Optical memory apparatus and focus servo control method
US6633523B1 · kind B1 · utility
9Cited by
7References
32Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 4, 2000 |
| Grant date | Oct 14, 2003 |
| Priority date | — |
| Expiry date | Apr 4, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08511
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical memory apparatus has an offset inserting unit for inserting a predetermined offset to the focus error signal, and a focus servo pull-in determining unit for inserting, when the focus servo control unit executes focus servo pull-in, offset to the focus error signal, detecting level change of the focus error signal and determining success or failure of focus servo pull-in.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.