US3890499A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential scanner system
Assignee: United States Department of the Army
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Filing: 1970-05-15
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Granted: 1975-06-17
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Expires: 1990-05-15
Abstract
Abstract A coaxial differential scanner for sensing and mapping wherein the brightness of the scanned element of an object or target to be observed has subtracted from it the average brightness of its proximate surroundings. Radiation from the scanned element of the object is directed onto a first of two coaxially disposed detectors, while radiation from the surrounding area or background is directed onto the second detector. The outputs of the two detectors are combined in a differential device, with the difference output eventually used to modulate a recording source, such as a lamp whose image is scanned across a film or other recording medium in synchronism with the scanning of the scanned object.
Inventors
- 👤 Bernard Lippel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 13:53
CPC Classifications
G; G02; G02B; G02B26/00; G02B26/08; G02B26/10; H; H04; H04N; H04N23/00; H04N23/20
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
143 words
A dual scanner comprising means for scanning an object emitting electromagnetic radiation, a first detector responding to the electromagentic radiation emitted from each scanned element of said object, and a second detector responsive to radiant energy emanating from a background surrounding said element said first and second detectors providing electrical signals, circuit means for subtracting an electrical signal from said second detector from an electrical signal from said first detector to provide a difference signal, means for separately recording said difference signal and said signal from said second detector on separate recording means, separate means for playing back said separately recorded signals, means for combining said separately played back signals, said combined signal being applied to an energy source to modulate the intensity thereof, and means including a scanner device synchronized with said scanning means for directing said energy onto a recording device.
Claim 2
Dependent Claim
143 words
A dual scanner comprising means for scanning an object emitting electromagnetic radiation, a first detector responding to the electromagentic radiation emitted from each scanned element of said object, and a second detector responsive to radiant energy emanating from a background surrounding said element said first and second detectors providing electrical signals, circuit means for subtracting an electrical signal from said second detector from an electrical signal from said first detector to provide a difference signal, means for separately recording said difference signal and said signal from said second detector on separate recording means, separate means for playing back said separately recorded signals, means for combining said separately played back signals, said combined signal being applied to an energy source to modulate the intensity thereof, and means including a scanner device synchronized with said scanning means for directing said energy onto a recording device.
Claim 3
Dependent Claim
23 words
A dual scanner as recited in claim 1 wherein said second detector surrounds said first detector and is coaxial with said first detector.
Claim 4
Dependent Claim
19 words
A scanner according to claim 1 further including means for varying the relative amplitudes of said played back signals.
Claim 5
Dependent Claim
19 words
A scanner according to claim 2 further including means for varying the relative amplitudes of said played back signals.
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) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |