Patent US4425583A successfully refreshed from Google Patents.
US4425583A
Expired / Lapsed
US
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Video disc player having time base variations eliminated in both audio and video signals
Assignee: Universal Pioneer Corp
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Filing: 1981-05-05
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Granted: 1984-01-10
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Expires: 2001-05-05
Abstract
Abstract A video disc player in which undesirable frequency variations in reproduced video and audio signals due to absence of the color burst signal during the vertical retrace time are eliminated. A first control unit actuates a tangential mirror driver unit in response to a phase difference produced by comparing a horizontal synchronizing signal from the reproduced video signal with a reference color subcarrier signal. The video signal is delayed by an electronically-controlled variable delay line the delay time of which is set on accordance with a phase difference between the color burst signal and a reference horizontal synchronizing signal.
Inventors
- 👤 Hitoshi Kanamaru
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:07
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/87; H04N9/89; H04N9/893; G; G11; G11B; G11B19/00; G11B19/20; G11B19/28; G11B7/00; G11B7/08
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
287 words
A video disc player for reproducing video and audio signals recorded on a disc comprising: means for rotating a disc to be played; a mirror for directing a beam of light onto a recorded track on said disc to be played; an electromagnetic actuator for controlling a tilting angle of said mirror to tangentially adjust said beam relative to said recorded track; means for producing a reproduced electrical video signal in response to light reflected from said recording track; means for separating a horizontal synchronizing signal contained in said reproduced video signal from said reproduced video signal; means for separating a color burst signal contained in said reproduced video signal from said reproduced video signal; means for producing first and second reference synchronizing signals, said first reference synchronizing signal having a frequency corresponding to a predetermined horizontal synchronizing frequency and said second reference synchronizing signal having a frequency corresponding to a predetermined color burst frequency; first phase comparing means for producing a first control signal representing a phase difference between the horizontal synchronizing signal separated from said reproduced video signal and said first reference synchronizing signal; first control means for controlling said electromagnetic actuator in response to said first control signal; an electronically-controlled variable delay line for delaying said reproduced video signal; second phase comparing means for producing a second control signal representing a phase difference between the color burst signal separated from said video signal and said second reference synchronizing signal; and second control means for establishing the delay time of said electronically-controlled variable delay line in response to said second control signal for thereby establishing a delay time of said reproduced video signal between said reproducing video signal producing means and a video output terminal.
Claim 2
Dependent Claim
287 words
A video disc player for reproducing video and audio signals recorded on a disc comprising: means for rotating a disc to be played; a mirror for directing a beam of light onto a recorded track on said disc to be played; an electromagnetic actuator for controlling a tilting angle of said mirror to tangentially adjust said beam relative to said recorded track; means for producing a reproduced electrical video signal in response to light reflected from said recording track; means for separating a horizontal synchronizing signal contained in said reproduced video signal from said reproduced video signal; means for separating a color burst signal contained in said reproduced video signal from said reproduced video signal; means for producing first and second reference synchronizing signals, said first reference synchronizing signal having a frequency corresponding to a predetermined horizontal synchronizing frequency and said second reference synchronizing signal having a frequency corresponding to a predetermined color burst frequency; first phase comparing means for producing a first control signal representing a phase difference between the horizontal synchronizing signal separated from said reproduced video signal and said first reference synchronizing signal; first control means for controlling said electromagnetic actuator in response to said first control signal; an electronically-controlled variable delay line for delaying said reproduced video signal; second phase comparing means for producing a second control signal representing a phase difference between the color burst signal separated from said video signal and said second reference synchronizing signal; and second control means for establishing the delay time of said electronically-controlled variable delay line in response to said second control signal for thereby establishing a delay time of said reproduced video signal between said reproducing video signal producing means and a video output terminal.
Claim 3
Dependent Claim
30 words
The video disc player as claimed in claim 1 wherein said second and first reference synchronizing signals are a reference color subcarrier signal and a reference horizontal synchronizing signal, respectively.
Claim 4
Dependent Claim
20 words
The video disc player as claimed in claim 1 wherein said electronically-controlled variable delay line comprises a charge transfer device.
Claim 5
Dependent Claim
18 words
The video disc player as claimed in claim 3 wherein said charge transfer device comprises a charge-coupled device.
Claim 6
Dependent Claim
19 words
The video disc player as claimed in claim 3 wherein said charge transfer device comprises a bucket brigade device.
Claim 7
Dependent Claim
21 words
The video disc player as claimed in claim 1 wherein said electronically-controlled delay line comprises a coil and a varactor diode.
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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) | 1987-01-09 | 1987-07-11 | 1988-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-09 | 1991-07-11 | 1992-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-09 | 1995-07-11 | 1996-01-10 | $7700.00 | Window Closed / Lapsed |