Digital convergence correcting apparatus
US4977446A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jan 27, 1989 |
| Grant date | Dec 11, 1990 |
| Priority date | — |
| Expiry date | Jan 27, 2009 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/28
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A convergence correcting apparatus is used in a projection television receiver including a CRT having an aspherical fluorescent screen and a projection lens apparatus which is attached to the display screen of the CRT and has aspherical plastic lenses. In the digital convergence correcting apparatus, a digital memory stores digital correction data corresponding to correction values of convergence adjustments points indicative of a plurality of points on the display screens divided in the horizontal and vertical directions. A multiplexer reads out predetermined digital correction data from the digital memory and time sharingly multiplexes. At least one digital/analog converter receives the time sharingly multiplexed data from the multiplexer and generates an analog signal. Sample and hold circuits extract a predetermined correction signal from the analog output of the digital/analog converter and sample and hold them. The convergence correcting apparatus is driven in accordance with the respective correction signals held by the sample and hold circuits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.