Patent US3560642A successfully refreshed from Google Patents.
US3560642A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Television satellite system
Assignee: United States Department of the Navy
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Filing: 1967-10-13
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Granted: 1971-02-02
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Expires: 1987-10-13
Abstract
Abstract The present invention generally relates to a long life television system carried aboard a passively stabilized satellite for continuously providing linearized, high resolution coverage of the earth or other body about which the satellite orbits. More specifically, the proposed system of the present invention operates on a line-scan principle; i.e., the satellite carries a lens system whose field of view is a narrow, elongated swath on the earth''s surface which advances due to the satellite orbital motion. A fiber optic assembly receives the light image from the lens system and transfers it, as a substantially square raster, to the photosensitive faceplate of an image dissector camera tube, for example, where the image is then electronically scanned at a rate dependent upon the time that it takes for the satellite''s field of view (image swath) to advance a distance corresponding to the width of one resolution element of the image dissector. The resulting output video information from the image dissector camera tube is then encoded, along with satellite altitude information, onto a transmitted carrier frequency. At the ground receiving station, the video information is decoded and is then transformed, by suitable electro-optical transducer means, into a visual display on a drum recorder or a cathode ray oscilloscope, for example. The proposed television system of the present invention also includes means for compensating or rectifying the video display to account for curvature of the earth.
Inventors
- 👤 Irvin H Schroader
- 👤 Theodore Wyatt
- 👤 George B Bush
- 👤 Charles J Swet
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 10:03
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/002; H04N7/005
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
233 words
In a satellite-borne television system, the combination comprising: means for stabilizing the three major axes of said satellite relative to the object about which said satellite orbits; photosensor means having a photosensitive image input surface; a lens system for viewing an elongated image swath on the surface of said object perpendicular to the suborbital track of said satellite and capable of dividing said image swath into a plurality of substantially equal resolution elements; fiber optic means operably connected between said lens system and said photosensor means for transferring said divided image swath as a substantially square raster to the photosensitive image input surface of said photosensor means; means for rectifying the image swath transferred to said photosensor means so as to minimize distortion of said image at the ends of said swath due to curvature of the object about which said satellite orbits; circuit means operably connected to said photosensor means for scanning said image raster to produce an electrical video output signal; transmitter means for transmitting a carrier signal to a receiving station; coding means responsive to said video output signal from said photosensor means for coding said carrier signal in accordance with said video signal; means at said receiving station for receiving and decoding said transmitted carrier signal; and display means operably connected to said receiving means for reconstructing a visual display of said image swath from said decoded video signal.
Claim 2
Dependent Claim
233 words
In a satellite-borne television system, the combination comprising: means for stabilizing the three major axes of said satellite relative to the object about which said satellite orbits; photosensor means having a photosensitive image input surface; a lens system for viewing an elongated image swath on the surface of said object perpendicular to the suborbital track of said satellite and capable of dividing said image swath into a plurality of substantially equal resolution elements; fiber optic means operably connected between said lens system and said photosensor means for transferring said divided image swath as a substantially square raster to the photosensitive image input surface of said photosensor means; means for rectifying the image swath transferred to said photosensor means so as to minimize distortion of said image at the ends of said swath due to curvature of the object about which said satellite orbits; circuit means operably connected to said photosensor means for scanning said image raster to produce an electrical video output signal; transmitter means for transmitting a carrier signal to a receiving station; coding means responsive to said video output signal from said photosensor means for coding said carrier signal in accordance with said video signal; means at said receiving station for receiving and decoding said transmitted carrier signal; and display means operably connected to said receiving means for reconstructing a visual display of said image swath from said decoded video signal.
Claim 3
Dependent Claim
45 words
The system as specified in claim 1 wherein said image rectifying means comprises different focal length lenses contained in said lens system and capable of causing all the segments of the image swath to be transferred to the photosensor means as equal length image lines.
Claim 4
Dependent Claim
33 words
The system as specified in claim 1 wherein said image rectifying means comprises tapered optical fibers included in said fiber optic means for providing increased magnification towards the ends of said image swath.
Claim 5
Dependent Claim
16 words
The system specified in claim 1 wherein said photosensor means is an image dissector camera tube.
Claim 6
Dependent Claim
18 words
The system specified in claim 1 wherein said satellite stabilizing means provides gravity gradient stabilization of said satellite.
Claim 7
Dependent Claim
120 words
The combination specified in claim 1 wherein: said photosensor means operates with a predetermined optimum resolution element; said fiber optic means includes a plurality of optical fiber bundles having one end disposed in alignment to receive light corresponding to a swath image segment and being configured to convert said image segment into a plurality of spaced-apart parallel image lines on the photosensitive image input surface of said photosensor means; and said lens system includes means for imaging said swath image segment as a line one resolution element wide onto the aligned ends of said optical fibers, whereby said fiber optic means transfers said entire image swath to said photosensor means as a substantially square raster of spaced-apart parallel image lines.
Claim 8
Dependent Claim
67 words
The combination specified in claim 6 wherein said circuit means scans the parallel image lines of said raster in succession corresponding to movement from one end to the other of said image swath and the time required for scanning said raster is substantially equal to the time in which the field of view of said satellite advances a distance corresponding to the dimension of one resolution element.
Claim 9
Dependent Claim
36 words
The combination specified in claim 4 wherein the video output signal from said image dissector is encoded onto said transmitted carrier as it is produced, whereby the receiving station receives said video signal in real time.
Claim 10
Dependent Claim
64 words
The combination specified in claim 1 further including: means for sensing the attitude of said satellite; means operably connected to said satellite attitude sensing means for coding said carrier signal in accordance with the attitude of said satellite; and means at said receiving station responsive to said attitude information for permitting the correlation of said displayed video signal with the attitude of said satellite.
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) | 1974-02-01 | 1974-08-03 | 1975-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-01 | 1978-08-03 | 1979-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-01 | 1982-08-03 | 1983-02-02 | $7700.00 | Window Closed / Lapsed |