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Class   356	OPTICS: MEASURING AND TESTING
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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

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

600

SURFACE ROUGHNESS

601

SHAPE OR SURFACE CONFIGURATION

602

Triangulation

603

Projection of structured light pattern

604

Pattern is series of non-intersecting lines

605

Moire

606

Line of light projected

607

Scan

608

Scan

609

By focus detection

610

By projection of coded pattern

611

By stereo

612

By specular reflection

613

Silhouette

614

POSITION OR DISPLACEMENT

615

Position transverse to viewing axis

616

Having scale or grid

617

Coded scale

618

Moire

619

Quadrature detection

620

Special mark or target on object

621

Occulting a projected light beam

622

Position of detected arrangement relative to projected beam

623

Triangulation

624

Focus

625

DIMENSION

626

Cavities

627

Volume

628

Area

629

Light scanning

630

Thickness

631

By triangulation

632

Of light permeable material

634

Length

635

Width or diameter

636

Line width

637

Web

638

Shadow or beam blocking

639

Scanning

640

Single beam scans entire width or diameter

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

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)

FOR101

Cloth or thread inspection (356/238)

FOR102

Passing light through a transparent or translucent article (356/239)

FOR103

Containers (e.g., bottles) or contents (356/240)

FOR104

Bore inspection (e.g., borescopes) (356/241)

FOR108

Spectroscopy (356/346)

FOR109

Holography (356/347)

FOR110

For optical configuration (356/348)

FOR111

With light beams of different frequency (e.g., heterodyning) (356/349)

FOR112

For rotation rate (e.g., ring laser) (356/350)

FOR113

With polarization (356/351)

FOR114

With partially reflecting plates in series (e.g., Fabry-Perot type) (356/352)

FOR115

With shearing (356/353)

FOR116

With wavefront division (e.g., by diffraction) (356/354)

FOR117

For dimensional measurement (e.g., thickness) (356/355)

FOR118

Of displacement or distance (356/356)

FOR119

For dimensional measurement (e.g., thickness) (356/357)

FOR120

Of displacement or distance (356/358)

FOR121

For optical configuration (356/359)

FOR122

With two light beams (e.g., Twyman-Green) (356/360)

FOR123

For refractive indexing (356/361)

FOR124

With Schlieren effect (356/362)

FOR125

For orientation and alignment (356/363)

FOR128

Of article displacement (356/373)

FOR129

Including moire' fringe (356/374)

FOR130

Of position (356/375)

FOR131

Of contour or profile (356/376)

FOR132

With curve readers (356/377)

FOR133

Of cavities (356/378)

FOR134

Of area or volume (356/379)

FOR135

By scanning (356/380)

FOR136

Of thickness (356/381)

FOR137

Of light permeable material (356/382)

FOR138

Of length (356/383)

FOR139

Of width or diameter (356/384)

FOR140

Of moving object (356/385)

FOR141

By scanning or light interruption (356/386)

FOR142

By scanning or light interruption (356/387)

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