US3639684A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Field sequential laser scan for night color television
Assignee: TDK Micronas GmbH
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Filing: 1970-08-20
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Granted: 1972-02-01
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Expires: 1990-08-20
Abstract
Abstract A system for closed circuit or other television in low ambient light condition, said system being arranged for operation in either of two modes. A color television camera is equipped with red, blue and green filters which are applied field sequentially in a first mode of system operation and are unused in a second mode. Laser beam generating means are included and are adapted to generate three laser beams of colors corresponding to the filter colors. The laser generator is adapted to produce the three beam colors simultaneously during each frame in the first mode and field sequentially in the second mode. The laser beams are all directed into a common beam path which is passed through horizontal and vertical laser beam deflection devices to scan the laser beams synchronously with the camera scan. The deflection devices illustrated are preferably birefringent crystal devices which receive suitably amplified camera sweep signals and correspondingly vary their coefficients of refraction to produce laser beam scanning congruent with the camera scan. Economical illumination in a single-camera system is thereby effected, and the system is adapted to future developments in multicolor lasers.
Inventors
- 👤 Arnold M Levine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:18
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
184 words
A system for operation os a color television camera with insufficient ambient lighting, comprising: means for generating plural laser beams of predetermined different colors and means for optically combining said beams to form a combined beam for illuminating a scene to be televised; horizontal scanning means responsive to a first sweep control function for analogously changing the direction of said combined beam to produce horizontal scanning, said horizontal scanning means being light transmissive and being inserted in the path of said combined beam; vertical scanning mEans responsive to a second sweep control function for analogously changing the direction of said combined beam in a plane substantially normal to said horizontal scanning, to produce vertical scanning, said vertical scanning means being light transmissive and being inserted in the path of said combined beam; a nonintegrating color television camera having means for scanning in raster form; means synchronized by the horizontal and vertical scanning signals of said camera, for synchronously controlling the generation of said first and second sweep control functions respectively; and means for gating said laser generators into operation according to a predetermined program.
Claim 2
Independent Claim
184 words
A system for operation os a color television camera with insufficient ambient lighting, comprising: means for generating plural laser beams of predetermined different colors and means for optically combining said beams to form a combined beam for illuminating a scene to be televised; horizontal scanning means responsive to a first sweep control function for analogously changing the direction of said combined beam to produce horizontal scanning, said horizontal scanning means being light transmissive and being inserted in the path of said combined beam; vertical scanning mEans responsive to a second sweep control function for analogously changing the direction of said combined beam in a plane substantially normal to said horizontal scanning, to produce vertical scanning, said vertical scanning means being light transmissive and being inserted in the path of said combined beam; a nonintegrating color television camera having means for scanning in raster form; means synchronized by the horizontal and vertical scanning signals of said camera, for synchronously controlling the generation of said first and second sweep control functions respectively; and means for gating said laser generators into operation according to a predetermined program.
Claim 3
Dependent Claim
25 words
The invention set forth in claim 1, further defined in that said means for gating said laser generators produces operation of said lasers field sequentially.
Claim 4
Dependent Claim
45 words
The invention set forth in claim 1 in which said lasers are gated on contemporaneously, and in which said camera is equipped with a plurality of selectible filters and means for selecting said filter field sequentially with reference to the operation of said camera scan.
Claim 5
Dependent Claim
44 words
The invention set forth in claim 1 in which said laser beams generators are three in number each generating one of three arbitrary primary colors which are capable of producing each visual color by combination of said primary colors according to discrete tristimulus coefficients.
Claim 6
Dependent Claim
25 words
The invention set forth in claim 4 in which said three arbitrary primary laser colors and said corresponding camera filters are red, blue and green.
Claim 7
Dependent Claim
40 words
The invention set forth in claim 1 in which said horizontal and vertical scanning means comprise first and second light transmissive crystals capable of changing their indices of refraction in response to said first and second sweep control functions respectively.
Claim 8
Dependent Claim
17 words
The invention of claim 6 in which said light transmissive crystals are further defined as being birefringent.
Claim 9
Dependent Claim
21 words
The invention set forth in claim 7 in which said light transmissive crystals are of the deuterated potassium dihydrogen phosphate type.
Claim 10
Dependent Claim
54 words
The invention set forth in claim 2 in which said laser generators and said filters are operated in a red, blue, green sequence and the relative intensities of said laser generators are predetermined in a manner such as to produce a response, at said camera, comparable to that produced by steady state ambient lighting.
Claim 11
Dependent Claim
32 words
The invention set forth in claim 3 in which said horizontal and vertical scanning means comprise first and second birefringent light transmissive crystals responsive to corresponding ones of said sweep control functions.
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) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |