Figure 7B). Typically. the gemstone is magnified such that" its fills about 90% of the screen's height. In this case, the image of the gemstone's table A is accompanied by the following legend: Size 1.51K, Color K; Clarity VS1. and REMARKS: FLAT STONE, and it include an AOI 54 indicating the location of an imperfection which can be seen in the image. As shown, the image of the gemstone's table A is a floating image in the sense that no visible contour of either the gemstone specimen holder 49 or the cylindrical aperture 53 is discernible therein. In this position, a tiltable image of the gemstone's table A can be captured by the cyclic tilting of the gemstone specimen holder 49A relative to the CCD camera's optical axis 13 indicated by the arrow J. -15- The cylindrical aperture 53 can also be employed for invertedly mounting the gemstone 14 such that its longitudinal axis T is co-directional with the CCD camera's optical axis 13, and its cullet, B is uppermost (see Figure 8A) for enabling the capture of a still image thereof (Figure 8B). On inclination of the gemstone specimen holder 49A relative to the outer frame 41. tile cylindrical aperture 53 can also be employed for mounting the gemstone 14 such that its longitudinal axis T is transversely disposed to the CCD camera's optical axis 13. and its pavilion C is uppermost (see Figure 9A), thereby enabling the capture of a still image thereof (see Figure 9B). In this position, a tiltable image of the gemstone's pavilion C can be captured by the cyclic tilting of the gemstone specimen holder 49A relative to the CCD camera's optical axis 13 indicated by the arrow K. The gemstone specimen holder 49A is also formed with a canoe-shaped aperture 56 whose deepest portion 56A is throughgoing for mounting the gemstone 14 such that its longitudinal axis T is perpendicular to the CCD camera's optical axis 13. and opposite portions of its girdle D are the gemstone's uppermost and lowermost surfaces (see Figure 10A). When so mounted, the gemstone 14 can be positioned within the CCD camera's field of view for enabling die capture of an image of a gemstone's girdle D (see Figure 10B). In this case, the image of the gemstone's girdle D is accompanied by a remark that the girdle is not polished. With reference now to Figures 11A and 11B. a gemstone specimen holder 49B includes a spur gear arrangement 57 with a band rotated gear 58 for driving a driven gear 59 formed with a throughgoing cylindrical aperture 61. The gemstone 14 can be mounted in the gemstone specimen holder 49B with its longitudinal axis T co-axial with the CCD camera's optical axis 13 and its table A uppermost. thereby enabling the capture of a rotatable image thereof. In addition, a precession-like movable image of the gemstone's table can be captured by combining the movements of the gemstone's rotation with a cyclic tilting about the CCD camera's optical axis 13 indicated by the arrow L. With reference now to Figure 12, the genistonc 14 can be invertedly mounted in the cylindrical aperture with its cullet B uppermost such that on -16- inclination of the gemstone specimen holder 49B relative to the outer frame 41. its pavilion C is uppermost thereby enabling the capture of a rotatable image thereof. With reference now to Figures 13-13, a gemstone specimen holder 49C is employed with a light source 62 having a light beam 63 with a light beam axis 64 for imaging a registration marking of light diffusing segments 66 (shown exaggerated in Figure 15) inscribed on the gemstone's table A adjacent one of its borders. The gemstone specimen holder 49C includes a U-shaped member 61 including a lower horizontal leg 68. an upright web 69, and an upper horizontal leg 71. The U-shaped member 67 is so dimensioned that on sliding insertion of the lower leg 68 into the middle pair of grooves 29. the upper leg 71 is disposed above the cover 33. The upper leg 71 is provided with a support 72 with an inclined upper surface 73 with a cylindrical recess 74 for receiving a gemstone receiving insert 76 for mounting the gemstone 14 such that its table A is inclined relative to the CCD camera's optical axis 13 at an included acute angle p. The gemstone receiving insert 76 is rotatable about an axis of rotation R, and is provided with a recess 77 for receiving the gemstone 14 such that the gemstone's longitudinal axis T is coincides with the insert's axis of rotation R. The gemstone specimen holder 49C is set up such that the CCD camera's optical axis 13 views a small footprint 78 of about 1 mm diameter located on the periphery of the gemslone's table A whereupon the CCD camera 12 tracks a lmm wide annular path 79 around the gemstone's table's periphery on rotation of the gemstone receiving insert 76. The light source 62 is set up such that its light beam axis 64 intersects the CCD camera's optical axis 13 at the small footprint 78 whereby the perpendicular 79 to the gemstone's table. A thereat coincides with the bisector 81 of the angle between the CCD camera's optical axis 13 and the light source's light beam axis 64. In this arrangement, the gemstone's table A reflects the light beam 63 to dazzle the CCD camera 12 such that the registration marking 66 is discernible by virtue of its light diffusing segments when disposed at the intersection point of the CCD camera's optical axis 13 and light source's light beam axis 64. -17- With reference now to figure 16. a gemstone specimen holder 49D is similar to the gemstone specimen holder 49C except that its is employed for imaging a a registration marking inscribed onagemstone's glrdle C. In this case, the specimen gemstone holder 49C further includes a spring biased device 82 for urging against the gemstone's table A. With reference now to Figures 17A and 17B, a gemstone specimen holder 49E is provided for imaging silhouettes of the gemstone 14 for the purpose of a computer rendered three dimensional wire frame of the gemstone. and a computer rendered three dimensional representation of the gemstone 14 viewable in three dimensional viewing space. The gemstone specimen holder 49E is provided with a Step motor 83 for rotating a spindle 84 whose axis of rotation 86 is perpendicular to the CCD camera's optical axis 13. The spindle 84 terminates at a spindle end 87 extending into a throughgoing aperture 88, and to which a circular gemstone support member 89 can be replaceably attached. The gemstone support member holder 89 includes a reference marking 91 and is employed together with a light difruser 24A having a black spot 24B tor reasons to be described hereinbelow. The gemstone specimen holder 49E is also provided with a calibration square 92 which lies on a plane 93 perpendicular to the CCD camera's optical axis 13 and co-planar with the axis of rotation 86. The use of the system is now described for the offering for sale of a single new gemstone in the Website and whose portfolio of images is to be displayed on a computerized viewing station and/or a computer terminal which displays visually continuously movable images of a gemstone in the form of a series of computer rendered animated images rather than streaming video images. A seller of the gemstone scrutinizes the gemstone itself, and determines all the necessary information to be conveyed to a potential buyer including the locations of imperfections. The seller enters into ihe Website under a subscriber number, and enters specific details about a gemstone based on his appraisal, the details including inter alia: its dimensions, its cut. color, size in carats, its clarity, its asking price per carat and details of a certificate, if any. -18- The seller selects a suitable gemstone specimen holder and places the gemstone's cullet in the holder's cylindrical aperture whereupon the gemstone is held upright with its table uppermost. The seller slides the gemstone specimen holder into the support block, and adjusts its position such that the center of the gemstone's table is located at the center of the viewing station's screen. The seller adjusts the magnification of the CCD camera such that the image of the gemstone nearly occupies the full screen, and when satisfied with the image, he operates the frame grabber to capture the image under a filename Table Image. The seller can then mark the image with one or more AOIs. for example, as shown in Figure 7B. The seller-repeats the process for capturing near full screen Size still floating images of the gemstone's girdle saved under the filename Girdle Image, the gemstone's pavilion saved under the filename Pavilion Image, and the gemstone's cullet saved under the filename Cullet Image. The seller executes the following steps for obtaining a pair of complementary digital first and last still images of the gemstone's table for use in displaying a visually continuously tillable image thereof, and a visually continuously precession-like movable image thereof: The seller invokes a Tilting Table sub-routine which requires so-called first and last images of a gemstone's table to be saved under the filenames First Image and Last Image, respectively. The seller pivots the gemstone specimen holder through an acute angle a in the range of about 2° to 8° relative to the CCD camera's optical axis in a first sense, and captures the so-called first image of the gemstone's table under the filename First Table Image. The seller then pivots the gemstone specimen holder through the same acute angle in an opposite sense relative to the CCD camera's optical axis: ' and captures the so-called last image of the gemstone's table under the filename Last Table Image. The seller repeats these steps for obtaining a pair of complementary digital first and last still images of the gemstone's pavilion saved under the filenames First Pavilion Image and Last Pavilion Imaee for use in displaying a visually continuously tiltable image thereof. -19- The seller executes the following steps for obtaining a pair of complementary digital left and right images of the gemstone's table for use in displaying a-stereoscopic image tbercof. The-setter invokes a Stereoscopic Image -sub-routine which requires so-called left and right images of a gemstone's table to be saved under the filenames Left Image and Right Image, respectively. The seller repeats the steps described hereinabove for capturing the so-called tillable image of the gemstone's table except that this time the first image of the gemstone's table is saved under the filename Left Image whilst the last image of the gemstone's table is saved under the filename Right Image. In this manner, the two captured images are comparable to the images as seen by a user looking at a stationary object first with one eye only, and then with the other eye only. Alternatively, the right image of the gemstone's table can be captured after the capturing of its left image by a rectilinear displacement of the gemstone specimen holder in the negative X-direction. and then the images are suitably manipulated in X and Y directions by way of a dedicated graphic user interface (GUI) 94 for enabling a clear stereoscopic image to be displayed (see Figure 18). The seller executes the following steps for obtaining a three dimensional wire frame of the gemstone. and a series of images which are required for rendering a three dimensional representation of the gemstone; The seller invokes a Three Dimensional Representation sub-routine which requires tens of bit map silhouettes of the gemstone, and five or more images of the gemstone from different lines of sight and which include all the different facets of the gemstone. The seller mounts the gemstone on the gemstone support member by a so-called "dry adhesion" technique involving pressing the gemstone's table against the gemstone support member with sufficient pressure that the gemstone is naturally adhesively attached to the gemstone support member. The seller then mounts the gemstone support member on the spindle end with the reference marking in the 12 o'clock position, and replaces the base's original light diffuser with the light diffuser having the large black spot for so-called back illumination of the gemstone. The seller then actuates the motor for rotating the gemstone whereupon preferably -20- 90 silhouettes are taken at 4° intervals such that most of the gemstone's vertices are captured in the silhouettes (see Figure 19A). The sub-routine then processes the bit maps-using curve fitting techniques, and the like to determine the locations of all of the gemstone's vertices in three dimensional object space to construct a three dimensional, wire frame 95 of the gemstone from its both detected and calculated vertices (see Figure 19B). The three dimensional wire frame can be manipulated in three dimensional viewing space by means of a suitable control device, i.e., a computer mouse, and also has an indication corresponding to the reference marking. Tlie seller then images the calibration square without altering the set up of the system such that the sub-routine can then calculate the external dimensions of the gemstone. and the relative proportions of its different surfaces. To generate the three dimensional representation of the gemstone, the seller images the gemstone from different lines of sight and then superimposes the three dimensional wire frame such that each of the gemstone's facets is correctly superimposed on its corresponding facets as they appear on the images (see Figure 19B). After each such superimposition, the sub-routine builds up a table of bit map information of textures for each gemstone facet. The potential buyers of gemstones search the inventory of gemstones for sale at the Website in a similar manner as described hereinabove with respect to the already commercially active Websites. However, rather than a potential buyer being presented with a mere list of gemstones which meet his search parameters, in this case, he is presented with a graphic user interface (GUI) 96 showing a nearly full screen size floating lifelike still color image of a gemstone's table of one of the gemstones which met his search parameters which is downloaded from the Website (see Figure 21). In addition, the GUI 96 has a sidebar 97 with relevant details of the gemstone including dimension, cut color, clarity, price, quantity, code. certificate, and seller details. The GUI 96 also has icons for displaying additional images of the gemstone which are also downloaded from the Website as follows: An icon 98 for displaying the still image of its girdle saved under the filename Girdle Image. An icon 99 for -21 - displaying the still image of its cullet saved under the filename Cullet Image. An icon 101 for displaying a still image of its pavilion saved under the filename Pavilion Image. An icon 102 for displaying a stereoscopic image of its table saved under the filenames Left Image and Right Image. An. icon 103 for displaying a visually continuously tiJtable image of its table employing the images saved under the filenames First Table Image and Last Table Image where the image is in the form of a series of computer rendered animated still images l(n) each constructed according to the relationship: I(n) = pI(first) ÷ (1-p) I(Iast) where 0 from a continuously changing line of sight directed toward the gemstone (see Figure 20). An icon 107 for displaying a visually continuously movable rotatable image of its pavilion by manipulating the image saved under the filename Pavilion Image in a similar manner for displaying a visually continuously rotatable image of its table. An icon 108 for displaying a visually continuously precession-like movable image I(z) of its table in accordance with a continuously changing line of sight directed toward the gemstone by manipulating the images I(first) and I(last) as foliows I(z) = pI[rot(flrst)] ÷ (l-p)I[rot(last)] where 0 -22- image and a last direction during the capture of the last image such that the two directions define a pJane therebetween and intersect at an acute angle a; and An icon 109 for displaying zoom images of one or more of the gemstone's imperfections as shown by Areas of Interest introduced by die gemstone's seller on one or more of the still images of its table, girdle, cullet. and pavilion. An icon 111 for displaying a three dimensional representation of the gemstone viewable in three dimensional viewing space where each of the" representation's facets is textured in accordance with a particular line of sight directed toward the gemstone in accordance with the relationship: F(i)=Sp(j)F(ij) where Sp(j)2=l for j=l to n different textures of the same facet F(i) each taken from, a different line of sight, and p(j) are directional cosines of the line of sight in a predefined Cartesian coordinate system. Finally, the GUI can also include an icon 112 for displaying a Gem Certificate 113 (see Figure 22) of the gemstone issued by an internationally recognized body, the Gem Certificate including an Issue Number, date of issue, details regarding shape, cut. weight, proportions/measurement, clarity, fluorescence, color and comments. In addition, the Gem Certificate 113 includes one or more of the lifelike color images of the gemstone's major surfaces, i.e. its table, girdle, cullet and pavilion, together with AOIs 114 delimiting boundaries around its imperfections, Alternatively, the images can be replaced by wire frame representations of the gemstone whilst the AOIs can be replaced by arrows 116. and the like for graphically indicating the location of an imperfection. On the basis of a gemstone's portfolio of digital lifelike, color images, together with its Gem Certificate if available, a trained professional has all the necessary information to substantiate the details provided by the seller in respect of a gemstone that he is contemplating to purchase, and also evaluate it? market worth without having to physically scrutinize the gemstone itself. -23- While tlie invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention can be made within the scope of the appended Claims. For example, the digital acquisition device can be provided with zooming capabilities for magnifying a gemstone whilst a Gem Certificate for a particular gemstone can be distributed in hard copy to potential buyers in a conventional manner. In additioa. the method for displaying a visually continuously movable image at a computer terminal can be equally applied to any object, as can the method for obtaining a pair of complementary digital left and right images of an object for displaying a stereoscopic image thereof. 24 WE CLAIM: 1. A system for trading in gemstones, each gemstone having a flat table defining a longitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet, the system comprising a plurality of user terminals for capturing digital lifelike color images of a gemstone, each user terminal capable of generating the same standard portfolio of digital lifelike color images of a particular gemstone for enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards. 2. A system according to Claim 1 wherein a gemstone's portfolio includes at least one element of the group consisting of: a floating still image of its table; a floating still image of its pavilion; 25 a floating still image of its girdle; a floating still image of its cullet; a pair of complementary left and right still images of a gemstone's surface for enabling the display of a stereoscopic image thereof; a movable image of one or gemstones surfaces; a three dimensional representation of a gemstone viewable in three dimensional viewing space; an image of its registration marking; details of the sizes and relative proportions of a gemstone's surface; 26 a Gem Certificate. 3. A system according to Claim 1 wherein at least one image includes : an Area of Interest indicating the presence of an imperfection discernible therein, and/or a color chart. 4. A system according to Claim 2 wherein said movable image is : 27 - a tiltablc image where each computer rendered animated still image I(n) is constructed according to the relationship I(n) = where 0 - a rotatable image where each computer rendered animated image I(rot) is constructed according to the relationship: I(rot) where pixel coordinates or - a precession-like movable image where each computer rendered animated image I(z) is constructed according to the relationship: I(z) - pI[rot(first)] - ' (Ip)I[rot(last)] where 0 of the gemstone's surface with the gemstone's longitudinal axis defining a first direction during the capture of the first image and a last direction during the capture of ihe last image such that the two directions define a plane therebetween and intersect at an acute angle a, and l(rot) where pixel coordinates (/. j) 5. A system according to Claim 2. wherein said three dimensional representation has facets each textured in accordance with a particular line of sight directed toward the gemstone in accordance with the relationship: F(i)=S(j)F(ij) where Sp(j)2=1 for j=1 to n different textures of the same facet F(i) each taken from a different line of sight, and where p(j) are directional cosines of the line of sight in a predefined Cartesian coordinate system. 6. A system according to Claim 2. wherein said Gem Certificate comprises at least one representation of die gemstone in which an imperfection of the gemstone -28-is discernible, and whose location on at least one of said at least one representation is graphically indicated thereon. 7. A system according to Claim l,option coinprising at least one data storage device for storing said portfolios of digital lifelike color images. 8. A data storage device storing a plurality of portfolios of digital. lifelike, color images of gemstones for sale for use in the system of trading in Hemstones according to any one of Claims 1 to 7. A method of tradins in eemstones based on the system of any one of Claims 1 to 7 and on the data storage device of Claim 8. enabling one or more potential buyers of gemstones to remotely access the data storage device whereupon each potential buyer can peruse through the portfolio of images of a gemstone which he is contemplating to purchase.' . 10. A user terminal for capturing images of a gemslone. "the user terminal comprising: a) a base; b) a support block mounted on said base, 'and supporting a light-transmissive gemstone bearing member holding a gemstone in a central portion of said support block, said support block substantially shielding the gemstone from ambient light without completely excluding ambient light from said central portion and including an illumination arrangement for illuminating the gemstone from opposing orthogonal directions in a substantially balanced manner, said directions including a first axial direction for illuminating a first major surface of said gemstone bearing member, a second axial direction for illuminating a second major surface of said gemstone bearing member opposite to said first major surface, and a third direction for radially illuminating said central portion; and -29- a digital image acquisition device with an optical axis, and being mounted on said base for capturing an image of the illuminated gemstone through an aperture formed in said support block facing said first major surface of said gemstone bearing member. 11. A user terminal according to Claim 10. wherein said support block has an open-ended box-like shape with a top surface, a bottom surface and a pair of opposing substantially parallel walls. 12. A user terminal according to either Claim 10 11, wherein said support block has the following internal dimensions: length 6±15% cm. width 5±15% cm. and height 5±15% cm. 13. A user terminal according to any one of Claims 10 to 12, wherein said illumination arrangement includes at least one annular diffused whito light source for illuminating in at least one of said first and second axial directions. 14. A user terminal according to any one of Claims 10 to 13, wherein said illumination arrangement includes light reflective portions for reflecting light radially towards said central portion. 15. A user terminal according to any one of Claims 10 to 14, wherein said gemstone bearing member includes a carriage with an outer frame for being slidably received in a pair of opposite grooves, and a pair of support members pivotably mounted on said outer frame for assuming a first position substantially flush with said outer frame and a second position subtending an acute angle relative to said outer frame. 16. A user terminal according to Claim 15, wherein said outer frame includes a pair of opposite support members, at least one of said support members having a longitudinally extending slit for frictionally precluding free uncontrolled movement of said carriage in a pair of grooves. 30 17. A user terminal according to any one of Claims 10 to 15. wherein said gemstone bearing member comprises a flat, light-transmissive, glass slide-like gemstone specimen holder with at least one throughgomg aperture for removably receiving a portion of a gemstone's body for mounting the gemstone in a predetermined position. 18. A user terminal according lo Claim 17, wherein said aperture has the shape of a cylinder or the shape of a canoe. 19. A user terminal accordins to any one of Claims 10 to 18, wherein said gemstone bearing member comprises a flat, light-transmissive, glass slide-like gemstone specimen holder with a rotatably mounted member for supporting a gemstone. which may include a gear spur arrangement for rotating said rotatably mounted member. 20. A user terminal according to any one of Claims 10 to 14, further comprising a gemstone specimen holder with a rotatable gemstone specimen holder for rotating a gemstone with its girdle facing said digital image acquisition device. 21. A user terminal according to.Claim 20: wherein said gemstone specimen holder includes a calibration square lying in a plane perpendicular to said optical axis and co-planar with an axis of rotation of said rotatable gemstone specimen holder. 22. A user terminal according to either Claim 20 or 21. wherein said gemstone specimen holder is replaceable. 23. A user terminal according to any one of Claims 10 to 14, further comprising: (d) a light source having a light beam with a light beam axis intersecting said optical axis at an intersection point, and defining a bisector therebetween; and -31- (e) a gemstone supporting member for supporting a gemstone such that said bisector coincides with the perpendicular of the portion of its surface; and being selectively displaceable relative to said intersection point whereby the gemstone's surface is capable of being scanned along a predetermined scanning path for enabling the detection of the location of a gemstone's registration marking. 24. A user terminal according to Claim 23. wherein said gemstone supporting member is slidingly supported in said support block. 25. A user terminal according to either one of Claims 23 or 24, wherein said gemstone supporting member includes a rotatably mounted gemstone receiving insert for mounting the gemstone. 26. A user terminal according to Claim 25, wherein said gemstone receiving insert is replaceable. 27. A user terminal according to any one of Claims 23 to 26, further comprising an urging member for securing a gemstone in said gemslone support member. 28. A gemstone examination device for enabling the detection of the location of a gemstone's registration marking, the registration marking including a series of light diffusing segments located on a flat polished surface of the gemstone defining a longitudinal axis perpendicular thereto, the gemstone examination device comprising: (a) a light source having a light beam with a light beam axis; (b) a magnifying optical device having an optical axis intersecting said light beam axis at an intersection point, and defining a bisector therebetween; and (c) a gemstone supporting member for supporting a gemstone such that said bisector coincides with the perpendicular of the portion of the gemstone's surface located at said intersection point, and being 32 selectively displaceable relative to said intersection point whereby the gemstone's surface is capable of being scanned along a predetermined scanning path. 29. A gemstone examination device according to Claim 28. wherein said gemstone supporting member includes a rotatably mounted gemstone receiving insert for mounting the gemstone. 30. A gemstone examination device according to either Claim 28 or 29, wherein said gemstone receiving insert is replaceable. 31. A gemstone examination device according to any one of Claims 28 to 30. further comprising an urging member for securing a gemstone in said gemstone support member. 32. A gem certificate for a gemstone. the gem certificate comprising at least one representation of the gemstone in which an imperfection of the gemstone is discernible, and whose location on at least one of said at least one representation is graphically indicated thereon. 33. A sem certificate according to Claim 32, wherein said at least one representation includes at least one element from the group consisting of: a digital lifelike color image of the gemstone; a wire frame representation of the gemstone; an Area of Interest delimiting a boundary around an imperfection. 34. A method for displaying a visually continuously movable image of a gemstone's surface at a computer terminal remote from a database, the method comprising the steps of: (a) downloading bit map information regarding a gemstone from the database to the computer terminal; 33 (b) generating from the bit map information at the computer terminal an on-the-fly computer rendered animated still image of the gemstone from a particular line of sight directed toward the gemstone; and (c) refreshing the computer rendered animated still image of the gemstone from different lines of sight directed toward the gemstones as indicated by a potential buyer of the gemstone at his computer terminal thereby displaying a series of computer generated animated still images of the gemstone perceived as a visibly continuously movable image by the potential buyer. 35. A method for displaying a movable image of a gemstone's surface according to Claim 34. wherein said movable image is: - a tillable image where each computer rendered animated still image I(n) is constructed according to the relationship I(n) = pI(firsl) ÷ (1-p) I(Iast) where 0 surface with the eemstone's longitudinal axis defining a first direction during the capture of the first image and a last direction during the capture of the last image such that the two directions define a plane therebetween and intersect at an acute angle a; or - a rotatable image where each computer rendered animated image I(rot) is constructed according to the relationship; - a precession-like movable image where each computer rendered animated image l(z) is constructed according to the relationship: I(z) = pI[rot(first)] ÷ (l-p)I[rot(Iast)] where 0 of the gemstone's surface with the gemstone's longitudinal axis defining a first direction during the capture of the first image and a last direction during the capture of the last image such that the two directions define a plane therebetween and intersect at an acute angle a. and -34- I {rot) where pixel coordinates - a visually continuous movable image of a three dimensional representation of a gemstone viewable in three dimensional viewing space where each of the representation's facets is textured in accordance with a particular line of sight directed toward the gemstone in accordance with the relationship: F(i)=Sp(j)F(ij) where Sp(j)2=l for j=l to n different textures of the same facet F(i) each taken from a different line of sight, and p(j) are directional cosines of the line of sight in a predefined Cartesian coordinate system. 36. A method for obtaining af a streoscopic image of a gemstone"s table, the method comprising the steps of: (a) mounting the gemstone in the field of view of a digital image acquisition device; (b) acquiring a left image of the gemstone; (c) .displacing the gemstone specimen holder relative to the image acquisition device's field of view; and (d) acquiring a right image of the gemstone. 37. A method according to Claim 36. wherein step (c) includes: - translating the gemstone by a distance substantially corresponding to the separation between the eyepieces of a binocular microscope, or - translating and rotating the gemstone so that the gemstone's longitudinal axis defines two intersecting directions in the axis' extreme positions. A system for trading in gemstones, which is having a flat table defining a longitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet The system comprises a plurality of user terminals for capturing digital lifelike color images of a gemstone, each user terminal capable of generating the same standard portfolio of digital lifelike color images of a particular gemstone for enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards.

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FIELD OF THE INVENTION
This invention relates to a system and method for trading in precious gemstones. gemstone examination apparatus for examination of gemsiones. a method for obtaining a pair of complementary digital left and right images of an object for displaying a stereoscopic image thereof, and a method for displaying a visually continuously movable image of an object at a computer terminal.
BACKGROUND OF THE INVENTION
Trade in precious gemstones in general - and diamonds in particular (hereinafter referred to gemstones) is based on evaluations by trained professionals who carefully scrutinize a aernstone with their naked eve and/or usins a X10 magnifying glass, or a microscope. A professional evaluation of a gemstone depends on quantifiable parameters such as weight, color, clarity in terms of its imperfections, polish, cut and relative proportions of a gemstone's different portions, and also on its inherent beauty in terms of its brilliance in the way that it reflects light. A gemstone's proportions can be calculated from a three dimensional wire frame representation of a gemstone. for example, as implemented in calibrated optic digital image acquisition systems commercially available from Ogi Ltd. Israel; Sarin Ltd. Israel; and others. Certification of a gemstone can be obtained from one or more internationally recognized bodies, for example. The Gem Trade Laboratory of the Gemological Institute of America. Other certification can be in the form of a Gem Certificate as illustrated and described in US Patent 5.899.503
Gemstones are now traded over the Internet at various Websites including inter alia vvwvv.gemkey.net, www.diamond.net. and www.poJyaon.com. The Websites act as virtual market places, and maintain inventories of gemstones for

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sale including details of the above-mentioned parameters for each gemstone together with its asking price per carat. In addition, gemstones with similar specifications can be put up for sale in clusters, A potential, buyer of a gemstone can search an inventory of gemstones for sale by specifying search parameters, for example, carat, asking price per carat, and the like. Assuming that the inventory lists one or more gemstones, or clusters of gemstones, meeting his search criteria. the buyer is presented with same. The buyer then enters a purchasing order in respect of one or more of the items in which he is interested in which are then sent to him for evaluation, and which are returned to the seller if the buver cannot reach an agreement with him. Thus, whilst trade in gemstones has been somewhat streamlined, there still remains a considerable undesirable movement of stock which could otherwise be avoided if a potential buyer of a gemstone, or a cluster of gemstones. could remotely and independently substantiate a seller's evaluation of a gemstone and in particular its market value.
Registration markings are now inscribed on gemstones for identification purposes. The most common type of registration marking includes letters and numbers constituted by a series of spaced apart light diffusing segments on one of a gemstcne's flat, polished surfaces, find typically either its table or its girdle. This type of marking uses a 0.5 ?n high segments and is about 50um long so as to be invisible to the naked eye. thereby not detracting from a gemstone's beauty. Detection of a gemstone's registration marking requires at least a X200 magnification and scanning either a gemstone's entire table or girdle, and is a time consuming and cumbersome process.
SUMMARY OF THE INVENTION
Trade in gemstones involves transactions between "a seller of a gemstone " and "a potential bin-er of a gemstone". however, a seller in one transaction may be a potential buyer in another transaction by virtue of the nature of trade in gemsiones. Therefore, the present specification employs the specific terms "o
seller of a gemstone" and "a potential buyer of a gemstone". and sometimes the

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generic term " a user" as most appropriate within the context of the description. Moreover, the present specification pertains to trade in single gemstones only, however, it should be understood that the present invention equally applies to trade in clusters of similar gemstones. Also, the present specification pertains to trade in so-called circular cut gemstones, however, it should be understood that the present invention also equally applies to trade in other shaped gemstones.
In accordance with a fust aspect of the present invention, there is provided a system for trading in gemstones. each gemstone having a flat table defining a Ipngitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet, the system comprising a plurality" of user terminals for capturing digital lifelike color images of a gemstone. each of said user terminals being capable of generating the same standard portfolio of digital lifelike color images for a particular gemstone, thereby enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards.
In accordance with a second aspect of the present invention, there is provided a method of trading in gemstones. the method comprising the steps:
(a) .providing a data storage device with a plurality of portfolios of digital lifelike color images of gemstones each enabling a potential buyer of a gemstone to independently evaluate its market value from its associated portfolio of images in accordance with internationally recognized standards; and
(b) enabling one or more potential buyers of gemstones remote access to the data storage device whereupon a potential buyer of a gemstone can peruse through the portfolio of images of a particular gemstone which he is contemplating to purchase.
A system and method for trading in precious gemstones in accordance with the present invention necessarily includes the generating of a standard portfolio of digital, lifelike color images for a particular gemstone whereby a potential buyer of a precious gemstone can independently, on the one hand, determine iis trade recognized quantifiable parameters and. on the other hand, appreciate its beauty for

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evaluating its market value as if he was physically scrutinizing the gemstone itself. The necessity that each and every user terminal of the system will generate substantially identical portfolios for the same gemstone isxrucial to the trading of gemstones since otherwise potential buyers will not be able to implicitly rely on a portfolio when contemplating whether he wants to purchase a particular gemstone. The system and method of the present invention can either be implemented on a server based intranet or on a business-to-business Website maintaining an inventory of portfolios of images of gemstones for sale. In both implementations, a potential buyer can preferably conduct a telephone conversation with a seller of a gemstone to instruct him to show him on-line particular views of a gemstone that he is interested in purchasing.
The imaging of a gemstone is particularly difficult due to its highly polished surfaces reflecting light in such a manner that its interior is obscured for example, as in photographs for advertising purposes which accentuate a gemstone's beauty but do not reveal its imperfections. Against this, photographs of a gemstone's imperfections are normally "lifeless " in the sense that they are devoid of any of the gemstone's beauty, for example, as obtainable by apparatus for examining gemstones illustrated and described in US Patent 4.906,083 to Sattler which employs dark field illumination or polarized filters. The present invention overcomes the difficulties of imaging a gemstone by on the one hand, effectively shielding a gemstone from ambient light which would otherwise cause two user terminals to generate two different portfolios of images depending on their local environments and; on the other hand, so-called "bathing" a gemstone in diffused artificial white light in such a balanced manner such, that captured images arc neither too brilliant nor too lifeless. Moreover, at least some of the images are so-calLed "'floating' images of uniform background and illumination, and which do not include discernible -contours of a transparent gemstone specimen holder employed for mounting a gemstone during the capturing of images thereof.
A gemstone's portfolio of digital. lifelike, color images includes one or more still images of its table, its girdle, and the like, and also preferably includes

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one or more movable images of a gemstone's surface, images suitable for displaying a stereoscopic image of a gemstone using any one of a number of commercially, available systems, for example, the Simuleyer™ stereoscopic viewing system available from Neotek Inc.. a three dimensional representation of a gemstone viewable in three dimensional viewing space in a manner similar to that described in US Patent 5.793.372. an image of a gemstone's registration marking, and a Gem Certificate including at least one representation of a gemstone with its imperfections indicated for the purpose of evaluation by a potential buyer. The movable images may include one or more of the following images: First, a so-called tillable image of a gemstone's surface which may be either its table, its girdle orjtsjpavilion. Second, a rotatable image of a gemstone's surface which may be either its table or its pavilion. And lastly, a precession-like movable image of a geinstonc's table as the gemstone undergoes a superimposed combination of the movements .for the so-called tillable image of its table together with die semstone's rotation about its longitudinal axis. The movable images may be true video streams, or series of computer rendered animated images generated on-the-fly at a potential buyer's computer terminal from bit map information downloaded thereat. The movable images of a gemstone are important supplements to the still images sirice they can better provide a sense of the location and the depth of an imperfection in a gemstone. and furthermore they can reveal imperfections which may otherwise be concealed behind a gemstone's surface blindingly reflecting light. The images can also be manually processed by a seller to include Areas of Interest (AOls) graphically indicating the locations of a gemstone's imperfections for facilitating a potential buyer's awareness of same, and therefore improving the accuracy of his evaluation of the gemstone's market value. The images of a gemstone, and especially those which include AOls, can be readily incorporated in a Gem Certificate issued by an internationally recognized body, for example, the above mentioned Gem Trade Laboratory. Also, one or more of the images may include a color chart for facilitating a potential buyer's determination of a gemstone's color.

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In accordance with a still yet another aspect of the present invention, there is provided a method for displaying a visually continuously movable image of a gemstone at a computer terminal remote from a database, the method comprising the steps of:
(a)downloading bit map information regarding a gemstone from the
database to the computer terminal;
(b)generating from the downloaded bit map information at the computer teiminal an on-the-fly computer rendered animated image of the gemstone from a particular line of sight directed toward the gemstone: and
(c)refreshing the computer rendered animated image of the gemstone from different lines of sight directed toward the gemstones as indicated by a potential buyer of the gemstone at his computer terminal thereby displaying a series of animated images of the gemstone perceived as a visually continuously movable image by the potential buyer. The method for displaying a visually continuously movable image of a gemstone according to the present invention at a potential buyer's computer terminal overcomes latency and bandwidth problems involved in transmitting video streams, for example, over the Internet. The visually continuously movable image can be of a particular surface of a gemstone, for example, its table, or alternatively. it can be of a three dimensional representation of a gemstone. The visually continuously movable image of a gemstone's table can be a tillable image, a rotatable image, or a precession-like movable image.
In the case of a tillable image of a gemstone's surface, each computer rendered animated image I(n) displayed on a potential buyer's computer terminal is constructed in accordance with the relationship I(n) = pI(first) + (1-p) I(last) where 0
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the last still image such that the two directions define a plane therebetween and intersect at an acute angle a-
In the case of a rotatable image of a gemstone's surface, each computer rendered animated image I(rot) displayed on a potential buyer's computer terminal is constructed m accordance with the relationship;
I(rot) where pixel coordinates
In the case of a visually continuously precession-like movable image of a gemstone's surface, each computer rendered animated image I(z) displayed on a potential buyer's computer terminal is constructed in accordance with the relationship I(z) = pI[rot(fwst)] + (l-p)I[rot(last)] where 0 I(rot) where pixel coordiates
In the case of a three dimensional representation of a gemstone viewable in three dimensional viewing space, each computer generated animated image displayed on a potential buyer's computer terminal is constructed by displaying a wire frame representation of the gemstone on the computer terminal in accordance with a particular line of sight directed toward the gemstone, and then separately texturing each of the representation's facets in accordance with the relationship: F(i)=Sp(j)F(ij) where Sp(j)2=l for j=l to n different textures of the same facet F(i) each taken from a different line of sight in accordance with a particular line of sight directed toward the gemstone, and p(j) are directional cosines of the line of sight in a predefined Cartesian coordinate system.
In accordance with a still yet another aspect of the present invention, there is provided a method for obtaining a pair of complementary digital left and right s::Il

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images of a gemstone for use in displaying a stereoscopic image thereof, the method comprising the steps of:
(a) mounting a gemstone in the field of view of a digital image
acquisition device;
(b) acquiring a left image of the gemstone;
(c) displacing the gemstone in the image acquisition device's field of
view; and
(d) acquiring a right image of the gemstone.
A binocular microscope, for example, as illustrated and described in aforementioned US Patent 4,906.083 enables a user to naturally perceive a stereoscopic image of a gemstone. In a similar manner, a pair of image acquisition devices can be employed for acquiring epipolar left and right still images of a gemstone, such images being essential so as to preclude a blurred stereoscopic image. The method of obtaining a pair of complementary left and right images of the present invention precludes the need for a pair of digital image acquisition devices and can be readily effected using the gemstone imaging device of the present invention. The displacement of the gemstone within the image acquisition device's field of view may be either a translation by a distance substantially equal to the separation of the eyepieces of a binocular microscope, or the gemstone can be both translated and rotated between two extreme positions equidistanced with respect to the image acquisition device's optical axis, in which positions the gemstone's longitudinal axis defines two directions which define a plane and intersect at an acute angle a.
BRIEF DESCRIPTION OF THE DRAWINGS
In order 10 understand the invention and lo see how it may be carried out in practice, preferred embodiments will now be described, by way of non-limiting examples onh. with reference to the accompanying drawings, in which similar pans are likewise numbered and in which:

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Fig. 1 is a pictorial representation showing an Internet based system for trade in precious gemslones in accordance with the present invention:
Fig. 2 is a pictorial representation showing a user terminal of the system of Figure 1 including a gemstone imaging device and a computerized viewing station:
Fig. 3 is a pictoria] exploded representation showing .the gemstone imaging device of Figure 2:
Fig. 4 is a pictorial transverse cross section representation showing the gemstone imaging device of Figure 2 along line IV-IV therein;
Figs. 5A and 5B are pictorial representations showing two positions of a gemstone bearing carriage holding a first type of a gemstone specimen holder:
Fig. 6 is a pictorial longitudinal cross section representation of the first type of gemstone specimen holder along line VI-VI in Figure 5A;
Fig. 7 A is a pictorial representation showing the first type of gemsione specimen holder mounting a gemstone with its table uppermost;
Fig. 7B is a pictorial representation showing a near full screen size floating image of the gemstone's table as captured by the user terminal when the gemstone is mounted as shown in Figure 7A;
Fig. 8A is a pictorial representation showing the first type of gemstone specimen holder mounting a gemstone with its cullet uppermost;
Fig. 8B is a pictorial representation showing a near full screen size floating image of the gemstone's cullet as captured by the user terminal when the gemstone is mounted as shown in Figure 8A:
Fig. 9A is a pictorial representation showing the first type of gemstone specimen holder mounting a gemstone with its pavilion uppermost;
Fig. 9B is a pictorial representation showing a near full screen size floating image of the gemstone's pavilion as captured by the user terminal when the gemstone is mounted as shown in Figure 9A;
Fig. 10A is a pictorial side representation showing the first type of gemstone specimen holder rnouming a gemstone with opposite portions of its girdle being uppermost and lowermost;

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Fig. 10B is a pictorial representation showing a near full screen size floating image of the gemstone's girdle as captured by the user terminal when the gemstone is mounted as shown in Figure 10A;
Figs. 11A and 1 1.B are pictorial representations showing a second type of a gemstone specimen holder for enabling the capturing of a rotatable image of a gemstone's table;
Fig. 12 is a pictorial representation showing of the second type of gemstone specimen holder for enabling the capturing of a rotatable image of a gemstone's pavilion;
Fig. 13 is a pictorial representation showing a third type of gemstone specimen holder for enabling the capturing of an image of a gemstone's registration marking inscribed on its table;
FIH. 14 ia a pictrial representation chowing a close-up view of the, illumination of the gemstone's table, and its imaging:
Fig. 15 is a pictorial representation showing the scanning of the gemstone's surface for locating the registration marking inscribed thereon;
Fig. 16 is a pictorial representation showing a fourth type of gemstone specimen holder for enabling the capturing of an image of a gemstone's registration marking inscribed on its girdle;
Fig. 17A is a pictorial representation showing a fifth type of gemstone specimen holder for enabling the capturing of images for generating a three dimensional wire frame representation of a gemstone:
Fig. 17B is a top view of the gemstone specimen holder of Figure 17A:
Fig. 18 is a pictorial representation showing a graphic user interface for the preparation of a pair of complementary left and right still images of a gemstone's table for generating a stereoscopic image thereof for display on a computerized viewing station of the system of Figure 1;
Fig. 19A is a top view a back illuminated silhouette of a gemstone;
Fig. 19B is a pictorial representation of a three dimensional wire frame being superimposed onto an image of a gemstone:

- 1 1 ~
Fig. 20 is a schematic representation showing the rotational transformation of an image for rendering visually continuously rotatable and precession-like images of a gemstone;
Fig. 21 is a pictorial representation showing a graphic user interface of a gemstone's portfolio of digital, lifelike, color images as viewed by a potential buyer; and
Fig. 22 is a pictorial representation showing a Gem Certificate of a gemstone.
DETAILED DESCRIPTION OF THE DRAWINGS
With reference to Figure 1, an Internet based system 1 for trade in precious gemstones includes a Website 2 for maintaining an inventory of portfolios of gemstones for sale 3, and a plurality of identical user terminals 4 connected to the Website 2. Each user terminal 4 includes a gemstone imaging device 6 and a computerized viewing station 7 installed with proprietary client software and a frame grabber for generating a standard portfolio of digital, lifelike color images of a gemstone for sale for inclusion in the Website's inventory. A computerized viewing station 7 or a standard computer terminal 7A can be equally employed for viewing portfolios of gemstones stored in the Website's inventory. A computerized viewing station 7 and a standard computer terminal can be capable of supporting a stereoscopic viewing system for viewing stereoscopic images of a gemstone. represented by a pair of stereoscopic spectacles 8 to be worn by a user, for example. the Simuleyer™ stereoscopic viewing system available from Neotek Inc. Users of the system 1 can be in voice communication with one another either by Voice over IP (VolP), or conventional telephony.
With reference now to Figures 2-4, a gemstone imaging device 6 includes a base 9 with an upright member 11 for slidably supporting a CCD camera 12 (constituting a digital image acquisition device) having an optical axis 13. and employed for capturing images of a gemstone 14, the gemstone 14 having a flat table A defining a longitudinal axis T perpendicular thereto. The CCD camera 12

- 12 -
is slided along the upright member 11 toward and away from the base 9 (Z-direction) for capturing images of different sued gemstones. The largest table representation diameter of a gemstone which can be imaged by the gemstone imaging device 6 is determined by the CCD camera's field of view when the CCD camera 12 is disposed at the top of the upright member 11, and is approximately 35 mm.
An open-ended box-like support block 16 includes a lower portion 17 with a bottom surface 18 and a pair of upright opposite side walls 19A and 19B. the bottom surface 18 being slidably mounted on a pair of two spaced rails 21A and 21B (Y-direction), thereby enabling reciprocation of the lower portion 17 relative to the CCD camera's optical axis 13 through a stroke of about ± 17 millimeters about a centra] position corresponding to the maximum size of a gemstone' s table representation which can be imaged. The bottom surface 18 is formed with a throughgoing aperture 22 disposed above an annular white light source 23 and a light diffuser 24. The light source 23 can be either a 9 Watt fluorescent light source, or can be equally implemented by a series of white LED lights arranged in a circle.
The side walls 19A and 19B and are painted white, and are formed with three pairs of opposite grooves 28, 29, and 31 for slidably receiving a gemslone bearing carriage 32. The pairs of grooves are about 1.5 cm, 2.5 cm and 3.5 cm above the base 9, respectively. The lowermost pair of grooves 28 is employed for capturing images of gemstones whose table diameters lie in the range of (9,19) mm. The intermediate pair of grooves 29 is employed for capturing images of gemstones whose table diameters lies in the range of about (2035) mm. The uppermost pair of grooves 31 are employed for capturing images of gemsiones whose table diameters lie in therange of (2..5,9) mm. Each pair of grooves 28. 29 and 31 is provided with a stop (not shown) against which the carriage 32 abuts on its full insertion thereinto. The side walls of the grooves 28. 29 and 31 themselves are non-reflecting.

-13-
The support block's lower portion 17 is covered by a top surface 33 rigidly attached to the base 9, the top surface 33 being formed with a throughgoing aperture 34 and provided with an annular white fluorescent light source 36 similar to the light source 23. and a light diffuser 37 formed with a throughgoing aperture 38- The apertures 34 and 3S of the top surface 33 and the light diffuser 37. and the annular light source 36 are disposed so as to be co-axial with the CCD camera's optical axis 13 for enabling the capturing of images of a gemstone therethrough.
The open-ended box-like support block 16 has the following internal dimensions: length 6±15% cm, width 5±15% cm. and height 4=15% cm. and includes an illumination arrangement 39 constituted by the light sources 26 and 36 together with their respective light diffusers 24 and 37. and the reflective internal surfaces of the side walls 19A and 19B. The support block 16 is adapted, on the one hand, to substantially shield a gemstone from ambient light however without completely excluding light from its interior and: on the other hand, to bathe a gemstone in diffused white light from, opposing orthogonal directions in a balanced manner such that lifelike images of a gemstone can be captured which are neither too brilliant nor too dull. The term "in a balanced manner" should be understood in the sense that the illumination strength from the opposing axial directions is approximately equal within a tolerance of about ±10%. Also, due to the fact that most gemstones are symmetrical about their longitudinal axes, the illumination intensity from the radial direction towards the CCD camera's optical axis is substantially peripherally symmetrical therearound.
With reference now to Figures 5A and 5B. the gemstone bearing carriage 32 includes a U-shaped outer frame 41 with a pair of parallel and opposite side support members 42 and 43. and .a cross member 44 extending between side support members" opposite adjacent ends 42A and 43A. The side support members' free adjacent ends 42B and 43B are each formed with a longitudinally extending slit 16 for jxictionaily precluding free uncontrolled movement of the carriage 32 in a pair of grooves 28. 29, and 31. The carriage 32 also includes a pair of parallel and opposite support members 47 which are formed with a pair of grooves 48 for

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slidably receiving different types of clear, transparent glass slide-like gemstone specimen holders 49A (X-direction). The support members 47 are rotatably mounted on the insides of the -Side support members 42 and 43 between a first position where a gemstone specimen holder 49 is flush with the outer frame 41. and a second position where a gemstone specimen holder 49 subtends an acute angle a upto about 45° relative to the outer frame 41 for capturing of particular still and movable images of a gemstone's surface as described hereinbelow.
With, reference now to Figures 6-10, the gemstone specimen holder 49A having opposing first and second major surfaces 51 and 52 is employed for capturing the following images of a gemstone: a still image of its table, a still image of its cullet, a still image of its pavilion, a still image of its girdle, a tillable image of its table, a tillable image of its pavilion, and a pair of complementary- left and right still images of its table for use in displaying a stereoscopic image thereof.
The gemstone specimen holder 49A is formed with a throughgoing cylindrical aperture 53 for removably receiving the gemstone's cullet for mounting the gemstone 14 such that its longitudinal axis T is co-directional with the CCD camera's optical axis 13. and its table A is uppermost. When so mounted, the gemstone 14 can be positioned within the CCD camera's field of view such mat its longitudinal axis T is co-axial with the CCD camera's optical axis 13 (see Figure 7A). thereby enabling the capturing of a near full sized screen image of the gemstone's table A (see Figure 7B). Typically. the gemstone is magnified such that" its fills about 90% of the screen's height. In this case, the image of the gemstone's table A is accompanied by the following legend: Size 1.51K, Color K; Clarity VS1. and REMARKS: FLAT STONE, and it include an AOI 54 indicating the location of an imperfection which can be seen in the image. As shown, the image of the gemstone's table A is a floating image in the sense that no visible contour of either the gemstone specimen holder 49 or the cylindrical aperture 53 is discernible therein. In this position, a tiltable image of the gemstone's table A can be captured by the cyclic tilting of the gemstone specimen holder 49A relative to the CCD camera's optical axis 13 indicated by the arrow J.

-15-
The cylindrical aperture 53 can also be employed for invertedly mounting the gemstone 14 such that its longitudinal axis T is co-directional with the CCD camera's optical axis 13, and its cullet, B is uppermost (see Figure 8A) for enabling the capture of a still image thereof (Figure 8B). On inclination of the gemstone specimen holder 49A relative to the outer frame 41. tile cylindrical aperture 53 can also be employed for mounting the gemstone 14 such that its longitudinal axis T is transversely disposed to the CCD camera's optical axis 13. and its pavilion C is uppermost (see Figure 9A), thereby enabling the capture of a still image thereof (see Figure 9B). In this position, a tiltable image of the gemstone's pavilion C can be captured by the cyclic tilting of the gemstone specimen holder 49A relative to the CCD camera's optical axis 13 indicated by the arrow K.
The gemstone specimen holder 49A is also formed with a canoe-shaped aperture 56 whose deepest portion 56A is throughgoing for mounting the gemstone 14 such that its longitudinal axis T is perpendicular to the CCD camera's optical axis 13. and opposite portions of its girdle D are the gemstone's uppermost and lowermost surfaces (see Figure 10A). When so mounted, the gemstone 14 can be positioned within the CCD camera's field of view for enabling die capture of an image of a gemstone's girdle D (see Figure 10B). In this case, the image of the gemstone's girdle D is accompanied by a remark that the girdle is not polished.
With reference now to Figures 11A and 11B. a gemstone specimen holder 49B includes a spur gear arrangement 57 with a band rotated gear 58 for driving a driven gear 59 formed with a throughgoing cylindrical aperture 61. The gemstone 14 can be mounted in the gemstone specimen holder 49B with its longitudinal axis T co-axial with the CCD camera's optical axis 13 and its table A uppermost. thereby enabling the capture of a rotatable image thereof. In addition, a precession-like movable image of the gemstone's table can be captured by combining the movements of the gemstone's rotation with a cyclic tilting about the CCD camera's optical axis 13 indicated by the arrow L.
With reference now to Figure 12, the genistonc 14 can be invertedly mounted in the cylindrical aperture with its cullet B uppermost such that on

-16-
inclination of the gemstone specimen holder 49B relative to the outer frame 41. its pavilion C is uppermost thereby enabling the capture of a rotatable image thereof.
With reference now to Figures 13-13, a gemstone specimen holder 49C is employed with a light source 62 having a light beam 63 with a light beam axis 64 for imaging a registration marking of light diffusing segments 66 (shown exaggerated in Figure 15) inscribed on the gemstone's table A adjacent one of its borders. The gemstone specimen holder 49C includes a U-shaped member 61 including a lower horizontal leg 68. an upright web 69, and an upper horizontal leg 71. The U-shaped member 67 is so dimensioned that on sliding insertion of the lower leg 68 into the middle pair of grooves 29. the upper leg 71 is disposed above the cover 33. The upper leg 71 is provided with a support 72 with an inclined upper surface 73 with a cylindrical recess 74 for receiving a gemstone receiving insert 76 for mounting the gemstone 14 such that its table A is inclined relative to the CCD camera's optical axis 13 at an included acute angle p. The gemstone receiving insert 76 is rotatable about an axis of rotation R, and is provided with a recess 77 for receiving the gemstone 14 such that the gemstone's longitudinal axis T is coincides with the insert's axis of rotation R. The gemstone specimen holder 49C is set up such that the CCD camera's optical axis 13 views a small footprint 78 of about 1 mm diameter located on the periphery of the gemslone's table A whereupon the CCD camera 12 tracks a lmm wide annular path 79 around the gemstone's table's periphery on rotation of the gemstone receiving insert 76. The light source 62 is set up such that its light beam axis 64 intersects the CCD camera's optical axis 13 at the small footprint 78 whereby the perpendicular 79 to the gemstone's table. A thereat coincides with the bisector 81 of the angle between the CCD camera's optical axis 13 and the light source's light beam axis 64. In this arrangement, the gemstone's table A reflects the light beam 63 to dazzle the CCD camera 12 such that the registration marking 66 is discernible by virtue of its light diffusing segments when disposed at the intersection point of the CCD camera's optical axis 13 and light source's light beam axis 64.

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With reference now to figure 16. a gemstone specimen holder 49D is similar to the gemstone specimen holder 49C except that its is employed for imaging a a registration marking inscribed onagemstone's glrdle C. In this case, the specimen gemstone holder 49C further includes a spring biased device 82 for urging against the gemstone's table A.
With reference now to Figures 17A and 17B, a gemstone specimen holder 49E is provided for imaging silhouettes of the gemstone 14 for the purpose of a computer rendered three dimensional wire frame of the gemstone. and a computer rendered three dimensional representation of the gemstone 14 viewable in three dimensional viewing space. The gemstone specimen holder 49E is provided with a Step motor 83 for rotating a spindle 84 whose axis of rotation 86 is perpendicular to the CCD camera's optical axis 13. The spindle 84 terminates at a spindle end 87 extending into a throughgoing aperture 88, and to which a circular gemstone support member 89 can be replaceably attached. The gemstone support member holder 89 includes a reference marking 91 and is employed together with a light difruser 24A having a black spot 24B tor reasons to be described hereinbelow. The gemstone specimen holder 49E is also provided with a calibration square 92 which lies on a plane 93 perpendicular to the CCD camera's optical axis 13 and co-planar with the axis of rotation 86.
The use of the system is now described for the offering for sale of a single new gemstone in the Website and whose portfolio of images is to be displayed on a computerized viewing station and/or a computer terminal which displays visually continuously movable images of a gemstone in the form of a series of computer rendered animated images rather than streaming video images.
A seller of the gemstone scrutinizes the gemstone itself, and determines all the necessary information to be conveyed to a potential buyer including the locations of imperfections. The seller enters into ihe Website under a subscriber number, and enters specific details about a gemstone based on his appraisal, the details including inter alia: its dimensions, its cut. color, size in carats, its clarity, its asking price per carat and details of a certificate, if any.

-18-
The seller selects a suitable gemstone specimen holder and places the gemstone's cullet in the holder's cylindrical aperture whereupon the gemstone is held upright with its table uppermost. The seller slides the gemstone specimen holder into the support block, and adjusts its position such that the center of the gemstone's table is located at the center of the viewing station's screen. The seller adjusts the magnification of the CCD camera such that the image of the gemstone nearly occupies the full screen, and when satisfied with the image, he operates the frame grabber to capture the image under a filename Table Image. The seller can then mark the image with one or more AOIs. for example, as shown in Figure 7B. The seller-repeats the process for capturing near full screen Size still floating images of the gemstone's girdle saved under the filename Girdle Image, the gemstone's pavilion saved under the filename Pavilion Image, and the gemstone's cullet saved under the filename Cullet Image.
The seller executes the following steps for obtaining a pair of complementary digital first and last still images of the gemstone's table for use in displaying a visually continuously tillable image thereof, and a visually continuously precession-like movable image thereof: The seller invokes a Tilting Table sub-routine which requires so-called first and last images of a gemstone's table to be saved under the filenames First Image and Last Image, respectively. The seller pivots the gemstone specimen holder through an acute angle a in the range of about 2° to 8° relative to the CCD camera's optical axis in a first sense, and captures the so-called first image of the gemstone's table under the filename First Table Image. The seller then pivots the gemstone specimen holder through the same acute angle in an opposite sense relative to the CCD camera's optical axis: ' and captures the so-called last image of the gemstone's table under the filename Last Table Image. The seller repeats these steps for obtaining a pair of complementary digital first and last still images of the gemstone's pavilion saved under the filenames First Pavilion Image and Last Pavilion Imaee for use in displaying a visually continuously tiltable image thereof.

-19-
The seller executes the following steps for obtaining a pair of complementary digital left and right images of the gemstone's table for use in displaying a-stereoscopic image tbercof. The-setter invokes a Stereoscopic Image -sub-routine which requires so-called left and right images of a gemstone's table to be saved under the filenames Left Image and Right Image, respectively. The seller repeats the steps described hereinabove for capturing the so-called tillable image of the gemstone's table except that this time the first image of the gemstone's table is saved under the filename Left Image whilst the last image of the gemstone's table is saved under the filename Right Image. In this manner, the two captured images are comparable to the images as seen by a user looking at a stationary object first with one eye only, and then with the other eye only. Alternatively, the right image of the gemstone's table can be captured after the capturing of its left image by a rectilinear displacement of the gemstone specimen holder in the negative X-direction. and then the images are suitably manipulated in X and Y directions by way of a dedicated graphic user interface (GUI) 94 for enabling a clear stereoscopic image to be displayed (see Figure 18).
The seller executes the following steps for obtaining a three dimensional wire frame of the gemstone. and a series of images which are required for rendering a three dimensional representation of the gemstone; The seller invokes a Three Dimensional Representation sub-routine which requires tens of bit map silhouettes of the gemstone, and five or more images of the gemstone from different lines of sight and which include all the different facets of the gemstone. The seller mounts the gemstone on the gemstone support member by a so-called "dry adhesion" technique involving pressing the gemstone's table against the gemstone support member with sufficient pressure that the gemstone is naturally adhesively attached to the gemstone support member. The seller then mounts the gemstone support member on the spindle end with the reference marking in the 12 o'clock position, and replaces the base's original light diffuser with the light diffuser having the large black spot for so-called back illumination of the gemstone. The seller then actuates the motor for rotating the gemstone whereupon preferably

-20-
90 silhouettes are taken at 4° intervals such that most of the gemstone's vertices are captured in the silhouettes (see Figure 19A). The sub-routine then processes the bit maps-using curve fitting techniques, and the like to determine the locations of all of the gemstone's vertices in three dimensional object space to construct a three dimensional, wire frame 95 of the gemstone from its both detected and calculated vertices (see Figure 19B). The three dimensional wire frame can be manipulated in three dimensional viewing space by means of a suitable control device, i.e., a computer mouse, and also has an indication corresponding to the reference marking. Tlie seller then images the calibration square without altering the set up of the system such that the sub-routine can then calculate the external dimensions of the gemstone. and the relative proportions of its different surfaces. To generate the three dimensional representation of the gemstone, the seller images the gemstone from different lines of sight and then superimposes the three dimensional wire frame such that each of the gemstone's facets is correctly superimposed on its corresponding facets as they appear on the images (see Figure 19B). After each such superimposition, the sub-routine builds up a table of bit map information of textures for each gemstone facet.
The potential buyers of gemstones search the inventory of gemstones for sale at the Website in a similar manner as described hereinabove with respect to the already commercially active Websites. However, rather than a potential buyer being presented with a mere list of gemstones which meet his search parameters, in this case, he is presented with a graphic user interface (GUI) 96 showing a nearly full screen size floating lifelike still color image of a gemstone's table of one of the gemstones which met his search parameters which is downloaded from the Website (see Figure 21). In addition, the GUI 96 has a sidebar 97 with relevant details of the gemstone including dimension, cut color, clarity, price, quantity, code. certificate, and seller details.
The GUI 96 also has icons for displaying additional images of the gemstone which are also downloaded from the Website as follows: An icon 98 for displaying the still image of its girdle saved under the filename Girdle Image. An icon 99 for

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displaying the still image of its cullet saved under the filename Cullet Image. An icon 101 for displaying a still image of its pavilion saved under the filename Pavilion Image. An icon 102 for displaying a stereoscopic image of its table saved under the filenames Left Image and Right Image. An. icon 103 for displaying a visually continuously tiJtable image of its table employing the images saved under the filenames First Table Image and Last Table Image where the image is in the form of a series of computer rendered animated still images l(n) each constructed according to the relationship: I(n) = pI(first) ÷ (1-p) I(Iast) where 0
from a continuously changing line of sight directed toward the gemstone (see Figure 20). An icon 107 for displaying a visually continuously movable rotatable image of its pavilion by manipulating the image saved under the filename Pavilion Image in a similar manner for displaying a visually continuously rotatable image of its table. An icon 108 for displaying a visually continuously precession-like movable image I(z) of its table in accordance with a continuously changing line of sight directed toward the gemstone by manipulating the images I(first) and I(last) as foliows I(z) = pI[rot(flrst)] ÷ (l-p)I[rot(last)] where 0
-22-
image and a last direction during the capture of the last image such that the two directions define a pJane therebetween and intersect at an acute angle a; and
An icon 109 for displaying zoom images of one or more of the gemstone's imperfections as shown by Areas of Interest introduced by die gemstone's seller on one or more of the still images of its table, girdle, cullet. and pavilion. An icon 111 for displaying a three dimensional representation of the gemstone viewable in three dimensional viewing space where each of the" representation's facets is textured in accordance with a particular line of sight directed toward the gemstone in accordance with the relationship: F(i)=Sp(j)F(ij) where Sp(j)2=l for j=l to n different textures of the same facet F(i) each taken from, a different line of sight, and p(j) are directional cosines of the line of sight in a predefined Cartesian coordinate system.
Finally, the GUI can also include an icon 112 for displaying a Gem Certificate 113 (see Figure 22) of the gemstone issued by an internationally recognized body, the Gem Certificate including an Issue Number, date of issue, details regarding shape, cut. weight, proportions/measurement, clarity, fluorescence, color and comments. In addition, the Gem Certificate 113 includes one or more of the lifelike color images of the gemstone's major surfaces, i.e. its table, girdle, cullet and pavilion, together with AOIs 114 delimiting boundaries around its imperfections, Alternatively, the images can be replaced by wire frame representations of the gemstone whilst the AOIs can be replaced by arrows 116. and the like for graphically indicating the location of an imperfection. On the basis of a gemstone's portfolio of digital lifelike, color images, together with its Gem Certificate if available, a trained professional has all the necessary information to substantiate the details provided by the seller in respect of a gemstone that he is contemplating to purchase, and also evaluate it? market worth without having to physically scrutinize the gemstone itself.

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While tlie invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention can be made within the scope of the appended Claims. For example, the digital acquisition device can be provided with zooming capabilities for magnifying a gemstone whilst a Gem Certificate for a particular gemstone can be distributed in hard copy to potential buyers in a conventional manner. In additioa. the method for displaying a visually continuously movable image at a computer terminal can be equally applied to any object, as can the method for obtaining a pair of complementary digital left and right images of an object for displaying a stereoscopic image thereof.

24 WE CLAIM:
1. A system for trading in gemstones, each gemstone having a flat
table defining a longitudinal axis perpendicular thereto, a girdle, a
pavilion, and a cullet, the system comprising a plurality of user
terminals for capturing digital lifelike color images of a gemstone, each
user terminal capable of generating the same standard portfolio of digital
lifelike color images of a particular gemstone for enabling a potential
buyer to independently evaluate its market value in accordance with
internationally recognized standards.
2. A system according to Claim 1 wherein a gemstone's portfolio
includes at least one element of the group consisting of:
a floating still image of its table; a floating still image of its pavilion;

25
a floating still image of its girdle; a floating still image of its cullet;
a pair of complementary left and right still images of a gemstone's surface for enabling the display of a stereoscopic image thereof;
a movable image of one or gemstones surfaces;
a three dimensional representation of a gemstone viewable in three dimensional viewing space;
an image of its registration marking;
details of the sizes and relative proportions of a gemstone's surface;

26
a Gem Certificate.
3. A system according to Claim 1 wherein at least one image
includes : an Area of Interest indicating the presence of an imperfection
discernible therein, and/or a color chart.
4. A system according to Claim 2 wherein said movable image is :

27
- a tiltablc image where each computer rendered animated still image I(n) is
constructed according to the relationship I(n) = where
0 - a rotatable image where each computer rendered animated image I(rot) is
constructed according to the relationship:
I(rot) where pixel coordinates or
- a precession-like movable image where each computer rendered animated
image I(z) is constructed according to the relationship: I(z) - pI[rot(first)] - '
(Ip)I[rot(last)] where 0 of the gemstone's surface with the gemstone's longitudinal axis defining a first
direction during the capture of the first image and a last direction during the capture
of ihe last image such that the two directions define a plane therebetween and
intersect at an acute angle a, and
l(rot) where pixel coordinates (/. j)
5. A system according to Claim 2. wherein said three dimensional
representation has facets each textured in accordance with a particular line of sight
directed toward the gemstone in accordance with the relationship: F(i)=S(j)F(ij)
where Sp(j)2=1 for j=1 to n different textures of the same facet F(i) each taken from
a different line of sight, and where p(j) are directional cosines of the line of sight in
a predefined Cartesian coordinate system.
6. A system according to Claim 2. wherein said Gem Certificate comprises at
least one representation of die gemstone in which an imperfection of the gemstone

-28-is discernible, and whose location on at least one of said at least one representation is graphically indicated thereon.
7. A system according to Claim l,option coinprising at least one data storage
device for storing said portfolios of digital lifelike color images.
8. A data storage device storing a plurality of portfolios of digital. lifelike,
color images of gemstones for sale for use in the system of trading in Hemstones
according to any one of Claims 1 to 7.
A method of tradins in eemstones based on the system of any one of Claims 1 to 7 and on the data storage device of Claim 8. enabling one or more potential buyers of gemstones to remotely access the data storage device whereupon each potential buyer can peruse through the portfolio of images of a gemstone which he is contemplating to purchase.' .
10. A user terminal for capturing images of a gemslone. "the user terminal comprising:
a) a base;
b) a support block mounted on said base, 'and supporting a
light-transmissive gemstone bearing member holding a gemstone in a central portion of said support block, said support block substantially shielding the gemstone from ambient light without completely excluding ambient light from said central portion and including an illumination arrangement for illuminating the gemstone from opposing orthogonal directions in a substantially balanced manner, said directions including a first axial direction for illuminating a first major surface of said gemstone bearing member, a second axial direction for illuminating a second major surface of said gemstone bearing member opposite to said first major surface, and a third direction for radially illuminating said central portion; and

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a digital image acquisition device with an optical axis, and being mounted on said base for capturing an image of the illuminated gemstone through an aperture formed in said support block facing said first major surface of said gemstone bearing member.
11. A user terminal according to Claim 10. wherein said support block has an
open-ended box-like shape with a top surface, a bottom surface and a pair of
opposing substantially parallel walls.
12. A user terminal according to either Claim 10 11, wherein said support
block has the following internal dimensions: length 6±15% cm. width 5±15% cm.
and height 5±15% cm.
13. A user terminal according to any one of Claims 10 to 12, wherein said
illumination arrangement includes at least one annular diffused whito light source
for illuminating in at least one of said first and second axial directions.
14. A user terminal according to any one of Claims 10 to 13, wherein said
illumination arrangement includes light reflective portions for reflecting light
radially towards said central portion.
15. A user terminal according to any one of Claims 10 to 14, wherein said
gemstone bearing member includes a carriage with an outer frame for being
slidably received in a pair of opposite grooves, and a pair of support members
pivotably mounted on said outer frame for assuming a first position substantially
flush with said outer frame and a second position subtending an acute angle relative
to said outer frame.
16. A user terminal according to Claim 15, wherein said outer frame includes a
pair of opposite support members, at least one of said support members having a
longitudinally extending slit for frictionally precluding free uncontrolled movement of said carriage in a pair of grooves.

30
17. A user terminal according to any one of Claims 10 to 15. wherein said
gemstone bearing member comprises a flat, light-transmissive, glass slide-like
gemstone specimen holder with at least one throughgomg aperture for removably
receiving a portion of a gemstone's body for mounting the gemstone in a
predetermined position.
18. A user terminal according lo Claim 17, wherein said aperture has the shape
of a cylinder or the shape of a canoe.
19. A user terminal accordins to any one of Claims 10 to 18, wherein said
gemstone bearing member comprises a flat, light-transmissive, glass slide-like
gemstone specimen holder with a rotatably mounted member for supporting a
gemstone. which may include a gear spur arrangement for rotating said rotatably
mounted member.
20. A user terminal according to any one of Claims 10 to 14, further comprising
a gemstone specimen holder with a rotatable gemstone specimen holder for rotating
a gemstone with its girdle facing said digital image acquisition device.
21. A user terminal according to.Claim 20: wherein said gemstone specimen
holder includes a calibration square lying in a plane perpendicular to said optical
axis and co-planar with an axis of rotation of said rotatable gemstone specimen
holder.
22. A user terminal according to either Claim 20 or 21. wherein said gemstone
specimen holder is replaceable.
23. A user terminal according to any one of Claims 10 to 14, further
comprising:
(d) a light source having a light beam with a light beam axis intersecting said optical axis at an intersection point, and defining a bisector therebetween; and

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(e) a gemstone supporting member for supporting a gemstone such that said bisector coincides with the perpendicular of the portion of its surface; and being selectively displaceable relative to said intersection point whereby the gemstone's surface is capable of being scanned along a predetermined scanning path for enabling the detection of the location of a gemstone's registration marking.
24. A user terminal according to Claim 23. wherein said gemstone supporting
member is slidingly supported in said support block.
25. A user terminal according to either one of Claims 23 or 24, wherein said
gemstone supporting member includes a rotatably mounted gemstone receiving
insert for mounting the gemstone.
26. A user terminal according to Claim 25, wherein said gemstone receiving
insert is replaceable.
27. A user terminal according to any one of Claims 23 to 26, further comprising
an urging member for securing a gemstone in said gemslone support member.
28. A gemstone examination device for enabling the detection of the location of
a gemstone's registration marking, the registration marking including a series of
light diffusing segments located on a flat polished surface of the gemstone defining
a longitudinal axis perpendicular thereto, the gemstone examination device
comprising:

(a) a light source having a light beam with a light beam axis;
(b) a magnifying optical device having an optical axis intersecting said light
beam axis at an intersection point, and defining a bisector therebetween;
and
(c) a gemstone supporting member for supporting a gemstone such that said
bisector coincides with the perpendicular of the portion of the
gemstone's surface located at said intersection point, and being

32
selectively displaceable relative to said intersection point whereby the gemstone's surface is capable of being scanned along a predetermined scanning path.
29. A gemstone examination device according to Claim 28. wherein said
gemstone supporting member includes a rotatably mounted gemstone receiving
insert for mounting the gemstone.
30. A gemstone examination device according to either Claim 28 or 29, wherein
said gemstone receiving insert is replaceable.
31. A gemstone examination device according to any one of Claims 28 to 30.
further comprising an urging member for securing a gemstone in said gemstone
support member.
32. A gem certificate for a gemstone. the gem certificate comprising at least one
representation of the gemstone in which an imperfection of the gemstone is
discernible, and whose location on at least one of said at least one representation is
graphically indicated thereon.
33. A sem certificate according to Claim 32, wherein said at least one
representation includes at least one element from the group consisting of:
a digital lifelike color image of the gemstone;
a wire frame representation of the gemstone;
an Area of Interest delimiting a boundary around an imperfection.
34. A method for displaying a visually continuously movable image of a
gemstone's surface at a computer terminal remote from a database, the method
comprising the steps of:
(a) downloading bit map information regarding a gemstone from the database to the computer terminal;

33
(b) generating from the bit map information at the computer terminal an
on-the-fly computer rendered animated still image of the gemstone from a
particular line of sight directed toward the gemstone; and
(c) refreshing the computer rendered animated still image of the gemstone
from different lines of sight directed toward the gemstones as indicated by a
potential buyer of the gemstone at his computer terminal thereby displaying
a series of computer generated animated still images of the gemstone
perceived as a visibly continuously movable image by the potential buyer.
35. A method for displaying a movable image of a gemstone's surface according to Claim 34. wherein said movable image is:
- a tillable image where each computer rendered animated still image I(n) is
constructed according to the relationship I(n) = pI(firsl) ÷ (1-p) I(Iast) where 0 surface with the eemstone's longitudinal axis defining a first direction during the
capture of the first image and a last direction during the capture of the last image
such that the two directions define a plane therebetween and intersect at an acute
angle a; or
- a rotatable image where each computer rendered animated image I(rot) is
constructed according to the relationship;

- a precession-like movable image where each computer rendered animated
image l(z) is constructed according to the relationship: I(z) = pI[rot(first)] ÷
(l-p)I[rot(Iast)] where 0 of the gemstone's surface with the gemstone's longitudinal axis defining a first
direction during the capture of the first image and a last direction during the capture
of the last image such that the two directions define a plane therebetween and
intersect at an acute angle a. and

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I {rot) where pixel coordinates
- a visually continuous movable image of a three dimensional representation
of a gemstone viewable in three dimensional viewing space where each of the
representation's facets is textured in accordance with a particular line of sight
directed toward the gemstone in accordance with the relationship: F(i)=Sp(j)F(ij)
where Sp(j)2=l for j=l to n different textures of the same facet F(i) each taken from
a different line of sight, and p(j) are directional cosines of the line of sight in a
predefined Cartesian coordinate system.
36. A method for obtaining af a streoscopic image of a gemstone"s table, the
method comprising the steps of:
(a) mounting the gemstone in the field of view of a digital image
acquisition device;
(b) acquiring a left image of the gemstone;
(c) .displacing the gemstone specimen holder relative to the image
acquisition device's field of view; and
(d) acquiring a right image of the gemstone.
37. A method according to Claim 36. wherein step (c) includes:
- translating the gemstone by a distance substantially corresponding to the
separation between the eyepieces of a binocular microscope, or
- translating and rotating the gemstone so that the gemstone's longitudinal
axis defines two intersecting directions in the axis' extreme positions.

A system for trading in gemstones, which is having a flat table defining a longitudinal axis perpendicular thereto, a girdle, a pavilion, and a cullet The system comprises a plurality of user terminals for capturing digital lifelike color images of a gemstone, each user terminal capable of generating the same standard portfolio of digital lifelike color images of a particular gemstone for enabling a potential buyer to independently evaluate its market value in accordance with internationally recognized standards.

Documents:

00603-cal-2000 abstract.pdf

00603-cal-2000 claims.pdf

00603-cal-2000 correspondence.pdf

00603-cal-2000 description(complete).pdf

00603-cal-2000 drawings.pdf

00603-cal-2000 form-1.pdf

00603-cal-2000 form-18.pdf

00603-cal-2000 form-2.pdf

00603-cal-2000 form-26.pdf

00603-cal-2000 form-3.pdf

00603-cal-2000 form-5.pdf

00603-cal-2000 letters patent.pdf

00603-cal-2000 priority document.pdf

00603-cal-2000 reply f.e.r.pdf

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Patent Number

207104

Indian Patent Application Number

603/CAL/2000

PG Journal Number

21/2007

Publication Date

25-May-2007

Grant Date

23-May-2007

Date of Filing

27-Oct-2000

Name of Patentee

DIAMOND AND JEWELRY-4-U LTD.

Applicant Address

54 BEZALEL STREET, YAHALOM BLDG., RAMAT-GAN 52521, ISRAEL

Inventors:

#	Inventor's Name	Inventor's Address
1	HAUSMAN YGAL	36 MIKVE ISRAEL STREET, HOLON 58274, ISRAEL

PCT International Classification Number

G 02 B 21/84

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	132648	1999-10-29	Israel
2	134664	2000-02-22	Israel