Optical disk reproducing device
US6490234B1 · kind B1 · utility
10Cited by
2References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2000 |
| Grant date | Dec 3, 2002 |
| Priority date | — |
| Expiry date | Mar 14, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08511
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Through a provision of a level holding circuit in a focus servo mechanism for an optical disk reproducing device, a detection signal level with regard to a focusing position error, when a detection signal corresponding to a received optical beam amount shows a maximum value under a condition when not being changed over to an automatic focus loop, is sampled as an offset amount and, is held in advance in the level holding circuit, and the thus held level is utilized for effecting an automatic focusing under a just focusing servo condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.