Patent US4935807A successfully refreshed from Google Patents.
US4935807A
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Television receiver with auxiliary input connector providing a chrominance signal subjected to pre-distortion for video signals of a separated Y-C format
Assignee: RCA Licensing Corp
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Filing: 1989-04-20
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Granted: 1990-06-19
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Expires: 2009-04-20
Abstract
Abstract An auxiliary video input terminal (S-terminal) couples luminance and chrominance input signals to respective inputs of peaking circuits in the display processor of a receiver. The chrominance input signal is subjected to pre-distortion (de-peaking) to correct for sideband amplitude distortion in the chrominance peaking filter of the receiver thereby preventing color distortion in displayed images. The luminance signal is subjected to additional peaking at a frequency greater than the characteristic peaking frequency of the luminance peaking filter thereby enhancing the sharpness of wideband luminance input signals displayed by the receiver.
Inventors
- 👤 Gene K. Sendelweck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:10
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/641; H04N9/77; H04N9/646
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
94 words
Television apparatus comprising a display processor having a luminance input coupled to a first video source via a chrominance peaking circuit and coupled to a second video source via a circuit path; and wherein: said second video source is coupled via said circuit path to an input of said chrominance peaking circuit to which said first video source is coupled; and said circuit path includes a chrominance de-peaking circuit for subjecting a chrominance input signal provided by said second video source to peaking by said peaking circuit and to de-peaking by said de-peaking circuit.
Claim 2
Dependent Claim
94 words
Television apparatus comprising a display processor having a luminance input coupled to a first video source via a chrominance peaking circuit and coupled to a second video source via a circuit path; and wherein: said second video source is coupled via said circuit path to an input of said chrominance peaking circuit to which said first video source is coupled; and said circuit path includes a chrominance de-peaking circuit for subjecting a chrominance input signal provided by said second video source to peaking by said peaking circuit and to de-peaking by said de-peaking circuit.
Claim 3
Dependent Claim
34 words
Television apparatus as recited in claim 1 wherein said chrominance de-peaking circuit includes a filter for unbalancing the relative amplitudes of upper and lower sidebands of said chrominance signal provided by said second source.
Claim 4
Dependent Claim
18 words
Television apparatus as recited in claim 2 wherein said upper sideband is reduced relative to said lower sideband.
Claim 5
Dependent Claim
26 words
Television apparatus as recited in claim 3 wherein the sideband reduction of said de-peaking current is substantially complementary to sideband reduction provided by said peaking circuit.
Claim 6
Dependent Claim
31 words
Television apparatus as recited in claim 1 wherein said de-peaking current comprises a cascade connection including a termination network, a sideband distortion filter, an AC coupling network and a switch circuit.
References Cited (Backward Citations)
US4644387A
Cited
US4689663A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-18 | 1993-12-18 | 1994-06-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-18 | 1997-12-18 | 1998-06-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-18 | 2001-12-18 | 2002-06-19 | $7700.00 | Window Closed / Lapsed |