US4335333A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Raster scan color display system and method having improved pin cushion non-linearity correction
Assignee: HP Inc
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Filing: 1980-01-29
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Granted: 1982-06-15
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Expires: 2000-01-29
Abstract
Abstract A raster scan color display system for a CRT includes a vertical sweep system wherein a parabolic signal repeating at the horizontal sweep rate is multiplied with a vertical sweep signal corresponding to a linear ramp repeating at a vertical deflection rate. The output is differentiated and capacitively coupled to a wideband voltage drive vertical deflection amplifier to provide pin-cushion non-linearity correction.
Inventors
- 👤 Michael Ramsay
- 👤 Warren Pratt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:15
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/16; H04N3/22; H04N3/23; H04N3/233; H04N3/2335
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
98 words
Vertical deflection apparatus for a scanning system having a vertical deflection scanning rate and a horizontal scanning rate comprising: first means for producing a parabolic signal having a repetition rate at the horizontal deflection rate; second means for producing a ramp signal having a repetition rate at the vertical deflection rate; third means coupled to the first means and the second means for multiplying the parabolic signal and the ramp signal and producing the product as an output; and fourth means coupled to the third means for differentiating the third means output and producing a pin-cushion correction signal.
Claim 2
Dependent Claim
98 words
Vertical deflection apparatus for a scanning system having a vertical deflection scanning rate and a horizontal scanning rate comprising: first means for producing a parabolic signal having a repetition rate at the horizontal deflection rate; second means for producing a ramp signal having a repetition rate at the vertical deflection rate; third means coupled to the first means and the second means for multiplying the parabolic signal and the ramp signal and producing the product as an output; and fourth means coupled to the third means for differentiating the third means output and producing a pin-cushion correction signal.
Claim 3
Dependent Claim
50 words
Apparatus as in claim 1 comprising: a vertical deflection amplifier having an output, a first input coupled to the fourth means output and a second input; and a vertical deflection yoke having a main winding coupled to the amplifier output and a sense winding coupled to the amplifier second input.
Claim 4
Dependent Claim
20 words
Apparatus as in claim 2 wherein the vertical deflection amplifier first input is capacitively coupled to the fourth means output.
Claim 5
Dependent Claim
58 words
Apparatus as in claim 2 comprising: compensation means having an output coupled to the vertical deflection amplifier first input and being coupled to receive the vertical deflection amplifier output and to receive a vertical centering reference voltage for comparing the vertical deflection amplifier output with the vertical centering reference voltage and producing an output corresponding to the comparison.
Claim 6
Dependent Claim
39 words
Apparatus as in claim 4 comprising switch means coupled to receive a retrace signal and to the compensation means for allowing the compensation means to produce its output only during vertical retrace in response to receiving the retrace signal.
Claim 7
Dependent Claim
109 words
Deflection apparatus for a display system having a first deflection scanning rate in a first direction and a second deflection scanning rate in a second direction comprising: first means for producing a parabolic signal having a repetition rate at the first deflection scanning rate; second means for producing a ramp signal having a repetition rate at the second deflection scanning rate; third means coupled to the first means and the second means for multiplying the parabolic signal and the ramp signal and producing the product as an output; and fourth means coupled to the third means for differentiating the third means output and producing a second direction deflection signal.
Claim 8
Dependent Claim
109 words
Deflection apparatus for a display system having a first deflection scanning rate in a first direction and a second deflection scanning rate in a second direction comprising: first means for producing a parabolic signal having a repetition rate at the first deflection scanning rate; second means for producing a ramp signal having a repetition rate at the second deflection scanning rate; third means coupled to the first means and the second means for multiplying the parabolic signal and the ramp signal and producing the product as an output; and fourth means coupled to the third means for differentiating the third means output and producing a second direction deflection signal.
Claim 9
Dependent Claim
47 words
Apparatus as in claim 6 comprising: a deflection amplifier having an output, a first input coupled to the fourth means output and a second input; and deflection means having a main winding coupled to the amplifier output and a sense winding coupled to the amplifier second input.
Claim 10
Dependent Claim
18 words
Apparatus as in claim 7 wherein the amplifier first input is capacitively coupled to the fourth means output.
Claim 11
Dependent Claim
48 words
Apparatus as in claim 7 comprising: compensation means having an output coupled to the amplifier first input and being coupled to receive the amplifier output and to receive a reference voltage for comparing the amplifier output with the reference voltage and producing an output corresponding to the comparison.
Claim 12
Dependent Claim
39 words
Apparatus as in claim 9 comprising switch means coupled to receive a sample signal and to the compensation means for allowing the compensation means to apply its output to the amplifier only in response to receiving the sample signal.
Claim 13
Independent Claim
91 words
A method for producing a pin-cushion distortion corrected deflection signal for a raster scan display system having a first deflection scanning rate in a first direction and a second deflection scanning rate in a second direction comprising the steps of: generating a parabolic signal having a repetition rate at the first deflection scanning rate; generating a ramp signal having a repetition rate at the second deflection scanning rate; multiplying the ramp signal and the parabolic signal to produce a product signal; and differentiating the product signal to produce a correction signal.
Claim 14
Independent Claim
91 words
A method for producing a pin-cushion distortion corrected deflection signal for a raster scan display system having a first deflection scanning rate in a first direction and a second deflection scanning rate in a second direction comprising the steps of: generating a parabolic signal having a repetition rate at the first deflection scanning rate; generating a ramp signal having a repetition rate at the second deflection scanning rate; multiplying the ramp signal and the parabolic signal to produce a product signal; and differentiating the product signal to produce a correction signal.
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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) | 1985-06-14 | 1985-12-14 | 1986-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-06-14 | 1989-12-14 | 1990-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-06-14 | 1993-12-14 | 1994-06-15 | $7700.00 | Window Closed / Lapsed |