Optical disk apparatus and focus jump method for multilayer optical disk
US8154961B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 14, 2009 |
| Grant date | Apr 10, 2012 |
| Priority date | — |
| Expiry date | May 4, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0013
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention provides an optical disk apparatus and a focus jump method capable of reliably performing a focus jump by appropriately obtaining the amplitude of a signal such as a focus error signal in a multilayer optical disk. An optical disk includes jump areas which are provided separately from data areas and at which a focus jump is performed. When a focus jump is performed, an optical pickup is moved to the jump area, and the laser power level of the optical pickup is changed and set in accordance with a target layer to which the focus is jumped. A focus position is allowed to reach the target layer by counting the number of times of intersecting with recording layers using a reflected light from the optical disk while performing a focus sweep of an objective lens in the optical pickup.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.