US4841379A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Time-base error correction apparatus for video tape or disk player
Assignee: Pioneer Corp
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Filing: 1987-09-17
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Granted: 1989-06-20
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Expires: 2007-09-17
Abstract
Abstract A time-base error correction circuit for use in a video disk player, video tape player, or the like, with which all residual time-base error is eliminated. A detector circuit detects the amount of residual time-base error between the reproduced video signal and a write clock signal. A variable delay circuit disposed prior to a memory in which the video signal is stored adjusts the delay of the reproduced video signal accordingly.
Inventors
- 👤 Toru Akiyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:52
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/87; H04N9/89; H04N9/896
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
142 words
A time-base error correction apparatus comprising: an A/D converter circuit for analog-to-digital conversion of an input video signal on the basis of a write clock; a memory for storing an output of said A/D converter circuit; a D/A converter circuit for digital-to-analog conversion of an output of said memory on the basis of a read clock; a separator circuit for separating a synchronizing signal from said video signal; a PLL circuit for generating said write clock in response to an output of said separator circuit; a detector circuit for producing a residual time-base error signal representing an amount of time-base error between said video signal and said write clock; and a variable delay circuit for delaying said video signal on the basis of said residual time-base error signal, a resulting delayed signal being applied to an input of said A/D converter circuit.
Claim 2
Dependent Claim
142 words
A time-base error correction apparatus comprising: an A/D converter circuit for analog-to-digital conversion of an input video signal on the basis of a write clock; a memory for storing an output of said A/D converter circuit; a D/A converter circuit for digital-to-analog conversion of an output of said memory on the basis of a read clock; a separator circuit for separating a synchronizing signal from said video signal; a PLL circuit for generating said write clock in response to an output of said separator circuit; a detector circuit for producing a residual time-base error signal representing an amount of time-base error between said video signal and said write clock; and a variable delay circuit for delaying said video signal on the basis of said residual time-base error signal, a resulting delayed signal being applied to an input of said A/D converter circuit.
Claim 3
Dependent Claim
72 words
The time-base error correction apparatus of claim 1, wherein said detector circuit comprises a separator circuit for separating a color burst signal from said video signal, a frequency divider for frequency dividing said write clock by a predetermined factor, and a phase comparator for comparing in phase said color burst signal and an output of said frequency divider, said residual time-base error signal being produced at an output of said phase comparator.
Claim 4
Dependent Claim
121 words
The time-base error correction apparatus of claim 1, wherein said detector circuit comprises a first separator circuit for separating a color burst signal from said video signal, a second separator circuit for separating a horizontal synchronizing signal from said video signal, a pulse generator receiving as inputs said color burst signal and said horizontal synchronizing signal and producing a pulse by detecting one cycle of said color burst signal at a predetermined time after arrival of a pulse of said horizontal synchronizing signal, and a phase comparator receiving as inputs an output of a frequency divider of said PLL circuit and an output of said pulse generator, said residual time-base error signal being produced as an output of said phase comparator.
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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) | 1992-06-19 | 1992-12-19 | 1993-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-19 | 1996-12-19 | 1997-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-19 | 2000-12-19 | 2001-06-20 | $7700.00 | Window Closed / Lapsed |