Feed-back circuit for controlling the distance between vertically displaced scanning rasters produced by a cathode ray tube
US3953671A · kind A · utility
1Cited by
4References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Sep 27, 1974 |
| Grant date | Apr 27, 1976 |
| Priority date | — |
| Expiry date | Sep 27, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/36
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Errors in the raster of a flying spot scanner are measured by placing a semi-reflecting surface in the path of the light to the object being scanned to form a secondary raster image in a position where such measurements can be made without interfering with the primary scanning operation. Preferably a feed-back circuit is used to control the cathode ray tube in dependence upon the measurement.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.