US3936870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic gain control for color television camera with reproduced color fidelity
Assignee: Sony Corp
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Filing: 1974-05-28
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Granted: 1976-02-03
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Expires: 1994-05-28
Abstract
Abstract A color television camera is disclosed in which level detector circuits are supplied with a plurality of color signals; a control signal, produced by the level detectors when any one of the color signals exceeds a predetermined level, is applied to an automatic gain control circuit connected in a transmission path for a picked up output; and the automatic gain control circuit is supplied with a control signal based upon a luminance signal when the former-mentioned control signal is not obtained.
Inventors
- 👤 Takashi Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 16:50
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/10; H04N23/12
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
136 words
Color television camera apparatus, comprising an image pickup tube; color filter means for forming color separated images of a viewed object on said image pickup tube; means for deriving a composite color video signal from said image pickup tube representative of said color separated images, said composite signal including a luminance signal and a chrominance signal, the latter being comprised of plural color components; means for separating said composite color video signal into said luminance and chrominance signals, respectively; level control means for controlling the magnitude of said composite color video signal in response to said luminance signal when none of said color components of said chrominance signal exceeds a predetermined level; and means for controlling said level control means with a different signal when a color component of said chrominance signal exceeds said predetermined level.
Claim 2
Dependent Claim
136 words
Color television camera apparatus, comprising an image pickup tube; color filter means for forming color separated images of a viewed object on said image pickup tube; means for deriving a composite color video signal from said image pickup tube representative of said color separated images, said composite signal including a luminance signal and a chrominance signal, the latter being comprised of plural color components; means for separating said composite color video signal into said luminance and chrominance signals, respectively; level control means for controlling the magnitude of said composite color video signal in response to said luminance signal when none of said color components of said chrominance signal exceeds a predetermined level; and means for controlling said level control means with a different signal when a color component of said chrominance signal exceeds said predetermined level.
Claim 3
Dependent Claim
40 words
Color television camera apparatus as claimed in claim 1, in which said color filter means comprises a first set of striped color filters and a second set of striped color filters, the first and second set intersecting with each other.
Claim 4
Dependent Claim
36 words
Color television camera apparatus as claimed in claim 1 wherein said level control means includes a control input, and further comprising switch means coupled to said control input for selectively supplying said separated luminance signal thereto.
Claim 5
Dependent Claim
47 words
Color television camera apparatus as claimed in Claim 3 further comprising detecting means for detecting when a color component of said chrominance signal exceeds said predetermined level to operate said switch means to thereby prevent said separated luminance signal from being supplied to said level control means.
Claim 6
Dependent Claim
71 words
Color television camera apparatus as claimed in Claim 4 wherein said detecting means comprises a plurality of level detectors for detecting the levels of said color components, respectively; and further comprising means for supplying the output of a level detector to said control input of said level control means for controlling said level control means when the level of said color component detected by said level detector exceeds said predetermined level.
Claim 7
Dependent Claim
28 words
Color television camera apparatus as claimed in claim 5, in which said level control means is a circuit which controls a target voltage of said image pickup tube.
Claim 8
Dependent Claim
20 words
Color television camera apparatus as claimed in Claim 5 wherein said level control means comprises an automatic gain control circuit.
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) | 1979-02-02 | 1979-08-04 | 1980-02-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-02-02 | 1983-08-04 | 1984-02-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-02-02 | 1987-08-04 | 1988-02-03 | $7700.00 | Window Closed / Lapsed |