US4642690A
Expired / Lapsed
US
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Digital video signal processor with analog level control
Assignee: RCA Corp
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Filing: 1984-08-27
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Granted: 1987-02-10
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Expires: 2004-08-27
Abstract
Abstract In a video signal processing and display system such as a television receiver employing digital video signal processing techniques, viewer generated control signals for normally controlling the brightness and/or contrast of a displayed image are utilized in analog rather than digital form for controlling the magnitude of the video signal.
Inventors
- 👤 Werner Hinn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:56
CPC Classifications
H; H04; H04N; H04N11/00; H04N11/04; H04N5/00; H04N5/44; H04N5/57
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
256 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; means for providing viewer generated analog control signals for controlling the magnitude of said output analog video signals coupled to said display means; and means for coupling said control signals to said display means in analog form via a signal path exclusive of a signal path including said digital video signal processor; wherein said digital-to-analog signal converter means corresponds to a video output driver stage for providing to said intensity control electrode of said display means said analog signal version of digital output signals with a magnitude for directly driving said intensity control electrode, said digital-to-analog converter means having a plurality of inputs for receiving respective bits of said digital video signal for combining said bits so as to directly produce at an output said analog signal with a magnitude for directly driving said intensity control electrode; and said analog control signals are applied to said driver stage for controlling the magnitude of analog video signals coupled to said display means.
Claim 2
Dependent Claim
256 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; means for providing viewer generated analog control signals for controlling the magnitude of said output analog video signals coupled to said display means; and means for coupling said control signals to said display means in analog form via a signal path exclusive of a signal path including said digital video signal processor; wherein said digital-to-analog signal converter means corresponds to a video output driver stage for providing to said intensity control electrode of said display means said analog signal version of digital output signals with a magnitude for directly driving said intensity control electrode, said digital-to-analog converter means having a plurality of inputs for receiving respective bits of said digital video signal for combining said bits so as to directly produce at an output said analog signal with a magnitude for directly driving said intensity control electrode; and said analog control signals are applied to said driver stage for controlling the magnitude of analog video signals coupled to said display means.
Claim 3
Dependent Claim
79 words
A system according to claim 1, wherein said providing means provides first and second control signals; said first control signal is coupled to said driver stage to control the gain thereof for varying the peak-to-peak amplitude of said analog video output signals from said driver stage; and said second control signal is coupled to said driver stage to control the DC output level thereof for varying the DC content of said analog video output signals from said driver stage.
Claim 4
Dependent Claim
106 words
A system according to claim 2, wherein said driver stage comprises an array of MOS transistor devices each having gate, drain and source electrodes; said gate electrodes are interconnected in common; said source electrodes receive respective ones of said information bits as input signals; said drain electrodes are connected in common to said intensity control electrode of said display means via said analog video signal path for providing said analog video output signals thereto; a load impedance is coupled to said interconnected drain electrodes; said first control signal is coupled to said interconnected gate electrodes; and said second control signal is coupled to said load impedance.
Claim 5
Dependent Claim
91 words
A system according to claim 2, and further comprising means for generating a third control signal for effecting white balance control of images displayed by said display means, said third control signal being coupled to said driver stage for controlling the peak-to-peak amplitude of said analog video output signals from said driver stage; and means for generating a fourth control signal for controlling the output bias of said driver stage, said fourth control signal being coupled to the output of said driver stage for maintaining a desired output DC bias level.
Claim 6
Dependent Claim
38 words
A system according to claim 3 and further comprising a further transistor device coupled between the output of said driver stage and said load impedance, and forming a cascode video signal amplifier with said array of transistor devices.
Claim 7
Dependent Claim
181 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; and means for providing a viewer generated analog contrast control signal for controlling the peak-to-peak amplitude of said output analog video signals coupled to said display means; wherein said converter means comprises an array of MOS transistor devices with gate electrodes interconnected in common for receiving said contrast control signal, with source electrodes for receiving respective ones of said information bits as input signals, and with drain electrodes connected in common to said intensity control electrode of said display means via said analog video signal path.
Claim 8
Dependent Claim
181 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; and means for providing a viewer generated analog contrast control signal for controlling the peak-to-peak amplitude of said output analog video signals coupled to said display means; wherein said converter means comprises an array of MOS transistor devices with gate electrodes interconnected in common for receiving said contrast control signal, with source electrodes for receiving respective ones of said information bits as input signals, and with drain electrodes connected in common to said intensity control electrode of said display means via said analog video signal path.
Claim 9
Dependent Claim
175 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; and means for providing an analog control signal for effecting white balance control of images displayed by said display means; wherein said converter means comprises an array of MOS transistor devices with gate electrodes interconnected in common for receiving said white balance control signal, with source electrodes for receiving respective ones of said information bits as input signals, and with drain electrodes connected in common to said intensity control electrode of said display means via said analog video signal path.
Claim 10
Dependent Claim
175 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; and means for providing an analog control signal for effecting white balance control of images displayed by said display means; wherein said converter means comprises an array of MOS transistor devices with gate electrodes interconnected in common for receiving said white balance control signal, with source electrodes for receiving respective ones of said information bits as input signals, and with drain electrodes connected in common to said intensity control electrode of said display means via said analog video signal path.
Claim 11
Dependent Claim
209 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; and means for providing a viewer generated analog brightness control signal for controlling the DC level of said output analog video signals coupled to said display means; wherein said converter means comprises an array of MOS transistor devices with gate electrodes interconnected in common, with source electrodes for receiving respective ones of said information bits as input signals, and with drain electrodes connected in common to said intensity control electrode of said display means and to a load impedance; and a further MOS transistor device has a gate electrode coupled to said commonly connected gate electrodes, a drain electrode coupled to said load impedance, and a source electrode for receiving said brightness control signal.
Claim 12
Dependent Claim
209 words
A digital video signal processing and display system comprising: a source of digital video signals comprising plural binary information bits representative of image information to be displayed; digital signal processor means for digitally processing said video signals; digital-to-analog signal converter means for providing an output analog signal version of digital output signals from said digital processor; image display means responsive to video signals applied to an intensity control electrode thereof; an analog video signal path for coupling said output analog video signals from said converter means to said intensity control electrode of said display means; and means for providing a viewer generated analog brightness control signal for controlling the DC level of said output analog video signals coupled to said display means; wherein said converter means comprises an array of MOS transistor devices with gate electrodes interconnected in common, with source electrodes for receiving respective ones of said information bits as input signals, and with drain electrodes connected in common to said intensity control electrode of said display means and to a load impedance; and a further MOS transistor device has a gate electrode coupled to said commonly connected gate electrodes, a drain electrode coupled to said load impedance, and a source electrode for receiving said brightness control signal.
Claim 13
Dependent Claim
69 words
A system according to claim 8 and further comprising keyed bias control means with an input coupled to said analog video signal path for monitoring the black level of said output analog video signals from said converter means during video image blanking intervals for developing an output bias control signal at an output, said output bias control signal being coupled to said source electrode of said further transistor device.
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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) | 1990-02-09 | 1990-08-11 | 1991-02-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-02-09 | 1994-08-11 | 1995-02-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-02-09 | 1998-08-11 | 1999-02-10 | $7700.00 | Window Closed / Lapsed |