US3787611A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for correcting color television signals
Assignee: Robert Bosch Fernsehanlagen GmbH
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Filing: 1972-08-31
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Granted: 1974-01-22
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Expires: 1992-08-31
Abstract
Abstract A system for correcting complete color television signals, including luminance, color saturation and hue signals. A first channel delays the signal while a second channel derives the necessary corrections for the delayed first channel signal.
Inventors
- 👤 D Poetsch
- 👤 H Hess
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:08
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
254 words
A system for correcting color television signals, in which the contrast of the luminance signal, the color saturation, and the hue are corrected, comprising: A. a first channel for delaying the color television signals; B. a second channel connected in parallel with the first channel for forming a correction signal, comprising: B1. a contrast correcting circuit, B2. a dark-desaturation circuit, B3. a total saturation circuit, B4. a circuit for correcting hue, and B5. a first addition circuit for receiving outputs from the contrast correcting circuit, the darkdesaturation circuit, the total saturation regulator, and the hue correcting circuit, C. the dark-desaturation circuit comprising: C1. a limiter, C2. a modulator fed by the limiter, and C3. means with automatic-volume control responsive to an output of the limiter for producing an amplified, phase-inverted signal wherein the elements in the dark-desaturation circuit are connected in series, in which structure an input of the modulator is connected to the output of a second addition circuit, the luminance signal is transmitted to the input of the limiter, and inputs of the first and a third addition stage are connected to the output of the phase inverter stage; D. wherein the auxiliary chrominance carrier is separated from the color television signal and is transmitted to the second and third addition circuit, to which also the output signal of the hue correction circuit is transmitted; E. and wherein the total saturation regulator is arranged between the output of the third addition circuit and one of the inputs of the first addition circuit.
Claim 2
Independent Claim
254 words
A system for correcting color television signals, in which the contrast of the luminance signal, the color saturation, and the hue are corrected, comprising: A. a first channel for delaying the color television signals; B. a second channel connected in parallel with the first channel for forming a correction signal, comprising: B1. a contrast correcting circuit, B2. a dark-desaturation circuit, B3. a total saturation circuit, B4. a circuit for correcting hue, and B5. a first addition circuit for receiving outputs from the contrast correcting circuit, the darkdesaturation circuit, the total saturation regulator, and the hue correcting circuit, C. the dark-desaturation circuit comprising: C1. a limiter, C2. a modulator fed by the limiter, and C3. means with automatic-volume control responsive to an output of the limiter for producing an amplified, phase-inverted signal wherein the elements in the dark-desaturation circuit are connected in series, in which structure an input of the modulator is connected to the output of a second addition circuit, the luminance signal is transmitted to the input of the limiter, and inputs of the first and a third addition stage are connected to the output of the phase inverter stage; D. wherein the auxiliary chrominance carrier is separated from the color television signal and is transmitted to the second and third addition circuit, to which also the output signal of the hue correction circuit is transmitted; E. and wherein the total saturation regulator is arranged between the output of the third addition circuit and one of the inputs of the first addition circuit.
Claim 3
Dependent Claim
89 words
A system according to claim 1, wherein the circuit for correcting hue comprises: A. a chrominance carrier regenerator B. three essentially equal channels and C. a fourth addition circuit connected to receive the outputs of the three equal channels, wherein each of the three channels comprises, in series connection, a phase shifter, a PAL switch, a modulator, and an automatic-volume-control amplifier and wherein luminance signals are transmitted to the inputs of the modulators in which structure a different amplitude range of the luminance signals is provided for each channel.
Claim 4
Dependent Claim
66 words
A system according to claim 1, wherein the delayed color televisioN signals of the first channel and the output signal of the first addition circuit are added and transmitted to a further automatic volume control amplifier; and wherein the output signal of the further automatic volume control amplifier and the output signal of the first addition circuit are both added to the delayed color television signals.
Claim 5
Dependent Claim
68 words
A system according to claim 3, wherein, for the adjustment of the black-level value of the correction signals, a blanking pulse of adjustable amplitude and polarity is transmitted to a further input of the first addition circuit, and wherein, a clamping circuit is provided between an addition circuit, which follows the further automatic-volume-control amplifier and an addition circuit which adds the delayed television signals and the correction signals.
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) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |