Patent US3702376A successfully refreshed from Google Patents.
US3702376A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Comb filter circuit
Assignee: Sony Corp
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Filing: 1970-12-14
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Granted: 1972-11-07
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Expires: 1990-12-14
Abstract
Abstract A comb filter circuit for separating luminance and chrominance signal components from a composite color television signal transmitted with the luminance and chrominance signal components in a frequency interleaved relation, comprises a delay means for delaying the composite color television signal by one horizontal scanning period and a bridge circuit connected to the delay means and consisting of four sections of substantially equal impedance. To the bridge circuit the delayed and non-delayed composite color television signals are suppled and therein the addition and the subtraction of both signals are performed, so that the luminance and chrominance signals are derived separately from the output terminals of the bridge circuit.
Inventors
- 👤 Katsuo Isono
- 👤 Hisao Okada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:50
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/77; H04N9/78; H03; H03H; H03H11/00; H03H11/02; H03H11/34
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
148 words
A comb filter circuit for separating luminance and chrominance signal components from a composite color television signal which is transmitted with a frequency interleaving relation between said luminance and chrominance signal components, comprising delay means for delaying said composite signal by substantially one horizontal scanning period and for producing first and second delayed signals of opposite polarities to each other, bridge circuit means including four arms of substantially equal impedance and first and second pairs of opposed connecting points between said arms, means for supplying said first and second delayed signals to the opposed connecting points, respectively, of said first pair thereof, means for supplying said composite signal to at least one of said connecting points of said second pair thereof, and output terminals connected with one of said pairs of opposite connecting points so that the luminance and chrominance signal components respectively appear at said output terminals.
Claim 2
Dependent Claim
148 words
A comb filter circuit for separating luminance and chrominance signal components from a composite color television signal which is transmitted with a frequency interleaving relation between said luminance and chrominance signal components, comprising delay means for delaying said composite signal by substantially one horizontal scanning period and for producing first and second delayed signals of opposite polarities to each other, bridge circuit means including four arms of substantially equal impedance and first and second pairs of opposed connecting points between said arms, means for supplying said first and second delayed signals to the opposed connecting points, respectively, of said first pair thereof, means for supplying said composite signal to at least one of said connecting points of said second pair thereof, and output terminals connected with one of said pairs of opposite connecting points so that the luminance and chrominance signal components respectively appear at said output terminals.
Claim 3
Dependent Claim
24 words
A comb filter circuit according to claim 1, in which said output terminals are respectively connected with said first pair of opposed connecting points.
Claim 4
Dependent Claim
44 words
A comb filter circuit according to claim 1, further comprising a low-pass filter having a frequency band lower than that of said delayed signals and through which said composite signal is also supplied to the other of said connecting points of said second pair.
Claim 5
Dependent Claim
28 words
A comb filter circuit according to claim 1, further comprising impedance means through which the other of said connecting points of said second pair is connected to ground.
Claim 6
Dependent Claim
17 words
A comb filter circuit according to claim 4, in which said impedance means consists of a capacitor.
Claim 7
Dependent Claim
30 words
A comb filter circuit according to claim 4, in which said impedance means consists of a resonance circuit having a low impedance at the frequency band of said delayed signals.
Claim 8
Dependent Claim
26 words
A comb filter circuit according to claim 1, further comprising amplifier means for amplifying said composite signal prior to the passage thereof through said delay means.
Claim 9
Dependent Claim
53 words
A comb filter circuit according to claim 7, in which said amplifier means includes means for controlling the level of the composite signal supplied by said amplifier means to said delay means so that said delayed signals and said composite signal are supplied to said bridge circuit means at substantially the same level.
References Cited (Backward Citations)
US2855573A
Cited
US2729698A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-11-07 | 1976-05-08 | 1976-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-07 | 1980-05-08 | 1980-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-07 | 1984-05-08 | 1984-11-07 | $7700.00 | Window Closed / Lapsed |