US3684915A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Rectangular to polar display converter
Assignee: Westinghouse Electric Corp
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Filing: 1970-06-15
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Granted: 1972-08-15
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Expires: 1990-06-15
Abstract
Abstract Apparatus for converting a display for a CRT tube from rectangular coordinates to polar coordinates for radar and the like applications whereby the same CRT tube can be used to display television pictures or to produce a sector-scan PPI radar display while utilizing all elements of a scan converter memory in producing the PPI display.
Inventors
- 👤 Lloyd B Gangawere
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 02:02
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/04; G01S7/06; G01S7/10; G01S7/12; G01S7/14; G01S7/22
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
137 words
In apparatus for producing a sector-scan PPI radar display on the face of a CRT tube having horizontal and vertical electron beam deflection devices, the combination of means for producing a sine wave whose amplitude increases from a minimum to a maximum as the electron beam scans the face of said CRT tube in one direction, means for dividing said sine wave into separate sine waves of the same increasing amplitude characteristics but displaced in phase with respect to each other, means for producing horizontal sync pulses for said CRT tube, a plurality of gate circuits to which said separate sine waves are applied, means responsive to said horizontal sync pulses for producing enabling pulses for said gate circuits, and means connecting the output of said gate circuits to said horizontal and vertical electron beam deflection devices.
Claim 2
Dependent Claim
137 words
In apparatus for producing a sector-scan PPI radar display on the face of a CRT tube having horizontal and vertical electron beam deflection devices, the combination of means for producing a sine wave whose amplitude increases from a minimum to a maximum as the electron beam scans the face of said CRT tube in one direction, means for dividing said sine wave into separate sine waves of the same increasing amplitude characteristics but displaced in phase with respect to each other, means for producing horizontal sync pulses for said CRT tube, a plurality of gate circuits to which said separate sine waves are applied, means responsive to said horizontal sync pulses for producing enabling pulses for said gate circuits, and means connecting the output of said gate circuits to said horizontal and vertical electron beam deflection devices.
Claim 3
Dependent Claim
52 words
The apparatus of claim 1 including means for producing a sawtooth vertical sweep waveform for said CRT tube, means responsive to said horizontal sync pulses for chopping said sawtooth waveform, and filter means for filtering said chopped waveform to produce said sine wave whose amplitude increases from a minimum to a maximum.
Claim 4
Dependent Claim
73 words
The apparatus of claim 1 including means for producing vertical sync pulses for said CRT tube, intensity control grid means of said CRT tube, and compensating means connected to said intensity control grid means of said CRT tube responsive to both said vertical and said horizontal sync pulses and said sawtooth vertical sweep waveform for producing a series of pulses adapted to maintain a constant illumination on said face of said CRT tube.
References Cited (Backward Citations)
US2677785A
Cited
US2860284A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-15 | 1976-02-14 | 1976-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-15 | 1980-02-14 | 1980-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-15 | 1984-02-14 | 1984-08-15 | $7700.00 | Window Closed / Lapsed |