Manual of U.S. Patent Classification
as of June 30, 2000

Class
356
OPTICS: MEASURING AND TESTING

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Subclass definitions may be accessed by clicking on the subclass number, below.

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Subclass		Title
ClassTitle		===> OPTICS: MEASURING AND TESTING
2		CONTOUR PLOTTING
3		RANGE OR REMOTE DISTANCE FINDING
3.01		. Triangulation ranging to a point with one projected beam
3.02		. . Using photodetection with a fixed axial line of sight
3.03		. . Using a source beam with a fixed axial direction or plane
3.04		. . . With a single staring photodetector having one element
3.05		. . . . Having moving receiver optics
3.06		. . . With a single photodetector having multiple elements
3.07		. . . . Having electronic scanning of the photodetector
3.08		. . . With at least one paired set of staring photodetectors
3.09		. . Requiring scanning of a source beam
3.1		. Triangulation ranging to a point with two or more projected beams
3.11		. . Using photodetection at the source station(s)
3.12		. . Using photodetection remote from the source station(s)
3.13		. Triangulation ranging with photodetection, but with no projected beam
3.14		. . Using at least a pair of viewing axes
3.15		. . . With one viewing axis fixed
3.16		. . . With moving optical elements in all viewing axes
4.01		. With photodetection
4.02		. . Of a simulation or test
4.03		. . Of focused image size or dimensions
4.04		. . Of degree of defocus
4.05		. . Of focal point search
4.06		. . Of differential amplitude at two source or detector distances
4.07		. . Of intensity proportional to distance
4.08		. . Of height relative to a light plane
4.09		. . Of light interference fringes
4.1		. . . Having different frequency sources
5.01		. . Of pulse transit time
5.02		. . . Having return coincide with swept display or detector
5.03		. . . Having one or more return pulse gates or windows
5.04		. . . . Including a displayed image
5.05		. . . Having pulse transmission trigger significance
5.06		. . . . Including optical pick-off of transmission start
5.07		. . . . . With specific counter type timing of returns
5.08		. . . . Including specific counter type timing of returns
5.09		. . Of frequency difference
5.1		. . Of CW phase delay
5.11		. . . Having multiple carrier or modulation frequencies
5.12		. . . . Including an alternating reference path
5.13		. . . Having an alternating reference path
5.14		. . . Having polarization discrimination
5.15		. . . Having specific IF mixing of returns
6		. Instrument condition testing or indicating
7		. Periscope or offset type
8		. With view finder
9		. Base line instrument (i.e., base is a part of instrument)
10		. . With filter or light valve
11		. . Range finder combined with height finder
12		. . Stereoscopic
13		. . . Ortho-pseudo type
14		. . . Stationary measuring marks
15		. . Length of base line variable
16		. . Image displaced by moving refracting element
17		. . Image displaced by rotating reflecting element
18		. . With mounting, supporting, adjusting, or folding structure
19		. . Prism structure for determining coincidence
20		. External basis type
21		. . Object size or distance known
22		. . . With displaced images
23		MOTION STOPPING (E.G., STROBOSCOPES)
24		. Periodically moving reflecting or refracting element
25		. Periodically moving light interrupting element
26		. . Vibrating or oscillating element
27		VELOCITY OR VELOCITY/HEIGHT MEASURING
28		. With light detector (e.g., photocell)
28.5		. . Of light interference (e.g., interferometer)
29		OPTICAL ELEMENT OR RETICLE RESPONDS TO RELATIVE VELOCITY OF REMOTE OBJECT
30		CRYSTAL OR GEM EXAMINATION
31		. Axes determination
32		MATERIAL STRAIN ANALYSIS
33		. With polarized light
34		. . Attached detector
35		. . Sheet material
35.5		. By light interference detector (e.g., interferometer)
36		WITH SAMPLE PREPARATION
37		. Condensation nuclei detector
38		. Depositing particles on optical surface
39		BLOOD ANALYSIS
40		. Hemoglobin concentration
41		. . Oximeters
42		. . Standards
43		OPTICAL PYROMETERS
44		. With sample engaging rod or tube
45		. Plural color responsive
46		. With incandescent standard
47		. . Automatic intensity control
48		. . Modulating (e.g., flicker beam)
49		. . Telescopic
50		. . . Current control
51		INFRARED AND ULTRAVIOLET
52		EGG CANDLING
53		. Photoelectric
54		. With counting, marking, or weighing
55		. With egg transfer
56		. . With egg turning or jarring
57		. . . Endless conveyor
58		. . Endless conveyor
59		. . Manual transfer
60		. . . With light shading chamber
61		. . . Portable receptacles
62		. With light shading chamber
63		. . Hood type
64		. With light box
65		. . With egg turning or jarring
66		. . With particular illumination means
67		. . . With particular electrical switching
68		. Lamp attachments
69		CUTTING BLADE SHARPNESS
70		OIL TESTING (E.G., CONTAMINATION)
71		DOCUMENT PATTERN ANALYSIS OR VERIFICATION
72		WITH PLURAL DIVERSE TEST OR ART
73		PLURAL TEST
73.1		FOR OPTICAL FIBER OR WAVEGUIDE INSPECTION
300		BY DISPERSED LIGHT SPECTROSCOPY
301		. With Raman type light scattering
302		. For spectrographic (i.e., photographic) investigation
303		. . With spectral analysis
304		. . With sectored disc
305		. . With diffraction grating
306		. With internal standard comparison
307		. With background radiation comparison
308		. With synchronized spectrum repetitive scanning (e.g., cathode-ray readout)
309		. . Using plural beams
310		. With aperture mask
311		. With sample excitation (e.g., burning)
312		. . By electrical resistance heating (e.g., graphite tube)
313		. . By arc or spark
314		. . . Including sputtering
315		. . By flame
316		. . By high frequency field (e.g., plasma discharge)
317		. . By light
318		. . . Monochromatic (e.g., laser)
319		. Utilizing a spectrophotometer (i.e., plural beam)
320		. . Having plural wavelengths
321		. . Having servo equalization
322		. . . With polarized light beams
323		. . Having beam modulation
324		. . . With plural dispersion
325		. . . Prior to testing
326		. Utilizing a spectrometer
327		. . Having light polarizing means
328		. . Having diffraction grating means
329		. . . Including servo slit adjustment means
330		. . Having optical gating means
331		. With monochromator structure
332		. . Having adjustable color or bandwidth
333		. . . In a double monochromator
334		. . . With diffraction grating means
335		FOR SIZE OF PARTICLES
336		. By particle light scattering
337		BY PARTICLE LIGHT SCATTERING
338		. With photocell detection
339		. . At right angles to the light beam (e.g., nephelometer)
340		. . At variable angle to the light beam
341		. . For light comparison means
342		. . Of back-scattered light
343		. . Using plural photocells
344		BY ELECTROPHORESIS
450		BY LIGHT INTERFERENCE (E.G., INTERFEROMETER)
451		. Spectroscopy
452		. . Having particular linear mirror drive or configuration
453		. . Polarization
454		. . Fabry-Perot type or Etalon Type
455		. . Having a rotating, pendulous, or wedge scanning element
456		. . Imaging
457		. Holography
458		. . For optical configuration
459		. Rotation rate (e.g., ring laser gyros)
460		. . By fiber or waveguide interferometer (e.g., Sagnac effect)
461		. . . Resonant loop
462		. . . Multi-axis (X-Y-Z) having multiplexing
463		. . . Multiple harmonic output
464		. . . Having null feedback loop
465		. . . Fiber coil winding
466		. . . Having m x n loop coupler where (m is greater than 2) and (n is greater than or equal to 2) (e.g., passive bias)
467		. . Four frequency, multi-oscillator, non-planar cavity
468		. . Cavity output beam combiner
469		. . Cavity mirror details
470		. . Passive cavity (laser source outside cavity)
471		. . Multi-axis cavity
472		. . Lock-in prevention
473		. . . Path length control (PLC)
474		. . . Having dither signal removal from output
475		. . . Having dither signal control
476		. . . By dithering (suspensions, drives, flexures)
477		. Using fiber or waveguide interferometer
478		. . Multiplexed sensor array
479		. . Having a short coherence length source
480		. . Resonant cavity
481		. . Refraction indexing
482		. . For distance or displacement measurement
483		. . Plural counter-propagating beams (e.g., non-motion Sagnac device)
484		. Having light beams of different frequencies (e.g., heterodyning)
485		. . For dimensional measurement (e.g., thickness gap, alignment, profile)
486		. . . Displacement or distance
487		. . . . Polarization
488		. . . . . Having wavefront division (e.g., by diffraction)
489		. . . Contour or profile
490		. . . Alignment
491		. Having polarization
492		. . For dimensional measurement
493		. . . Displacement or distance
494		. . . . Having wavefront division (e.g., by diffraction)
495		. . . Contour or profile
496		. For dimensional measurement
497		. . Having short coherence length source
498		. . Displacement or distance
499		. . . Having wavefront division (e.g., by diffraction)
500		. . . X-Y and/or Z table
501		. . . Of probe head (e.g., atomic force microscope)
502		. . . Surface displacement due to acoustic wave propagation)
503		. . Thickness
504		. . . Refraction from surfaces of different refractive index
505		. . Gap
506		. . . Fabry-Perot type
507		. . . Between slider/disc (e.g., flying height)
508		. . For orientation or alignment
509		. . . Between mask and wafer
510		. . . Tilt
511		. . Contour or profile
512		. . . By wavefront detection
513		. . . . Of highly reflective surface (e.g., mirror)
514		. . . . . Planar surface
515		. . . . Of transmission (e.g., lens)
516		. . . Step height (differential, between points)
517		. For refractive indexing
518		. . Having Schlieren effect
519		. Having partially reflecting plates in series (e.g., Fabry-Perot type)
520		. Having shearing
521		. Having wavefront division (by diffraction)
364		BY POLARIZED LIGHT EXAMINATION
365		. With birefringent element
366		. With polariscopes
367		. . Including polarimeters
368		. . . With electro-optical light rotation
369		. Of surface reflection
370		. With light attenuation
371		FOR FLATNESS
121		LAMP BEAM DIRECTION OR PATTERN
122		. With lamp focusing
123		FOCAL POSITION OF LIGHT SOURCE
124		LENS OR REFLECTIVE IMAGE FORMER TESTING
124.5		. For optical transfer function
125		. Focal length measuring
126		. . Deflecting or interrupting optical path
127		. Optical center, cylinder axis, or prism measuring or determining
128		REFRACTION TESTING (E.G., REFRACTOMETERS)
129		. Schlieren effect
130		. Differential
131		. . With servo controlled optical member
132		. . . Reflective optical member
133		. Refractive rod engages specimen
134		. Prism forming fluid specimen container
135		. Prism engaging specimen
136		. . Internally reflecting prism
137		. . Plural prisms
138		ANGLE MEASURING OR ANGULAR AXIAL ALIGNMENT
139		. Plural scales or different portions of same scale simultaneously observable
139.01		. Star/Sun/Satellite position indication with photodetection
139.02		. . With reticle or slot
139.03		. Relative attitude indication along 3 axes with photodetection
139.04		. Automatic following or aligning while indicating measurement
139.05		. . With optical elements moving relative to fixed housing to follow or align
139.06		. . With optical housing moving to follow or align
139.07		. . With photodetection of reflected beam angle with respect to a unidirectional source beam
139.08		. . . With source beam moving to follow or align
139.09		. Wheel alignment with photodetection
139.1		. Photodetection of inclination from level or vertical
140		. Apex of angle at observing or detecting station
141.1		. . With photodetection of reflected beam angle with respect to a unidirectional source beam
141.2		. . With photodetection
141.3		. . . With unidirectional or planar source beam directed at the photodetecting station
141.4		. . . With optical scanning of light beam or detector
141.5		. . . With at least 2-dimensional sensitivity
142		. . Scale and remote point simultaneously observable
143		. . . Artificial reference
144		. . With plural images
145		. . . Lines of sight relatively adjustable with two degrees of freedom
146		. . . Two or more lines of sight deflected
147		. . Measurement in two planes (e.g., azimuth and elevation; hour angle and declination)
148		. . Artificial reference
149		. . . Gyroscope or pendulum stabilized optical element
150		. Sides of angle or axes being aligned transverse to optical axis (e.g., drift meter)
151		. . With light pulsing or interrupting means
152.1		. With photodetection remote from measured angle
152.2		. . With reflection of a unidirectional source beam from a planar or nonretroreflective surface
152.3		. . With reflection of a unidirectional source beam from a retroreflector
153		. Alignment of axes nominally coaxial
154		. With screen
155		. . Wheel alignment
372		BY MENSURATION
373		. Of article displacement
374		. . Including moire' fringe generation
375		. Of position
376		. Of contour or profile
377		. . With curve readers
378		. Of cavities
379		. Of area or volume
380		. . By scanning
381		. Of thickness
382		. . Of light permeable material
383		. Of length
384		. Of width or diameter
385		. . Of moving object
386		. . . By scanning or light interruption
387		. . By scanning or light interruption
388		BY CONFIGURATION COMPARISON
389		. With photosensitive film or plate
390		. With two images of single article compared
391		. With projection on viewing screen
392		. . For comparison with master or desired configuration
393		. . . Having master or desired configuration projection
394		. With comparison to master, desired shape, or reference voltage
395		. With relatively movable optical grids
396		. With scale or optical grid displaced relative to remote fiducial mark
397		. With object being compared and scale superimposed
398		. With object being compared and light beam moved relative to each other (e.g., scanning)
399		BY ALIGNMENT IN LATERAL DIRECTION
400		. With light detector (e.g., photocell)
401		. With registration indicia (e.g., scale)
402		BY SHADE OR COLOR
403		. With merging colors or patterns (e.g., Maxwell disc)
404		. Photography
405		. Tristimulus examination
406		. Trichromatic examination
407		. With sample responsive to plural colors applied simultaneously
408		. With sequential comparison of sample and standard
409		. Fluid color transmission examination
410		. . Of flowing liquids
411		. . . With plural light detectors (e.g., photocells)
412		. . With ionic determination
413		. . With variable light path length
414		. . With color transmitting filter
415		. . . Including liquid filter comparison
416		. With color transmitting filter
417		. . Included with sample excitation
418		. . Including rotating sequential filters
419		. . Including multicolor filters
420		. . Included with colored light sources
421		. With reflective multicolor chart or standard
422		. . Plate
423		. . . Disk
424		. . Drum or endless tape
425		. With color determination by light intensity comparison
426		BY INSPECTION WITH AGITATION OR ROTATION
427		. Of container contents
428		. Of containers
429		BY MONITORING OF WEBS OR THREAD
430		. For flaws or imperfections
431		. . Including transverse scanning
432		FOR LIGHT TRANSMISSION OR ABSORPTION
433		. By comparison
434		. . Photoelectric (e.g., sequential viewing)
435		. . . With plural detectors (e.g., simultaneous viewing)
436		. Of fluent material
437		. . Gas
438		. . . Exhaust, dust or smoke
439		. . . . Contained
440		. . With significant sample holder or supply
441		. . Having particles suspended in liquid
442		. . . With light detector
443		. Of photographic film
444		. . With scanning, sweeping, or moving detector over film
445		OF LIGHT REFLECTION (E.G., GLASS)
446		. With diffusion
447		. With modulation (e.g., flicker beam)
448		. By comparison
213		PHOTOMETERS
214		. Pupillary
215		. Integrating
216		. Heat absorbing (e.g., radiometers)
217		. Modulating (e.g., flicker beam)
218		. Photoelectric
219		. . Simultaneous sighting and reading measurement
220		. . Multiple housings
221		. . Responsive to incident or back lighting
222		. . Plural detectors
223		. . Logarithmic
224		. . Multisensitivity range
225		. . With predetector light modifier (e.g., diaphragm)
226		. . Detector and indicator electrical coupling (e.g., amplifying or attenuating)
227		. . With particular indicator
228		. . . Movable scale (e.g., calibrating)
229		. Comparison
230		. . With light standard
231		. . . Variable incandescent standard
232		. . . Standard movable
233		. With variable light aperture size
234		. Light absorbing
235		. . Absorber continuously variable (e.g., wedge)
236		. Integrating spheres
237.1		INSPECTION OF FLAWS OR IMPURITIES
238.1		. Textile inspection
238.2		. . Elongated textile product (e.g., thread, yarn, etc.)
238.3		. . Detection of foreign material (e.g., trash, splinters, contaminants, etc.)
239.1		. Transparent or translucent material
239.2		. . Optical element (e.g., contact lens, prism, filter, lens, etc.)
239.3		. . Patterned surface
239.4		. . Containers (e.g., bottles)
239.5		. . . Detection of foreign matter on or in container
239.6		. . . Of container contents
239.7		. . Surface condition
239.8		. . . Detection of an object or particle on surface
240.1		. Containers or enclosures (e.g., packages, cans, etc.)
241.1		. Bore inspection (e.g., borescopes, intrascope, etc.)
241.2		. . Firearm bore inspection
241.3		. . With adjustable head
241.4		. . Flexible
241.5		. . Specific construction of distal end
241.6		. . Having guiding means
237.2		. Surface condition
237.3		. . Detection of object or particle on surface
237.4		. . . On patterned or topographical surface (e.g., wafer, mask, circuit board)
237.5		. . On patterned or topographical surface (e.g., wafer, mask, circuit board)
237.6		. Having predetermined light transmission regions (e.g., holes, aperture, multiple material articles)
242.1		THREAD COUNTING
243.1		STANDARD
243.2		. For fluid suspended particles
243.3		. Flying height testers
243.4		. Surface standard
243.5		. . Color
243.6		. . Foreign object
243.7		. . Texture
243.8		. . Light intensity
244		SAMPLE, SPECIMEN, OR STANDARD HOLDER OR SUPPORT (E.G., PLATES OR SLIDES)
245		. Cotton graders
246		. Fluid containers (e.g., cells or cuvettes)
247		FIDUCIAL INSTRUMENTS
248		. Artificial reference
249		. . Liquid surface (e.g., bubble level)
250		. . Pendular suspension of optical element or reticle
251		. Reticle lies outside viewing path
252		. . Reticle image transversely adjustable relative to optical axis
253		. Deflection of line of sight
254		. . Two or more deflections
255		. . By reflection
256		MISCELLANEOUS
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		CROSS REFERENCE ART COLLECTIONS
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900		INTERFEROMETERS (GO1B 9/02)
901		. Involving fiber optics or integrated optics (GO1B 9/02F)
902		. Involving diffraction gratings (GO1B 9/02G)
903		. Using holographic techniques (GO1B 9/021)
904		MEASURING MICROSCOPES (GO1B 9/04)
905		MEASURING TELESCOPES (GO1B 9/06)
906		OPTICAL PROJECTION COMPARATORS, E.G., FOR PROFILE (GO1B 9/08)
907		GONIOMETERS (GO1B 9/10)
908		MEASURING LENGTH, WIDTH, OR THICKNESS (GO1B 11/02)
909		. By means of tv-camera scanning (GO1B 11/02B)
910		. By means of diode-array scanning (GO1B 11/02C)
911		MEASURING THE DEFORMATION IN A SOLID, E.G., OPTICAL STRAIN GAUGE (GO1B 11/16)
912		MEASURING ANGLES (GO1C 1/00)
913		. Theodolites (GO1C 1/02)
914		. . Combined with cameras (GO1C 1/04)
915		. Sextants (GO1C 1/08)
916		ALTIMETERS FOR AIRCRAFT (GO1C 5/00A)
917		MEASURING INCLINATION, E.G., BY CLINOMETERS, BY LEVELS (GO1C 9/00)
918		PHOTOGRAMMETRY; PHOTOGRAPHIC SURVEYING (GO1C 11/00)
919		. Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g., controlling overlapping of pictures (GO1C 11/02)
920		. . By scanning the object (GO1C 11/02A)
921		. Interpretation of pictures (GO1C 11/04)
922		PHOTOMETRY, E.G., PHOTOGRAPHIC EXPOSURE METER (GO1J 11/04)
923		RADIATION PYROMETRY (GOLJ 5/00)
924		MEASURING VELOCITY OF LIGHT (GOLJ 7/00)
925		MEASURING OPTICAL PHASE DIFFERENCE: MEASURING OPTICAL WAVELENGTH (GO1J 9/00)
926		MEASURING THE CHARACTERISTICS OF INDIVIDUAL OPTICAL PULSES OR OF OPTICAL PULSE TRAINS (GO1J 11/00)
927		MEASURING VARIATIONS OF OPTICAL PROPERTIES OF MATERIAL WHEN IT IS STRESSED, E.G., BY PHOTOELASTIC STRESS ANALYSIS USING INFRA-RED, VISIBLE LIGHT, ULTRA-VIOLET (GO1L 1/24)
928		INVESTIGATING OR ANALYZING MATERIALS BY THE USE OF OPTICAL MEANS, I.E., USING INFRA-RED, VISIBLE, OR ULTRA-VIOLET LIGHT (GO1N 21/00)
929		. Arrangements, or apparatus for facilitating the optical investigation (GO1N 21/01)
930		. . Cuvette constructions (GO1N 21/03)
931		. Systems in which incident light is modified in accordance with the properties of material investigated (GO1N 21/17)
932		. . With opto-acoustic detection, e.g., for gases or analyzing solids (GO1N 21/17B)
933		. . With calorimetric detection, e.g., with thermal lens detection (GO1N 21/17C)
934		. . With modulation of one or more physical properties of the sample during optical investigation, e.g., Electra reflectance (GO1N 21/17M)
935		. . Dichroism (GO1N 21/19)
936		. . Polarization-affecting properties (GO1N 21/21)
937		. . . Ellipsometry (GO1N 21/21B)
938		. . . Bi-refringence (GO1N 21/23)
939		. . Color; spectral properties, i,e., comparison of effect of material on the light at two or more different wavelengths or wavelength bands (GO1N 21/25)
940		. . . Colorimeters (GO1N 21/25B)
941		. . . . For batch operation, i.e., multi-sample apparatus (GO1N 21/25B2)
942		. . . Arrangements using two alternating lights and one detector (GO1N 21/25D)
943		. . . Using photo-electric detection (GO1N 21/27)
944		. . . . For following a reaction, e.g., for determining photometrically a reaction rate (GO1N 21/27C)
945		. . . Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g., atomic absorption spectrometry (GO1N 21/31)
946		. . Holographic interferometry (GO1N 21/45B)
947		. . Scattering, i.e., diffuse reflection (GO1N 21/47F)
948		. Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light (GO1N 21/62)
949		. . Optically excited (GO1N 21/63)
950		. . . Using photolysis and investigating photolyzed fragments (GO1N 21/63C)
951		. . . Florescence; Phosphorescence (GO1N 21/64)
952		. . . Raman scattering (GO1N 21/65)
953		. Probe photometers (GO1N 21/85B)
954		. Scan or image signal processing arrangements specially adapted for investigating the presence of flaws or contaminates, e.g., for scan signal adjustments, for detecting different kinds of defects, for compensating for structures (GO1N 21/88)
955		MEASURING LINEAR OR ANGULAR SPEED UTILIZING DEVICES CHARACTERIZED BY THE USE OF OPTICAL MEANS, E.G., USING INFRA-RED, VISIBLE, OR ULTRA-VIOLET LIGHT (GO1P 3/36)
956		. Using a ring laser (GO1P 3/36B)
957		. Using diffraction of light (GO1P 3/36C)
958		. Using photographic means (GO1P 3/38)
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		FOREIGN ART COLLECTIONS
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		Any foreign patents or non-patent literature from subclasses that have been classified have been transferred directly to FOR Collection listed below. These collections contain ONLY foreign patents or non-patent literature. The parenthetical references in the Collection titles refer to the abolished subclasses from which these Collections were derived
FOR 100		INSPECTION FOR FLAWS OR IMPERFECTIONS (356/237)
FOR 101		. Cloth or thread inspection (356/238)
FOR 102		. Passing light through a transparent or translucent article (356/239)
FOR 103		. . Containers (e.g., bottles) or contents (356/240)
FOR 104		. Bore inspection (e.g., borescopes) (356/241)
FOR 105		THREAD COUNTING (356/242)
FOR 106		STANDARDS (356/243)
FOR 107		BY LIGHT INTERFERENCE (E.G., INTERFEROMETERS) (356/345)
FOR 108		. Spectroscopy (356/346)
FOR 109		. Holography (356/347)
FOR 110		. . For optical configuration (356/348)
FOR 111		. With light beams of different frequency (e.g., heterodyning) (356/349)
FOR 112		. . For rotation rate (e.g., ring laser) (356/350)
FOR 113		. With polarization (356/351)
FOR 114		. With partially reflecting plates in series (e.g., Fabry-Perot type) (356/352)
FOR 115		. With shearing (356/353)
FOR 116		. With wavefront division (e.g., by diffraction) (356/354)
FOR 117		. . For dimensional measurement (e.g., thickness) (356/355)
FOR 118		. . . Of displacement or distance (356/356)
FOR 119		. For dimensional measurement (e.g., thickness) (356/357)
FOR 120		. . Of displacement or distance (356/358)
FOR 121		. For optical configuration (356/359)
FOR 122		. . With two light beams (e.g., Twyman-Green) (356/360)
FOR 123		. For refractive indexing (356/361)
FOR 124		. . With Schlieren effect (356/362)
FOR 125		. For orientation and alignment (356/363)

Information Products Division -- Contacts

Questions regarding this report should be directed to:

U.S. Patent and Trademark Office
Information Products Division
PK3- Suite 441
Washington, DC 20231

tel: (703) 306-2600
FAX: (703) 306-2737
email: oeip@uspto.gov

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Last Modified: 6 October 2000