US4047204A
Expired / Lapsed
US
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Variable interlace display
Assignee: American Optical Corp
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Filing: 1976-09-07
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Granted: 1977-09-06
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Expires: 1996-09-07
Abstract
Abstract Apparatus for utilization in driving a raster-type display, such as is used in the familiar television system for producing a selectable (according to a predetermined group) of raster formats of different raster interlace rates.
Inventors
- 👤 James J. Gold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:38
CPC Classifications
H; H01; H01J; H01J37/00; H01J37/26; H01J37/28; H04; H04N; H04N7/00; H04N7/01; H04N7/18
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
157 words
In apparatus for varying according to a predetermined selection range the interlace rate of a rastered display, such as on a cathode ray tube including a horizontal deflection control circuit and a vertical deflection control circuit connected respectively to a horizontal drive and a vertical drive, the improvement comprising: variable oscillation means to generate a principal frequency to drive said horizontal and vertical drives, said frequency being a multiple of the horizontal deflection rate and the predetermined interlace rates; horizontal counter means for reducing the oscillation frequency to a frequency equal to the horizontal rate for the predetermined interlace rate; vertical counter means for reducing the oscillation frequency equal to the vertical rate for the predetermined interlace rate; and control means for said vertical counter and said oscillation means which cause the quotient of said horizontal rate divided by said vertical rate to be a fractional number, the fractional portion of which represents the desired interlace rate.
Claim 2
Dependent Claim
157 words
In apparatus for varying according to a predetermined selection range the interlace rate of a rastered display, such as on a cathode ray tube including a horizontal deflection control circuit and a vertical deflection control circuit connected respectively to a horizontal drive and a vertical drive, the improvement comprising: variable oscillation means to generate a principal frequency to drive said horizontal and vertical drives, said frequency being a multiple of the horizontal deflection rate and the predetermined interlace rates; horizontal counter means for reducing the oscillation frequency to a frequency equal to the horizontal rate for the predetermined interlace rate; vertical counter means for reducing the oscillation frequency equal to the vertical rate for the predetermined interlace rate; and control means for said vertical counter and said oscillation means which cause the quotient of said horizontal rate divided by said vertical rate to be a fractional number, the fractional portion of which represents the desired interlace rate.
Claim 3
Dependent Claim
24 words
The improvement according to claim 1 wherein said variable oscillation means is phase-locked to the frequency of the main power supply for said display.
Claim 4
Dependent Claim
24 words
The improvement according to claim 1 wherein said horizontal rate for said display is substantially equal to the horizontal rate of commercial television systems.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-09-05 | 1981-03-07 | 1981-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-09-05 | 1985-03-07 | 1985-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-09-05 | 1989-03-07 | 1989-09-06 | $7700.00 | Window Closed / Lapsed |