Patent US3837283A successfully refreshed from Google Patents.
US3837283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Active optical fuze
Assignee: United States Department of the Army
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Filing: 1973-08-03
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Granted: 1974-09-24
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Expires: 1993-08-03
Abstract
Abstract An active optical fuze is provided for detecting the transit of a target through a given focal plane and energizing a firing circuit in response to such event. A pair of optical transmitters are alternately pulsed at a known pulse frequency to illuminate two related foci on an approaching target. When the target is not at the focal plane a pair of optical receivers receive light reflected from both foci in-phase. When, however, the target is at the focal plane, the two receivers are illuminated out of phase by only corresponding ones of said foci. In this latter mode of illumination the receivers drive, respectively, the SET and RESET terminals of a bistable multivibrator to thereby generate a firing signal of the same known pulse frequency as that driving the transmitter, which firing signal is then applied to a detecting and firing circuit to energize the latter as the target transits the focal plane.
Inventors
- 👤 Cracken R Mc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:30
CPC Classifications
F; F42; F42C; F42C13/00; F42C13/02; F42C13/023
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
92 words
Optical fuze means providing an output signal in response to the transit of a target through a predetermined focal plane, comprising: optical transmitter means alternately illuminating first and second foci on said target at a predetermined frequency; and optical receiving means selectively responding to reflected illumination from each of said foci to generate a firing signal of said predetermined frequency only when said target transits said focal plane and collectively responding to said reflected illumination from both said foci at substantially all other relative positions of said target and said focal plane.
Claim 2
Dependent Claim
92 words
Optical fuze means providing an output signal in response to the transit of a target through a predetermined focal plane, comprising: optical transmitter means alternately illuminating first and second foci on said target at a predetermined frequency; and optical receiving means selectively responding to reflected illumination from each of said foci to generate a firing signal of said predetermined frequency only when said target transits said focal plane and collectively responding to said reflected illumination from both said foci at substantially all other relative positions of said target and said focal plane.
Claim 3
Dependent Claim
23 words
The invention defined in claim 1, wherein said fuze means further includes detecting and firing circuit means selectively responsive to said firing signal.
Claim 4
Dependent Claim
61 words
The optical fuze means defined in claim 1, wherein said optical transmitter means comprises alternate pulser-driver means driven at said predetermined frequency; first and second light emitting means alternately driven by said pulser-driver means to emit first and second alternating trains of light pulses; and optical means transmitting said first and second pulse trains, respectively, to said first and second foci.
Claim 5
Dependent Claim
25 words
The optical fuze means defined in claim 3, wherein said fuze means further includes detecting and firing circuit means selectively responsive to said firing signal.
Claim 6
Dependent Claim
97 words
The optical fuze means defined in claim 1, wherein said optical receiving means comprises first and second photodetector means responding exclusively to reflected illumination from said first and second foci, respectively, when said target transits said focal plane and collectively to said illumination from said foci at said substantially all other relative positions of said target and focal plane; and bistable circuit means driven between first and second stable states thereof by said first and second photodetector means when said target transits said focal plane and generating said firing signal of said predetermined frequency in response thereto.
Claim 7
Dependent Claim
25 words
The optical fuze means defined in claim 5, wherein said fuze means further includes detecting and firing circuit means selectively responsive to said firing signal.
Claim 8
Dependent Claim
151 words
The optical fuze means defined in claim 1, wherein said optical transmitter means comprises alternate pulser-driver means driven at said predetermined frequency; first and second light emitting means alternately driven by said pulser-driver means to emit first and second alternating trains of light pulses; and optical means transmitting said first and second pulse trains, respectively, to said first and second foci; and wherein said optical receiving means comprises first and second photodetector means responding exclusively to reflected illumination from said first and second foci, respectively, when said target transits said focal plane and collectively to said illumination from said foci at said substantially all other relative positions of said target and focal plane; and bistable circuit means driven between first and second stable states thereof by said first and second photodetector means when said target transits said focal plane and generating said firing signal of said predetermined frequency in response thereto.
Claim 9
Dependent Claim
25 words
The optical fuze means defined in claim 7, wherein said fuze means further includes detecting and firing circuit means selectively responsive to said firing signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |