Patent EP0110856A1 successfully refreshed from Google Patents.
US3679307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Non-contacting optical probe
Assignee: ATI Inc Indiana
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Filing: 1970-02-19
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Granted: 1972-07-25
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Expires: 1990-02-19
Abstract
Abstract A distance measuring device for deriving contour information without contacting the surface being measured and without the use of internal moving parts. The device utilizes an optical system and geometric triangulation techniques to develop electrical output signals which may be used to drive readout displays and numerically controlled machine tools or the like. One embodiment of the device includes a specially configured photo detector which compensates for certain ranging errors encountered in previously known devices. Data processing electronics are provided for a variety of operations and applications. A particular feedback light control system is employed to compensate for variations in reflected light levels.
Inventors
- 👤 Robert Martin Zoot
- 👤 James Leo Scieszinski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:01
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/24
Claims Analysis
Total Claims: 47
Claim 1
Independent Claim
130 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for directing light at a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, said photodetector being divided into two pairs of distinct active areas with each active area developing an electrical signal in accordance with the portion of the reflected light incident thereon; electrical circuitry connected to said photodetector for developing comparison signals from the individual active area electrical signals; means for deriving gradient signals from each pair of said pairs of active areas; and means for processing said derived signals and said comparison signals to provide an output signal indicative of the distance from the photodetector to the target.
Claim 2
Dependent Claim
130 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for directing light at a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, said photodetector being divided into two pairs of distinct active areas with each active area developing an electrical signal in accordance with the portion of the reflected light incident thereon; electrical circuitry connected to said photodetector for developing comparison signals from the individual active area electrical signals; means for deriving gradient signals from each pair of said pairs of active areas; and means for processing said derived signals and said comparison signals to provide an output signal indicative of the distance from the photodetector to the target.
Claim 3
Dependent Claim
31 words
A system in accordance with claim 1 further including an indicator responsive to said output signal and calibrated in units of linear measurement for directly indicating said distance in said units.
Claim 4
Dependent Claim
153 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for directing light at a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, said photodetector having first and second pairs of separate active areas, the areas of each pair being substantially equal in extent and symmetrically located thereon, each active area developing an electrical signal in accordance with the portion of reflected light incident thereon; means for directing the reflected light in a beam to be substantially equally shared by the first pair of active areas at a predetermined reference distance from the target; electrical circuitry connected to said photodetector for developing comparison signals from the individual active area electrical signals; and means for processing said comparison signals to provide an output signal indicative of the distance from the photodetector to the target.
Claim 5
Dependent Claim
153 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for directing light at a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, said photodetector having first and second pairs of separate active areas, the areas of each pair being substantially equal in extent and symmetrically located thereon, each active area developing an electrical signal in accordance with the portion of reflected light incident thereon; means for directing the reflected light in a beam to be substantially equally shared by the first pair of active areas at a predetermined reference distance from the target; electrical circuitry connected to said photodetector for developing comparison signals from the individual active area electrical signals; and means for processing said comparison signals to provide an output signal indicative of the distance from the photodetector to the target.
Claim 6
Dependent Claim
45 words
A system in accordance with claim 43 wherein said light directing means is positioned to direct a reflected light beam off the center of said first pair of active areas for distances between the cell and the target which are different fRom said reference distance.
Claim 7
Dependent Claim
55 words
A system in accordance with claim 4 wherein said second pair of active areas is positioned within the area encompassed by said first pair so as to receive reflected light from the target incident throughout the extent of the active areas of said second pair for all operating positions of said photodetector and light source.
Claim 8
Dependent Claim
64 words
A system in accordance with claim 43 wherein said electrical circuitry comprises comparison means connected to receive the signals from the respective pairs of active areas of the photodetector and provide a first comparison signal which is the sum of electrical signals from one pair and a second comparison signal which is the difference between the signals from said one pair of active areas.
Claim 9
Dependent Claim
35 words
A system in accordance with claim 6 wherein said processing means includes a signal dividing circuit for developing an output signal which is equal to the second comparison signal divided by the first comparison signal.
Claim 10
Dependent Claim
46 words
A system in accordance with claim 6 further including additional comparison means for developing a difference signal from the signals received from the other pair of active areas and modifying the first comparison signal in order to compensate for distance errors in said first comparison signal.
Claim 11
Dependent Claim
33 words
A system in accordance with claim 6 wherein said processing means includes automatic gain control circuitry for controlling the amplitude of the difference signal in accordance with the amplitude of the sum signal.
Claim 12
Dependent Claim
127 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for directing light at a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, said photodetector being divided into two pairs of distinct active areas with each active area developing an electrical signal in accordance with a portion of the reflected light incident thereon; electrical circuitry connected to said photodetector for developing comparison signals from the individual active area electrical signals; means for processing said comparison signals to provide an output signal indicative of the distance from the photodetector to the target; and means for controlling the intensity of the light source relative to a fixed reference level.
Claim 13
Dependent Claim
127 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for directing light at a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, said photodetector being divided into two pairs of distinct active areas with each active area developing an electrical signal in accordance with a portion of the reflected light incident thereon; electrical circuitry connected to said photodetector for developing comparison signals from the individual active area electrical signals; means for processing said comparison signals to provide an output signal indicative of the distance from the photodetector to the target; and means for controlling the intensity of the light source relative to a fixed reference level.
Claim 14
Dependent Claim
21 words
A system in accordance with claim 44, further including a difference amplifier for driving the light source from the reference level.
Claim 15
Dependent Claim
53 words
A system in accordance with claim 11 further including circuit means for applying the first comparison signal to the input of said difference amplifier to develop a feedback loop for controlling the intensity of the light source in accordance with the sum of the electrical signals developed by one pair of active areas.
Claim 16
Dependent Claim
22 words
A system in accordance with claim 12 further including means for providing a system output signal directly from said other comparison means.
Claim 17
Dependent Claim
22 words
A system in accordance with claim 4 further including traverse means for controlling relative motion between the photodetector and the target object.
Claim 18
Dependent Claim
44 words
A system in accordance with claim 14 wherein said processing means comprises a servomechanism responsive to the difference between the active areas of said detector illuminated by the light beam in order to control the traverse along a selected axis to minimize said difference.
Claim 19
Dependent Claim
46 words
A system in accordance with claim 15 wherein said processing means further includes a signal dividing circuit for driving the servomechanism in accordance with the ratio of the difference divided by the sum of the detector signals. the difference divided by the sum of the detector
Claim 20
Dependent Claim
30 words
A system in accordance with claim 1 further including a deadband signal for indicating when the position of the photodetector is within a preselected threshold range of its true position.
Claim 21
Dependent Claim
37 words
A system in accordance with claim 7 wherein said output signal is approxImately equal to (A1 - A2)/(A1 + A2) where A1 and A2 correspond to the illuminated portions of said first pair of active areas respectively.
Claim 22
Dependent Claim
15 words
A system in accordance with claim 1 wherein said light source comprises an incandescent lamp.
Claim 23
Dependent Claim
15 words
A system in accordance with claim 1 wherein said light source comprises an arc lamp.
Claim 24
Dependent Claim
15 words
A system in accordance with claim 1 wherein said light source comprises a laser beam.
Claim 25
Dependent Claim
18 words
A system in accordance with claim 1 further including means for modulating said light directed at said target.
Claim 26
Dependent Claim
24 words
A system in accordance with claim 22 wherein said modulating means comprises means for varying the intensity of the light from the light source.
Claim 27
Dependent Claim
19 words
A system in accordance with claim 22 wherein said modulating means comprises means for interrupting said light beam periodically.
Claim 28
Dependent Claim
41 words
A system in accordance with claim 43 wherein said second pair of active areas is centrally located within a central aperture within the first pair of active areas, and further including electrical leads connected to each of said separate active areas.
Claim 29
Dependent Claim
127 words
A system in accordance with claim 25 further including individual amplifying means respectively connected to said electrical leads for amplifying each of the signals from the separate active areas individually, a pair of difference amplifiers in parallel, the two difference amplifiers being connected to develop difference signals between separate pairs of the signals from the individual amplifiers, a sum amplifier connected to provide a sum signal corresponding to the sum of one pair of amplifier outputs, another amplifier connected to receive the outputs from the pair of difference amplifiers and to provide a signal which is a comparison of said difference signals, and a processor connected to receive both of said last-mentioned signals and arranged to process the comparison signal under the control of the sum signal.
Claim 30
Dependent Claim
29 words
A system in accordance with claim 1 further including an optical filter positioned between the photodetector and the target for reducing the extent of interfering light at the photodetector.
Claim 31
Dependent Claim
22 words
A system in accordance with claim 27 wherein said optical filter is arranged to block ambient light from reaching the photodetector. photodetector.
Claim 32
Dependent Claim
86 words
A photodetector cell having a plurality of separate active areas for developing separate electrical signals in response to light incident thereon comprising: a base; a first pair of separate active areas symmetrically arrayed on said base and having a central aperture located therein; a second pair of separate active areas symmetrically positioned on said base and located within the aperture in the first pair of active areas; and a plurality of electrical leads, respectively connected to the individual active areas of said first and second pair.
Claim 33
Dependent Claim
86 words
A photodetector cell having a plurality of separate active areas for developing separate electrical signals in response to light incident thereon comprising: a base; a first pair of separate active areas symmetrically arrayed on said base and having a central aperture located therein; a second pair of separate active areas symmetrically positioned on said base and located within the aperture in the first pair of active areas; and a plurality of electrical leads, respectively connected to the individual active areas of said first and second pair.
Claim 34
Dependent Claim
54 words
Apparatus in accordance with claim 29 wherein said first pair of active areas cover a substantially rectangular portion of said base with a substantially circular central aperture and a narrow space extending through said central aperture from side to side of said rectangular portion to separate the two active areas into substantially equal areas.
Claim 35
Dependent Claim
34 words
Apparatus in accordance with claim 30 wherein each of said separate active areas of said first pair is approximately .225 inches across and approximately 0.175 inches wide, excluding the portion of the central area.
Claim 36
Dependent Claim
25 words
Apparatus in accordance with claim 31 wherein said second pair of active areas are each approximately semicircular in shape and approximately 0.015 inches in diameter.
Claim 37
Dependent Claim
20 words
Apparatus in accordance with claim 32 wherein the spacing between the respective pairs of active areas is approximately 0.005 inches.
Claim 38
Dependent Claim
122 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for projecting lighT toward a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, the photodetector being divided into a plurality of active areas with each active area developing an electrical signal in accordance with the portion of the reflected light incident thereon; electrical circuitry connected to the photodetector for developing comparison signals from the individual active area electrical signals; means for controlling the light source from a reference signal level; and means comprising a feedback loop for applying one of said comparison signals to said controlling means to vary the level accordingly.
Claim 39
Dependent Claim
122 words
An optical scanning system for providing distance measurements to a target object being scanned without physical contact therewith comprising: a light source for projecting lighT toward a target; a photodetector for developing electrical signals in accordance with reflected light received from said target, the photodetector being divided into a plurality of active areas with each active area developing an electrical signal in accordance with the portion of the reflected light incident thereon; electrical circuitry connected to the photodetector for developing comparison signals from the individual active area electrical signals; means for controlling the light source from a reference signal level; and means comprising a feedback loop for applying one of said comparison signals to said controlling means to vary the level accordingly.
Claim 40
Dependent Claim
22 words
A system in accordance with claim 34 further including traverse means for controlling relative motion between the photodetector and the target object.
Claim 41
Dependent Claim
37 words
A system in accordance with claim 35 wherein said electrical circuitry further comprises a servomechanism responsive to the difference between the photodetector signals in order to control the traverse along a selected axis to minimize said difference.
Claim 42
Dependent Claim
37 words
A system in accordance with claim 36 wherein said electrical circuitry further includes a signal dividing circuit for driving the servomechanism in accordance with the ratio of the difference divided by the sum of the detector signals.
Claim 43
Dependent Claim
30 words
A system in accordance with claim 34 further including a deadband signal for indicating when the position of the photodetector is within a preselected threshold range of its true position.
Claim 44
Dependent Claim
25 words
A system in accordance with claim 34 wherein said applied signal corresponds to the sum of the signals of the active areas of the photodetector.
Claim 45
Dependent Claim
27 words
A system in accordance with claim 34 further including means for applying another of said comparison signals directly to the system output for utilization by associated apparatus.
Claim 46
Dependent Claim
38 words
A system in accordance with claim 34 further including a divider processor connected to receive said comparison signals and arranged to provide a ratio of one of said comparison signals divided by the other as an output signal.
Claim 47
Dependent Claim
50 words
A system in accordance with claim 41 wherein said output signal is approximately equal to (A1 - A2)/(A1 + A2) where A1 and A2 correspond to the illuminated portions of the separate active areas respectively, and where A1 + A2 is substantially constant within the operating range of the system.
References Cited (Backward Citations)
CA728860A
Cited
US3076378A
Cited
US3076949A
Cited
US3054898A
Cited
US3202820A
Cited
US3481672A
Cited
US3473875A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |