Television raster centering aid
US4282461A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1979 |
| Grant date | Aug 4, 1981 |
| Priority date | — |
| Expiry date | Nov 29, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/05
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A television raster centering aid comprises means for blanking a horizontal scan line located at the center of the vertical deflection field. In an illustrative embodiment, an operational amplifier is used to indicate the presence of the deflection field center based on the polarity of the current in the vertical deflection windings. A gating circuit receives information from the operational amplifier and from a source of horizontal synchronizing pulses. The gating circuit then generates a signal which is used to blank a horizontal scan line located at the vertical deflection center. In one embodiment the raster centering aid is used in a yoke adjustment machine for blanking a scan line in a flat-field video display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.