US3770353A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical sensor
Assignee: United States Department of the Navy
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Filing: 1971-08-25
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Granted: 1973-11-06
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Expires: 1991-08-25
Abstract
Abstract This invention is directed to an electro-optical sensor which can accurately measure small displacements. The sensor utilizes a modulated light source and has a shutter whose displacement controls the light which impinges on a pair of phototransistors. The phototransistors are connected to a transformer and their output is a measure of the displacement of the shutter.
Inventors
- 👤 C Brown
- 👤 F Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:01
CPC Classifications
G; G01; G01D; G01D5/00; G01D5/26; G01D5/32; G01D5/34; G01D5/347; G01D5/34707; G01D5/34715; G01D5/34723
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
201 words
An electro-optical sensor for sensing the displacement of a transducer comprising: a lighT source; an alternating current supply connected across said light source; an apertured shutter having first and second apertures for attachment to a transducer to be displaced thereby and operable to control the light received by a photoelectric detector; a photoelectric detector mounted adjacent to the apertured shutter on one side thereof, said photoelectric detector utilizing two phototransistors, one of said phototransistors being mounted adjacent to said first aperture in said shutter and the other phototransistor being mounted adjacent to said second aperture in said shutter, said photoelectric detector being operable to receive light from said source to convert the received light to an electric signal; output means providing an electrical output which is proportional to the light received by said detector, said output means comprising a centertapped transformer connected to the collectors of said two phototransistors, a direct current source connected to said center tap and a pair of resistors connected between the emitters of said phototransistors and ground; and a pair of light pipes each having one end mounted adjacent to said light source and one end adjacent to said first or second apertures in said shutter.
Claim 2
Dependent Claim
201 words
An electro-optical sensor for sensing the displacement of a transducer comprising: a lighT source; an alternating current supply connected across said light source; an apertured shutter having first and second apertures for attachment to a transducer to be displaced thereby and operable to control the light received by a photoelectric detector; a photoelectric detector mounted adjacent to the apertured shutter on one side thereof, said photoelectric detector utilizing two phototransistors, one of said phototransistors being mounted adjacent to said first aperture in said shutter and the other phototransistor being mounted adjacent to said second aperture in said shutter, said photoelectric detector being operable to receive light from said source to convert the received light to an electric signal; output means providing an electrical output which is proportional to the light received by said detector, said output means comprising a centertapped transformer connected to the collectors of said two phototransistors, a direct current source connected to said center tap and a pair of resistors connected between the emitters of said phototransistors and ground; and a pair of light pipes each having one end mounted adjacent to said light source and one end adjacent to said first or second apertures in said shutter.
Claim 3
Dependent Claim
23 words
An electro-optical sensor for sensing the displacement of a transducer as in claim 1 wherein said light source is a gallium arsenide diode.
Claim 4
Dependent Claim
21 words
An electro-optical sensor for sensing the displacement of a transducer as in claim 1 wherein said light source is a lamp.
Claim 5
Dependent Claim
96 words
A photoelectric sensor comprising: means for sensing mechanical movement and for providing a physical response to such movement; means for illuminating said movement sensing means with light; means for receiving said light in an amount that varies with the magnitude of the physical response of said movement sensing means, said light receiving means comprising one phototransistor; means for providing an electrical output signal which is proportional to the amount of light received by said light receiving means and operable to prevent an output signal from being generated in response to a shorting failure of said phototransistor.
Claim 6
Dependent Claim
96 words
A photoelectric sensor comprising: means for sensing mechanical movement and for providing a physical response to such movement; means for illuminating said movement sensing means with light; means for receiving said light in an amount that varies with the magnitude of the physical response of said movement sensing means, said light receiving means comprising one phototransistor; means for providing an electrical output signal which is proportional to the amount of light received by said light receiving means and operable to prevent an output signal from being generated in response to a shorting failure of said phototransistor.
Claim 7
Dependent Claim
34 words
A photoelectric sensor as in claim 4, wherein the movement sensing means comprises a transducer which senses mechanical movement and an apertured shutter which is displaced by said transducer to produce said physical response.
Claim 8
Dependent Claim
62 words
A photoelectric sensor as in claim 4, wherein: said light receiving means comprises a plurality of phototransistors; said movement sensing means comprises a shutter having a plurality of apertures corresponding to the number of phototransistors; and said light receiving means and said apertured shutter are arranged so that one of said phototransistors is mounted adjacent to its corresponding aperture in said shutter.
Claim 9
Dependent Claim
16 words
A photoelectric sensor as in claim 4 wherein said illuminating means is a modulated light source.
Claim 10
Dependent Claim
51 words
A photoelectric sensor as in claim 7 wherein: said output means comprises a transformer which provides a. an electrical output signal when said phototransistor is operative and receives said modulated light; and b. no electrical output when said phototransistor is opened or shorted, even though said phototransistor receives said modulated light.
Claim 11
Dependent Claim
70 words
A photoelectric sensor as in claim 7 wherein: said light receiving means comprises a plurality of phototransistors; and said output comprises a transformer which provides a. an electrical output signal from any of said plurality of phototransistors that are operative and receive said modulated light; and b. no electrical output from any of said plurality of phototransistors that are opened or shorted, even though such phototransistor receives said modulated light.
Claim 12
Dependent Claim
80 words
A photoelectric sensor as in claim 7 wherein: said light receiving means comprises a second phototransistor; said output means comprises a direct current source connecteD to the center tap of a transformer; the collectors of both of said phototransistors are connected to the ends of the center tapped transformer and their emitters are connected to ground through a pair of resistors; said transformer prevents the generation of a direct current signal in the output when either of said phototransistor shorts.
References Cited (Backward Citations)
US3369445A
Cited
US3502894A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-05 | 1977-05-07 | 1977-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-05 | 1981-05-07 | 1981-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-05 | 1985-05-07 | 1985-11-06 | $7700.00 | Window Closed / Lapsed |