US3558812A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aerial reconnaissance system
Assignee: Optische Industrie de Oude Delft NV
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Filing: 1967-11-13
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Granted: 1971-01-26
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Expires: 1987-11-13
Abstract
Abstract Infrared aerial reconnaissance system of the line scanning type in which, for a wide range of velocity-altitude ratio (v/h) conditions, objectionable line patterns in the strip photograph produced by the flying spot recorder are avoided by varying the width of the spot traces on the film with the rate at which the film is moved past the exposure station.
Inventors
- 👤 Leo Heinrich Josef Fr Beckmann
- 👤 Leendert Van Den Berg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:24
CPC Classifications
G; G01; G01S; G01S1/00; G01S1/02; G01C; G01C11/00; G01C11/02; G01C11/025; G03; G03B; G03B15/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
199 words
A system for recording a picture of a terrain from an airplane on a photographic film strip, comprising a scanner producing an electric video signal by periodically scanning at a constant rate a narrow strip of the terrain extending crosswise to the course of flight, and a photographic recorder having a light source, means to modulate the intensity of the light source in response to the video signal, means to derive a moving light spot from said light source which spot periodically scans the film strip crosswise in synchronism with the scanner, and means to feed the film strip lengthwise at a uniform rate controllable in response to variations of the ratio between the ground velocity and the altitude of the airplane, said system being characterized in that said means to derive the scanning light spot are arranged so that the spot has approximately rectangular shape, and in that means are provided to vary the dimension of the spot lengthwise of the film strip with the speed of the film strip in such a manner that the tracks made by the spot on the film will be substantially contiguous at various film speeds corresponding to various conditions of flight.
Claim 2
Independent Claim
199 words
A system for recording a picture of a terrain from an airplane on a photographic film strip, comprising a scanner producing an electric video signal by periodically scanning at a constant rate a narrow strip of the terrain extending crosswise to the course of flight, and a photographic recorder having a light source, means to modulate the intensity of the light source in response to the video signal, means to derive a moving light spot from said light source which spot periodically scans the film strip crosswise in synchronism with the scanner, and means to feed the film strip lengthwise at a uniform rate controllable in response to variations of the ratio between the ground velocity and the altitude of the airplane, said system being characterized in that said means to derive the scanning light spot are arranged so that the spot has approximately rectangular shape, and in that means are provided to vary the dimension of the spot lengthwise of the film strip with the speed of the film strip in such a manner that the tracks made by the spot on the film will be substantially contiguous at various film speeds corresponding to various conditions of flight.
Claim 3
Independent Claim
321 words
A system for recording a picture of a terrain from an airplane on a photographic film strip, comprising a scanner producing an electric video signal by periodically scanning at a constant rate a narrow strip of the terrain extending crosswise to the course of flight, and a photographic recorder having a light source, means to modulate the intensity of the light source in response to the video signal, means to derive a moving light spot from said light source which spot periodically scans the film strip crosswise in synchronism with the scanner, and means to feed the film strip lengthwise at a uniform rate controllable in response to variations of the ratio between the ground velocity and the altitude of the airplane, said system being characterized in that said means to derive the scanning light spot are arranged so that the spot has approximately rectangular shape, means are provided to vary the dimension of the spot lengthwise of the film strip with the speed of the film strip in such a manner that the tracks made by the spot on the film will be substantially contiguous at various film speeds corresponding to various conditions of flight, means are provided to curve the film strip laterally at the place where it is scanned by said spot so that it conforms to a portion of a cylinder, and in which said scanning spot deriving means comprises a diaphragm lighted by said light source, a microscope objective for imaging the diaphragm on the curved film which has its optical axis perpendicular to the axis of said cylinder and is arranged for rotation about such cylinder axis in synchronism with the scanner, and an oblique mirror rotatable in unison with the microscope objective and reflecting light from the diaphragm toward the microscope objective, said diaphragm being a slit diaphragm arranged for rotation in unison with said microscope objective and having a variable effective slit length.
Claim 4
Independent Claim
321 words
A system for recording a picture of a terrain from an airplane on a photographic film strip, comprising a scanner producing an electric video signal by periodically scanning at a constant rate a narrow strip of the terrain extending crosswise to the course of flight, and a photographic recorder having a light source, means to modulate the intensity of the light source in response to the video signal, means to derive a moving light spot from said light source which spot periodically scans the film strip crosswise in synchronism with the scanner, and means to feed the film strip lengthwise at a uniform rate controllable in response to variations of the ratio between the ground velocity and the altitude of the airplane, said system being characterized in that said means to derive the scanning light spot are arranged so that the spot has approximately rectangular shape, means are provided to vary the dimension of the spot lengthwise of the film strip with the speed of the film strip in such a manner that the tracks made by the spot on the film will be substantially contiguous at various film speeds corresponding to various conditions of flight, means are provided to curve the film strip laterally at the place where it is scanned by said spot so that it conforms to a portion of a cylinder, and in which said scanning spot deriving means comprises a diaphragm lighted by said light source, a microscope objective for imaging the diaphragm on the curved film which has its optical axis perpendicular to the axis of said cylinder and is arranged for rotation about such cylinder axis in synchronism with the scanner, and an oblique mirror rotatable in unison with the microscope objective and reflecting light from the diaphragm toward the microscope objective, said diaphragm being a slit diaphragm arranged for rotation in unison with said microscope objective and having a variable effective slit length.
Claim 5
Dependent Claim
60 words
A system as claimed in claim 2, in which the slit of the diaphragm extends parallel to said cylinder axis so as to be moved in a cylindrical surface when the diaphragm is rotated, further reflecting means rotatable in unison with the diaphragm being provided on both sides of the slit to form a radial light path through the slit.
Claim 6
Dependent Claim
42 words
A system as claimed in claim 3, in which a cylindrical sleeve is provided which is coaxial with the cylindrical surface in which the diaphragm is moved, said sleeve being axially slidable so as to vary the effective length of the slit.
Claim 7
Dependent Claim
20 words
A system as claimed in claim 2, in which the slit of the diaphragm extends perpendicularly to said cylinder axis.
Claim 8
Dependent Claim
27 words
A system As claimed in claim 5 in which the effective slit length is varied by an iris diaphragm fixedly mounted in alignment with said cylinder axis.
Claim 9
Dependent Claim
42 words
A system as claimed in claim 5, in which means are provided to light the slit diaphragm with a light beam derived from the light source and having a circular cross section of variable diameter at the place of the slit diaphragm.
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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) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |