US4553141A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Picture control for RGB monitor
Assignee: Zenith Electronics LLC
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Filing: 1982-09-21
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Granted: 1985-11-12
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Expires: 2002-09-21
Abstract
Abstract A color monitor includes R G and B gain blocks, in the form of balanced multipliers, and a potentiometer picture control for supplying a common DC gain control voltage to the differentially coupled transistor pairs in the gain blocks. A common black level control adjusts the zero level for the signals. Changes in gain control voltage do not affect black level or color balance of the picture tube display.
Inventors
- 👤 Michael D. Flasza
- 👤 David K. Nienaber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:07
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/64; H04N9/73
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
157 words
A color monitor for developing a color display in response to input R G and B color signals, each of which color signals includes both chrominance information and luminance information, said display being produced by a color picture tube and exhibiting color balance and color black level determined by the amplitude of said input color signals and the characteristics of said color picture tube, comprising: a plurality of inputs for receiving said input color signals and a corresponding plurality of outputs for supplying said color signals to said picture tube; a plurality of matched gain blocks coupled between said inputs and said outputs for amplifying said color signals, each said gain block including balanced multiplier means for enabling simultaneous control of the levels of said color signals in said gain blocks without upsetting said color balance and said black level of said display; and picture control means applying a common gain control voltage to said gain blocks.
Claim 2
Dependent Claim
157 words
A color monitor for developing a color display in response to input R G and B color signals, each of which color signals includes both chrominance information and luminance information, said display being produced by a color picture tube and exhibiting color balance and color black level determined by the amplitude of said input color signals and the characteristics of said color picture tube, comprising: a plurality of inputs for receiving said input color signals and a corresponding plurality of outputs for supplying said color signals to said picture tube; a plurality of matched gain blocks coupled between said inputs and said outputs for amplifying said color signals, each said gain block including balanced multiplier means for enabling simultaneous control of the levels of said color signals in said gain blocks without upsetting said color balance and said black level of said display; and picture control means applying a common gain control voltage to said gain blocks.
Claim 3
Dependent Claim
17 words
A color monitor as set forth in claim 1 wherein said picture control means includes a potentiometer.
Claim 4
Dependent Claim
18 words
A color monitor as set forth in claim 2 wherein said gain control voltage is a DC potential.
Claim 5
Dependent Claim
20 words
A color monitor as set forth in claim 3 wherein said balanced multiplier means each include balanced differentially coupled transistors.
Claim 6
Dependent Claim
28 words
A color monitor as set forth in claim 4 further including: a common black level control for varying the voltage corresponding to zero level of said color signals.
Claim 7
Dependent Claim
44 words
A color monitor as set forth in claim 5 wherein each of said gain blocks further includes a pair of current mirrors, one current mirror in each said pair coupling a respective one of said input color signals to said balanced differentially coupled transistors.
Claim 8
Dependent Claim
31 words
A color monitor as set forth in claim 6 further including: a common bias source supplying bias current to the other current mirror of each said pair in said gain blocks.
Claim 9
Dependent Claim
155 words
A color monitor for developing a color display from input R G and B color signals, on a color picture tube, said display exhibiting a color balance and black level determined by the amplitudes of said input R G and B color signals and the characteristics of said picture tube, comprising: a plurality of inputs for receiving said input R G and B color signals and a corresponding plurality of outputs for supplying said R G and B color signals to said picture tube; a plurality of matched gain blocks, each including balanced multiplier means comprising balanced differentially coupled transistors for simultaneously changing the levels of said R G and B color signals in response to a common DC gain control voltage without upsetting said color balance and said black level of said display; and picture control means including a potentiometer for applying a common DC gain control voltage to each of said gain blocks.
Claim 10
Dependent Claim
155 words
A color monitor for developing a color display from input R G and B color signals, on a color picture tube, said display exhibiting a color balance and black level determined by the amplitudes of said input R G and B color signals and the characteristics of said picture tube, comprising: a plurality of inputs for receiving said input R G and B color signals and a corresponding plurality of outputs for supplying said R G and B color signals to said picture tube; a plurality of matched gain blocks, each including balanced multiplier means comprising balanced differentially coupled transistors for simultaneously changing the levels of said R G and B color signals in response to a common DC gain control voltage without upsetting said color balance and said black level of said display; and picture control means including a potentiometer for applying a common DC gain control voltage to each of said gain blocks.
Claim 11
Dependent Claim
34 words
A color monitor as set forth in claim 8 further including: a common DC black level control for setting the voltage corresponding to zero signal level of said R G and B color signals.
Claim 12
Dependent Claim
45 words
A color signal monitor as set forth in claim 9 wherein each said gain block includes a first current mirror coupled to a respective one of said inputs and a second current mirror; and common bias means supplying bias current to said second current mirrors.
References Cited (Backward Citations)
US3838208A
Cited
US3927346A
Cited
US4086579A
Cited
US4180805A
Cited
US4348688A
Cited
US4450439A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-11-11 | 1989-05-13 | 1989-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-11-11 | 1993-05-13 | 1993-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-11-11 | 1997-05-13 | 1997-11-12 | $7700.00 | Window Closed / Lapsed |