Multi-stage focus control system and method
US7092323B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 2002 |
| Grant date | Aug 15, 2006 |
| Priority date | — |
| Expiry date | Dec 31, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0941
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A focus control system for an optical pickup head is provided. The optical head generates an electronic signal in response to an optical signal. The focus control system comprises a focusing error signal generator, a focus control signal generator and an actuator. The focus control signal generator is electrically connected to the focusing error signal generator, and includes a first, a second and a third compensators with a first, a second and a third gains, respectively, for generating a focus control signal with one of the first, second and third gains in response to the focusing error signal according to a corresponding one of a first, a second and a third operating modes of the optical pickup head. A method for controlling movement of an optical pickup head is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.