US3882534A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gated automatic tint control circuit
Assignee: GTE Sylvania Inc
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Filing: 1973-07-20
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Granted: 1975-05-06
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Expires: 1993-07-20
Abstract
Abstract Flesh tones of reproduced images in a color television receiver are enhanced by a gated automatic tint control circuit which includes first and second color demodulators each coupled to a chrominance signal source and to a phase shift network which is in turn coupled to a reference oscillator signal source. A switching means coupled to the phase shift network is also coupled to the output of one of the color demodulators. The switching means alters the phase shift network and the phase angle of the signals applied to the demodulators from the reference oscillator signal source in accordance with the output from one of the color demodulators. The television signal also includes the usual synchronization and high voltage deflection circuitry and a DC restorer circuit couples the horizontal deflection circuitry to the switching means. Thus, flesh tone enhancement and phase shifting of the reference oscillator signals is effected upon activation of the switching means in response to an output signal from one of the color demodulators.
Inventors
- 👤 Gopal Krishna Srivastava
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:34
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/643
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
152 words
In a color television receiver having chrominance and reference oscillator signal sources, a gated tint control circuit comprising: first demodulator means coupled to said chrominance and reference oscillator signal sources; second demodulator means coupled to said chrominance signal source; phase shift network means coupled to said reference oscillator signal source and to said first and second demodulator means; bias potential development means coupled to the output of one of said first and second demodulator means and to synchronization and high voltage development means; and switching means coupled to said phase shift network means and to said bias potential development means, said switching means altering said phase shift network to effect alterations in the phase angle of signals applied to said first and second demodulators in accordance with polarity reversal of a signal from said output of said one demodulator means whereby flesh tones are enhanced while green signal response remains substantially unaltered.
Claim 2
Dependent Claim
152 words
In a color television receiver having chrominance and reference oscillator signal sources, a gated tint control circuit comprising: first demodulator means coupled to said chrominance and reference oscillator signal sources; second demodulator means coupled to said chrominance signal source; phase shift network means coupled to said reference oscillator signal source and to said first and second demodulator means; bias potential development means coupled to the output of one of said first and second demodulator means and to synchronization and high voltage development means; and switching means coupled to said phase shift network means and to said bias potential development means, said switching means altering said phase shift network to effect alterations in the phase angle of signals applied to said first and second demodulators in accordance with polarity reversal of a signal from said output of said one demodulator means whereby flesh tones are enhanced while green signal response remains substantially unaltered.
Claim 3
Dependent Claim
23 words
The gated tint control circuit of claim 1 wherein said bias potential development means is in the form of a charge storage means.
Claim 4
Dependent Claim
87 words
The gated tint control circuit of claim 1 wherein said switching means is in the form of a comparator circuit having one electron device coupled to a potential source and a series connected diode and electron device coupled to said output of one of said demodulator means and to said phase shift network means whereby alterations in polarity of a potential from said demodulator means alters said phase shift network to shift the phase angle of signals applied to said demodulator from said reference oscillator signal source.
Claim 5
Dependent Claim
55 words
The gated tint control circuit of claim 1 wherein said phase shift network includes an inductor interconnecting said first and second demodulator means, a first capacitor coupling said inductor and second demodulator means to a potential reference level, and a second capacitor coupling said inductor, second demodulator means, and first capacitor to said switching means.
Claim 6
Dependent Claim
57 words
The gated tint control circuit of claim 1 wherein said color television receiver includes a synchronization and high voltage development means connected to a DC restorer network including a unidirectional conduction device coupled to said switching means for providing a low impedance to conduction in one direction and a high impedance to conduction in an opposite direction.
Claim 7
Dependent Claim
177 words
A gated tint control circuit for a color television receiver having chrominance and reference oscillator signal sources and synchronization and high voltage development circuitry comprising: first and second demodulator means coupled to said chrominance signal source; phase shift network means including an inductor coupled to said reference oscillator signal source and to said first and second demodulator means; a first capacitor coupled to said inductor, said second demodulator means, and to a potential reference level; and a second capacitor coupled to said inductor, first capacitor, and said second demodulator means; and switching means coupled to the output of one of said first and second demodulator means and to said phase shift network means for selectively coupling and decoupling said phase shift network and a potential reference level in accordance with polarity reversal of a signal from said output of one of said first and second demodulator means whereby the phase angle of signals applied to said demodulator from said reference oscillator signal sources is altered in accordance with alterations in polarity of said output from said demodulator.
Claim 8
Dependent Claim
177 words
A gated tint control circuit for a color television receiver having chrominance and reference oscillator signal sources and synchronization and high voltage development circuitry comprising: first and second demodulator means coupled to said chrominance signal source; phase shift network means including an inductor coupled to said reference oscillator signal source and to said first and second demodulator means; a first capacitor coupled to said inductor, said second demodulator means, and to a potential reference level; and a second capacitor coupled to said inductor, first capacitor, and said second demodulator means; and switching means coupled to the output of one of said first and second demodulator means and to said phase shift network means for selectively coupling and decoupling said phase shift network and a potential reference level in accordance with polarity reversal of a signal from said output of one of said first and second demodulator means whereby the phase angle of signals applied to said demodulator from said reference oscillator signal sources is altered in accordance with alterations in polarity of said output from said demodulator.
Claim 9
Dependent Claim
26 words
The gated tint control circuit of claim 6 including DC restorer means coupled to said synchronization and high voltage development circuitry and to said sWitching means.
Claim 10
Dependent Claim
43 words
The gated tint control circuit of claim 6 wherein said switching means is coupled to a DC restorer means connected to said synchronization and high voltage development circuitry and AC coupled to said output of one of said first and second demodulator means.
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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) | 1978-05-05 | 1978-11-04 | 1979-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-05 | 1982-11-04 | 1983-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-05 | 1986-11-04 | 1987-05-06 | $7700.00 | Window Closed / Lapsed |