Optical medium judging method for avoiding the collision of an objective lens with a disk
US7345266B2 · kind B2 · utility
2Cited by
2References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 14, 2004 |
| Grant date | Mar 18, 2008 |
| Priority date | — |
| Expiry date | May 8, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0956
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to an optical medium judging method for avoiding the collision of an objective lens with a disk or the failure to judge a warped disk when the optical disk drive judging the disk. This method will move the objective lens so as to obtain the data of the laser beam reflection amount of the focusing beam on the plastic layer of the optical disk. By using the reflection amount, the driving circuit will output a rising direct current voltage of a voltage difference to drive an actuator so as to move the objective lens to a proper position capable of judging the disk without colliding with the disk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.