Gullwing distortion corrected deflection circuitry for a square-planar picture tube
US4682085A · kind A · utility
8Cited by
1References
31Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 10, 1985 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | May 10, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/233
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Line and field deflection circuits generate line and field deflection currents in respective line and field deflection windings to scan a raster on the phosphor screen of a square-planar picture tube having an aspherical faceplate. The asphericity of the faceplate subjects the scanned raster to gullwing distortion. A gullwing distortion correction circuit is responsive to signals repeating at line and field rates, respectively, for modulating the field deflection current during a line deflection period within the field deflection trace interval in a manner that corrects gullwing distortion of a corresponding raster scan line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.