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Publication numberUS3740142 A
Publication typeGrant
Publication dateJun 19, 1973
Filing dateJun 16, 1970
Priority dateAug 24, 1969
Also published asDE2031065A1, DE7023622U
Publication numberUS 3740142 A, US 3740142A, US-A-3740142, US3740142 A, US3740142A
InventorsTakubo Y
Original AssigneeFumio Suruki, Yoshihiko Takubo
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for discriminating and/or identifying jewels
US 3740142 A
Abstract
A novel method for testing materials such as jewels having optical properties such as transparency, reflection, and refraction, in commercial basis, and an apparatus for practicing the method are proposed. The apparatus comprises an enclosure forming a dark room in which the material such as a jewel is tested, means for holding and positioning the material at a selected position inside of the dark room, a beam of electromagnetic radiation such as light is directed onto the material preferably from the culet side of the material, and a photographic material, preferably placed on the crown side thereof, for recording an image of the electromagnetic radiation distribution of the beam passed through on the material.
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Description  (OCR text may contain errors)

United States Patent [1 1 Takubo 3,740,142 June 19, 1973 APPARATUS FOR DISCRIMINATING AND/0R IDENTIFYING JEWELS Primary ExaminerR0na1d L. Wibert Assistant Examiner-Paul K. God/win [75] Inventor: Yoshihiko Takubo,Tokyo,Japan Atmmey-LemeL David & Humbug T C A R T S B A 1 7 5 .I 0 k ..l m n .0 Ym a J k 0 LR W 0 r h .7 U19 8 ml 6 0M qmme uam FTJ e n In 1 0 w h A c 1 .1 3 2 7 2 r1 .1.

A novel method for testing materials such as jewels 211 Appl. No.: 46,724

having optical properties such as transparency, reflec- 30 Foreign Application priority Data tion, and refraction, in commercial basis, and an appa- Aug 24 1969 Japan 44/80406 ratus for practicing the method are proposed. The ap paratus comprises an enclosure forming a dark room in Cl- I the material Such as a jewel IS tested, means for holding and positioning the material at a selected posi- [5 l] Int. Cl. G0l n l 3 inside Ofthe dark room a beam Ofelectromagnetic 581 Field of 356/30 76 31 radiation Such as light is directed the material preferably from the culet side of the material, and a photographic material preferably placed on the crown [56] References Cited UNITED STATES PATENTS 12/1964 Chan...........t....

side thereof, for recording an image of the electromagnetic radiation distribution of the beam passed through on the material.

356/76 356/30 4/1956 Zeimnger.............................. 356/30 6 Claims, 9 Drawing Figures FOREIGN PATENTS OR APPLICATIONS 3,160,748 1,700,497 1/1929 Heitzler 2,742,813

Patented June 19, 1973 4 Sheets-Sheet 1 F/GZ Patented June 19, 1973 4 Sheets-Sheet z Patented June 19, 1973 4 Sheets-Sheet 3 11/! III IYIITIIP77 I/l/ Patented June 19, 1973 4 Sheets-Sheet 4 APPARATUS FOR DISCRIMINATING AND/OR IDENTIFYING JEWELS BACKGROUND OF THE INVENTION This invention relates to a method and device for discriminating and identifying materials having optical properties such as jewels.

Heretofore, the discrimination or identification of the materials having optical properties such as jewels has been carried out only by skilled craftsmen who have long experience in the art. However, the method relying on the craftsmans experiences cannot exhibit any visible ground for the judgement, and, for this reason, the decision cannot be persuasive to all of the concerned personnel.

Of course, it has also been known that the materials having optical properties such as jewels can be discriminated or identified employing crystallographical techniques. For instance, the material such as jewels may be tested employing X-rays, ultraviolet rays, or polarized light, and the reflected, refracted, or dispersed rays or visible light may be recorded on a photographic substance or film for the subsequent inspection. However, such a procedure is carried out rather for determining the kind of the materials or for determining the crystallographical structure, and the method and devices required for practicing such a procedure are too much complicated and costly for simply discriminating or identifying the material in the commercial basis.

SUMMARY OF THE INVENTION Therefore, the primary object of the present invention is to provide a novel method and device for testing materials having optical properties such as jewels for the purpose of mostly discrimination and identification of the materials in a commercial basis.

Another object of the present invention is to provide a novel method and device for testing materials having optical properties without relying on the craftmans skill or experiences.

Still another object of the present invention is to provide a novel method and device for testing materials having optical properties such as transparency, reflection, and refraction without requiring any elaborate procedure or devices.

Still another object of the present invention is to provide a novel method and device for testing materials such as jewels whereby a visible record indicative of any slight degree of difference inherent in the material is obtained for preservation and subsequent comparison.

A further object of the present invention is to provide a novel method and device for testing materials such as jewels wherein the material to be tested can be instan taneously set to the position, and a record can be obtained even if the material is mounted on a ring or the like ornament.

A yet further object of the present invention is to provide a novel apparatus for testing materials such as jewels, wherein all of the required components are combined in one unit, whereby a visible record of the material can be obtained instantaneously.

These and other objects of the present invention can be achieved by a novel method for testing materials such as jewel having optical properties such as transparency, reflection, and refraction, which method comprises shining a beam of electromagnetic radiation,

preferably of light rays in a range of wavelength reflectable and refractable by the material, onto the material such as a jewel; and recording, on a photographic mate rial, an image of distribution of the electromagnetic radiation beam passed through on the material.

Preferably, the photographic material such as a photographic film may be placed on the crown side of the jewel having a plurality of facets, and the electromagnetic radiation beam such as light rays may be shone on the jewel from the culet side thereof.

Preferably, the photographic material is a Polaroid film which can be instantaneously developed and printed, and the electromagnetic radiation beam is obtained from a miniature lamp of a known characteristic.

In another aspect of the invention, the above described objects are also achieved by a novel device for testing materials such as jewels having a plurality of facets, the device comprising an enclosure forming a dark room, means for holding and positioning the material inside of said enclosure, a source of electromag netic radiation beam directed onto the material to be tested, and a photographic material for recording an image of the electromagnetic radiation distribution of the beam passed through the material.

Preferably, the above mentioned means for holding and positioning the material to be tested is made adjustable as to the position from the outside of the enclosure.

Alternatively, the above mentioned means for holding and positioning the material is made into a fixed type, and a separate focusing means controllable from the outside of the enclosure may be provided inside of the enclosure.

Preferably, a shutter system for rendering an ade quate exposure time on the photographic material be provided inside of the enclosure, and a shutter button may be provided on the front panel of the enclosure.

Likewise as in the method according to the present invention, the photographic material such as a photographic film is preferably placed on the crown side of the jewel having a plurality of facets, and the electromagnetic radiation beam is preferably shone onto the jewel from the culet side thereof.

Preferably, the above described beam electromagnetic radiation source may be made in the form of a miniaturized lamp attached on an end of the positioning device for the material in a manner aligning with the material, so that the light beam from the miniature lamp is shone on the jewel.

The nature, principle, and utility of the invention will be better understood from the following description with respect to preferred embodiments thereof, when read in conjunction with the accompanying drawing, wherein like parts are designated by like reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a schematic diagram to be employed for explaining the fundamental principle of the present invention;

FIG. 2 is a diagram showing a distribution of reflected or refracted light beams obtained by a device schematically indicated in FIG. 1;

FIG. 3 is another schematic diagram to be employed for explaining the fundamental principle of the present invention;

FIG. 4 is also a diagram showing another distribution of reflected or refracted light beams obtained by a device schematically indicated in FIG. 3;

FIG. 5 is a perspective view of an apparatus which constitutes an embodiment of the present invention;

FIG. 6 is also a perspective view showing the same apparatus illustrated in FIG. 5, which is partly frustrated so that the inside components can be seen more clearly;

FIG. 7 is another perspective view showing a construction of a jewel positioning head employed in the apparatus shown in FIGS. 5 and 6;

FIG. 8 is a partial sectional view showing an apparatus which constitutes another embodiment of the present invention; and

FIG. 9 is a sectional view rather schematically showing another construction of the jewel holding and positioning device which also may be employed in an apparatus according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION Referring now to FIG. 1 showing an example of a device for practicing the method according to the present invention for the purpose of explanation of the fundamental principle of the invention, there is indicated a cylindrical body 1 having a top cover 2 and a bottom plate 3 so that a dark room is thereby formed. Inside of the cylindrical body 1, a transparent plate 4 having a glassy surface to mount a jewel A is provided. A source of an electromagnetic radiation, which is a visible light in this example, is formed into a unit 5 including a lamp 6, a condenser lens 7, and a small hole 8 for passing a light beam.

The light source 5 is provided through the top cover 2 so that a light beam Fl is shone onto the jewel A fixed on a jewel mounting piece 9 placed on the transparent plate 4. A photographic material such as a film is provided on the inside surface of the cylindrical body 1, and the light rays reflected or refracted from the jewel A are projected on the film 10 as indicated by arrows F-2 through F-7. Thus, a plurality of images for the reflected or refracted light rays through the jewel A are formed on the film 10. If the film 10 is thereafter withdrawn and developed, images such as illustrated in FIG. 2 are fixed on the film 10, so that the film may be preserved for the subsequent comparison for the identification or discrimination of the jewel.

In the above description, although the jewel A has been described as being shone from the crown side thereof, it is found rather preferable that the jewel is shone from the culet side, and such an example is shown in FIG. 3.

In FIG. 3, all of the members such as the cylindrical dark room 1, a transparent plate 4 having a glassy surface, and a light source 5 having a lamp 6, a condenser lens 7, and a small hole 8 are quite similar to those indicated in FIG. 1. However, in this example of the device for practicing the method according to the present invention, the jewel A is placed directly on the transparent plate 4, with the crown directed downward contacting with the transparent plate 4, so that the light beam F-l passing through the hole 8 of the light source unit 5 is shone on the culet side of the jewel A. Furthermore, the photographic materials such as films are attached not only on the inside surface of the cylindrical body 1 but also on the inside surface of the bottom plate 3.

When the images fixed on the film 10 in FIG. 2 are compared with the images fixed on the films 10 and 10a in FIG. 4, it is found that more detailed features characterizing the specific jewel can be seen in the films 10 and 10a in FIG. 4 and more specifically in the film 10a.

As a result of the findings, in all of the hereinafter described examples of the jewel identifying or discriminating devices for practicing the method according to the present invention in more practicable form or manner, the light beam is preferably, but not limited thereto, shone on the jewel from the culet side of the jewel. Furthermore, although in the above described principle or fundamental concept of the present invention, an electromagnetic radiation, in the form of visible light rays, has been employed for the simplicity of the explanation, another form of electromagnetic radiation such as infrared rays or ultraviolet rays may also be employed for a specific field of application, so far as the rays may be reflected or refracted by the facets of the jewels. Such an application has been found exclusively useful in discrimination or identification of the jewels having, for instance, a fluorescent or phosphorescent nature, or when a jewel having a spectrographic singularity is discriminated employing the reflected or refracted light beam in a specific range of the wave length.

Furthermore, although the fundamental principle or concept of the present invention has been explained with respect to simplified examples of the devices which are employed for practicing the concept, it would be apparent that the invention is not limited to those devices, but it resides in the method of discriminating and identifying materials having optical properties such as jewels comprising the procedures of shining a beam of electromagnetic radiation onto the material, and recording on a photographic material, an image of the electromagnetic radiation showing the distribution of the electromagnetic radiation reflected or refracted from the material to be tested, and also in the constructions of the devices for practicing the method, which will be described hereinbelow with reference to FIGS. 5 through 9.

In a device shown in FIGS. 5 and 6, which constitutes a preferred embodiment of the present invention, there is provided an enclosure or casing generally indicated by a reference numeral 10. On the front panel 1 l of the casing 10, a position adjusting knob 13 for the material such as ajewel, a voltage adjusting knob 14 for the light source, a power switch 15 for energizing the lighting system, an indicating light 16 for the energization of the system, and a shutter push-button 17 for photographing the image reflected or refracted from the material to be tested are provided. On the rearward portion 12 from the above described front panel 11 of the casing 10, a recessed portion generally indicated by a numeral 18 is provided. A viewer having a hood 20 and a focusing glass 21 as shown in FIG. 6 or a pack of photographic films (not shown) may be inserted in the recessed portion 18, and may be fixed in the position by means of snapping projections 19. Otherwise, the rearward portion 12 of the casing 10 may also be constructed in such a manner that it adapts to receive the viewer having a hood 20 and a focusing glass 21 and/or a package of the Polaroid films which may be fixed in the position by means of a stopper 22 as shown in FIG. 6.

Inside of the enclosure or casing 10, there is provided a jewel positioning device comprising, for instance, a positioning arm 30, a head 31, and a screw-threaded shaft 32. The above-mentioned jewel position adjusting knob 13 is attached on one end of the screw-threaded shaft 32, the other end of which is received rotatably in a recessed pad 33 fixed to the bottom plate of the casing 10. The screw threaded on the shaft 32 engages the female screw threaded inside of a hole provided at one end of the jewel position adjusting arm 30, so that when the knob 13 is rotated in either of the directions, the entirety of the jewel positioning device is raised or lowered relative to the focusing glass or the surface of the photographing film.

At the other end of the jewel positioning arm 30, a jewel positioning head 31 is detachably fixed, for instance, by means of machine screws (not shown). The jewel positioning head 31 may take various forms or construction in accordance with the requirements and ornaments bearing the jewel. Accordingly, it should be understood that the positioning head 31 shown in FIG. 6 is a typical one adapted for mounting a ring 2 embedded by the jewel 1 and having a hole through which a light beam may pass through the ring to the culet side of the jewel l. A miniature lamp 35 is included inside of the jewel positioning head 31 at a position aligning the central axis of the jewel 1 embedded in the ring 2.

In FIG. 7, the construction of the jewel positioning head generally indicated by the numeral 31 is indicated in more detail. In this example, the jewel positioning head 31 comprises, beside of the main body, a ring supporting member 36 having a ring stopper 36a, and a machine screw having a knob 37 for adjusting the position of the ring supporting member 36 to suit to the size of the ring 2 bearing the jewel 1. The above mentioned miniature lamp 35 is included inside of a chamber (not shown) formed at one end of the jewel positioning head 31, and is covered by a covering piece 34 having a central hole 34a and detachably mounted on the positioning head 31. The central hole 34a of the covering piece 34 is so formed that it may be easily abutted in alignment with the aforementioned hole provided through the ring 2 just under the position wherein the jewel 1 is embedded or supported.

An electric power system including a voltage adjusting means is included in the device for lighting the above mentioned miniature lamp 35, and energized or deenergized by means of the above described power switch 15, with such a condition being indicated by the indicator light 16, both mounted on the front panel 11 of the casing 10. The voltage adjusting means may be constructed in the form of a transformer T included inside of the casing as shown in FIG. 6, and the output voltage of the transformer may be adjusted by the voltage adjusting knob 14.

Furthermore, the device may also include a shutter system rendering an adequate period of exposure on the photographic material such as a film, although such shutter system is not indicated in the drawings because it constitutes no part of the present invention, and the operation of the shutter system may be controlled by the shutter button 17 provided on the front panel 1 1 of the casing 10. Of course, the shutter system may take a form of an electric timer for supplying a pulse current to the lamp 35 if an adequate consideration is paid as to the intensity of the current and the period for the duration of the current.

In FIG. 8, there is indicated a cross-sectional view of a device for discriminating and identifying materials having optical properties such as jewels, which constitutes another embodiment of the present invention. Although merely a part of the device required for the explanation of the difference of this embodiment to the above mentioned embodiment is indicated in the draw ing, it should be noted that other members not indicated in the drawing are all similar to those described in the embodiment of FIGS. 5 and 6.

In this embodiment of the invention, the focusing of the image of the jewel on the focusing glass 21 or on the surface of the photographic film (not shown) is achieved by a focusing lens system including focusing lenses 40, and a lens supporting arm 41 which is engaging with the screw threaded shaft 32 controlled by a knob 13, acting at this time as a focusing knob. Be cause of the provision of a member not shown in the drawing, the lateral movement of the focusing arm 41 is prevented, and the focusing lenses 40, 40 can be moved only in the upward or downward direction, so that a sharp image of the jewel can be obtained on the focusing plane despite of the jewel 1 supported by a ring 2 is fixedly mounted on a jewel mounting unit.

More specifically, the jewel mounting unit has a jewel mounting main body 50 the lower end of which is detachably fixed to a mounting socket 51. The upper end of the main body 50 is preferably bent at right-angle, as indicated in FIG. 8, and a lamp accommodating chamber having a cover 53 is provided at an end portion thus bent perpendicularly. The cover 53 is detachably mounted over the lamp 35 mounted on a socket provided at the bottom of the chamber, and a chamfered or a stepped hole 53a is cut through the cover 53.

I A rubber ring 54 having a central hole of a substantially equivalent diameter to the narrower diameter of the stepped hole 53a is inserted into the larger diameter portion of the stepped hole 53a, so that a resilient touch against the inside surface of the ring 2 may be obtained. On an intermediate portion of the jewel mounting main body 50, a ring supporting pad 52 is slidably supported, so that the position of the pad 52 may be adjusted for a desired size of the ring 2 by manipulating a projected end portion 52a of the ring supporting pad 52. In this case also, the lamp 35 and the hole through the cover 53 and the rubber ring 54 are aligned with a hole through the ring 2 just under the jewel 1, so that a light beam may be projected to the culet side of the jewel 1.

I Still another embodiment of the jewel positioning device which is employable in the device for identifying or discriminating the jewl is indicated in FIG. 9 rather schematically and as a sectional view taken along the axis of the assembly. This jewel positioning device is intended for positioning the jewel l which is not mounted on a ring.

Since, in this case, the jewel must be clamped firmly and held accurately in its position, a jewel clamping unit generally designated by a numeral is employed. The jewel clamping unit 60 comprises a required number of claws 61 for holding the jewel 1, a cylindrical member 62 joined to the lower ends of the claws 61 and a mounting screw thread is cut on the lower surface thereof, a sleeve 63 slipped over the cylindrical member 62 and having stepped inside holes of larger and a smaller diameter, and a coiled spring 64 slipped over the cylindrical member 62 so that the upper end of the coiled spring 64 abuts the stepped annular surface inside of the sleeve 63.

The screw threaded portion near the lower end of the cylindrical member 62 is driven into a mating hole provided in a mounting member 65 of the jewel clamping unit which is detachably coupled to a hoisting and descending member 66. The hoisting and descending member 66 may have any cross-sectional configuration, but preferably rectangular, and a collar 66a for limiting the upward movement thereof is provided on the surface at an intermediate position along the length. On one side surface of the member 66 below the collar 66a, a rack 66b and a pinion 67 are provided. The hoisting and descending member 66 is passed through a mating opening provided through a fixed member 70. A miniature lamp 35 is accommodated in the cylindrical member 62 and an electrical power system is connected to the lamp 35.

As is apparent from the above described construction, the jewel 1 may firstly be inserted between the claws 61, 61 of the jewel clamping unit 60 when the sleeve 63 is pushed down against the resilience of the coiled spring 64 and the claws 61, 61 are separated outwardly by their own resilience. By releasing the sleeve 63 thereafter, the jewel 1 is firmly clamped by the claws 61, 61 which are compressed by means of the sleeve 63 pushed upwards under the resilience of the coiled spring 64.

After the jewel 1 is firmly clamped as described above, the hoisting and descending member 66 is hoisted or descended under the action of the pinion 67 and the rack 66b, the pinion 67 being rotated through any of the conventional means from the jewel positioning knob (not shown), so that a sharp image of the reflected or refracted light spots may be obtained on the focusing plane 21.

Although the present invention has been described in connection with preferred embodiments of the invention, it will be apparent to those skilled in the art that various modifications and alterations be carried out without departing the spirit and scope of the present invention.

For instance, the arrangement of the jewel positioning or focusing knob, the voltage adjusting knob, or the like provided on the front panel of the device may be utterly changed from those indicated and described in this invention, or even the front panel itself may be eliminated, and the required controlling knobs or the like may be arranged on a side panel or any other suitable positions.

Furthermore, although the jewel positioning unit has been described as merely adjustable of the vertical position of the jewel, it may also be modified so that the jewel may be turned around of the axis at a desired angle.

In consideration of the above described facts, the true spirit and the scope of the present invention are defined as follows.

What is claimed is:

1. An apparatus for discriminating and identifying materials having optical properties, which comprises:

a light-proof enclosure having side walls and a bottom portion and having located therein, holding means for holding and positioning the material, said holding means including a transparent plate supported by the side walls of the lightproof enclosure:

a light source, a beam of which is directed onto the material to be tested;

holding means for holding a photographic material along the side walls of the light-proof enclosure;

and a photographic material for recording an image of the spectral light distribution of the beam passed through the material, held in place along the walls of the light-proof enclosure by said holding means and disposed along the bottom of the light-proof enclosure.

2. An apparatus according to claim 1 wherein the photographic material is placed near the holding means for holding and positioning the material.

3. An apparatus according to claim 1 wherein said holding means for holding and positioning the material to be tested is adjustably positioned within said enclosure to permit adjustment in distance between said material and the photographic material for recording.

4. An apparatus according to claim 3 and further including control means positioned outside said enclosure and connected to said holding means for adjusting said holding means from outside said enclosure.

5. An apparatus according to claim 3 wherein a shining time of the light source can be adjusted from the outside of the enclosure, said shining time being instantaneously a time of exposure to record a specific character of the spectral light passed through the jewel on a photographic material.

6. An apparatus according to claim 5 wherein the intensity of the light source can be varied from outside of the enclosure.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1700497 *Apr 28, 1927Jan 29, 1929Frank HeitzlerApparatus for use in identifying precious stones
US2742813 *Oct 17, 1952Apr 24, 1956Zeininger Henry PercyProjection apparatus for displaying precious stones
US3160748 *Jun 28, 1962Dec 8, 1964Chan Frank LSpherical goniometer head and adapter
SU122613A * Title not available
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3867032 *Mar 8, 1974Feb 18, 1975Diharo Diamanten Handels CompaArrangement for objectively evaluating characteristics of gems, particularly diamonds
US3947120 *Oct 2, 1974Mar 30, 1976Yeda Research And Development Co. Ltd.Gem identification
US3985454 *Mar 14, 1975Oct 12, 1976NasaWindow defect planar mapping technique
US4763986 *Nov 24, 1986Aug 16, 1988Sego Marvin AIlluminated jeweler's loupe
US5196966 *Jun 27, 1991Mar 23, 1993Masayo YamashitaMethod and implement for observing or photographing gem such as diamond
US5260763 *Feb 16, 1990Nov 9, 1993Masayo YamashitaInstrument for observing jewels' brilliance as diamond, and method of taking photographs with said instrument
US5835205 *Feb 10, 1997Nov 10, 1998C3, Inc.Optical testing system for distinguishing a silicon carbide gemstone from a diamond
US6308891May 5, 1999Oct 30, 2001T.I.D. (The Identifying Diamond) Inc.Jewelry identification
US6450402Sep 29, 1999Sep 17, 2002T.I.D. (The Identifying Diamond) Inc.Identification device
US7000760 *Apr 3, 2003Feb 21, 2006Lau Anson WJewelry box with a viewer
US7193694May 2, 2005Mar 20, 2007William UnderwoodMethod for grading gemstone cut and symmetry
EP0412168A1 *Feb 16, 1990Feb 13, 1991Yamashita, MasayoInstrument for inspecting brilliance of jewels such as diamond and photographing of jewels therewith
EP0442065A2 *Dec 4, 1990Aug 21, 1991Kinsaku YamashitaInstrument for observing jewels brilliance as diamond, and method of taking photographs with said instrument
EP0464824A2 *Jul 4, 1991Jan 8, 1992Kinsaku YamashitaMethod and implement for observing or photographing GEM such as diamond
WO1995011447A1 *Oct 18, 1994Apr 27, 1995Hanna CanGem viewing and manipulation apparatus
WO1997004303A1 *Jul 22, 1996Feb 6, 1997Gersan EtsExamining a diamond
Classifications
U.S. Classification356/30, 356/302, 356/239.1
International ClassificationG01N33/38, G02B27/00, G01B11/24, G03B15/00, A44C17/00, G01N21/87
Cooperative ClassificationG01N33/381, G03B15/00, G01N21/87
European ClassificationG01N21/87, G01N33/38B, G03B15/00