US3774039A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoelectric apparatus for detecting light reflected from an object
Assignee: SCIENT TECHN Inc
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Filing: 1973-03-05
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Granted: 1973-11-20
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Expires: 1993-03-05
Abstract
Abstract A photoelectric apparatus including a light emitting diode mounted at the center of a lens for emitting light with the lens serving to focus emitted light reflected from objects upon a photodetector axially disposed behind the diode, and an electrical system for cyclically energizing said light emitting diode at a predetermined frequency and amplifier means tuned to said frequency and applying its amplified output signal to a circuit which develops a control signal when the input signal exceeds a predetermined adjustable value.
Inventors
- 👤 E Price
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:47
CPC Classifications
G; G01; G01V; G01V8/00; G01V8/10; G01V8/12; G01N; G01N21/00; G01N21/17; G01N21/55; G08; G08B; G08B13/00; G08B13/18; G08B13/181; G08B13/187
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
133 words
A photoelectric system including a lens, a photodetector mounted coaxially behind said lens, a light emitting diode mounted axially in said lens and extending to the front of said lens to emit light away from the lens, said lens serving to receive emitted light reflected from objects in front of said lens to focus the light on said photodetector, means for alternately energizing and extinguishing said light emitting diode at a predetermined frequency, means for receiving the output of the photodetector, said last named means tuned to said predetermined frequency to provide an output only when pulsating light at said predetermined frequency is reflected and received, and a level detector for receiving the output from the means tuned to said predetermined frequency and providing output pulses when the input exceeds a predetermined level.
Claim 2
Dependent Claim
133 words
A photoelectric system including a lens, a photodetector mounted coaxially behind said lens, a light emitting diode mounted axially in said lens and extending to the front of said lens to emit light away from the lens, said lens serving to receive emitted light reflected from objects in front of said lens to focus the light on said photodetector, means for alternately energizing and extinguishing said light emitting diode at a predetermined frequency, means for receiving the output of the photodetector, said last named means tuned to said predetermined frequency to provide an output only when pulsating light at said predetermined frequency is reflected and received, and a level detector for receiving the output from the means tuned to said predetermined frequency and providing output pulses when the input exceeds a predetermined level.
Claim 3
Dependent Claim
52 words
A photoelectric system as in claim 1 wherein said level detector includes means for adjusting the level of input signal at which an output signal is generated, together with an integrator for receiving said level detector output and providing a DC output for indicating presence of objects in front of said lens.
Claim 4
Dependent Claim
46 words
A photoelectric system as in claim 1 including a reflector spaced from said light emitting diode to reflect light into said lens together with means for receiving the output of said level detector, said last named means providing an indication when the reflected light is interrupted.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-19 | 1977-05-21 | 1977-11-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-19 | 1981-05-21 | 1981-11-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-19 | 1985-05-21 | 1985-11-20 | $7700.00 | Window Closed / Lapsed |