Tracking controller and seek controller for optical recording device
US5742568A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1996 |
| Grant date | Apr 21, 1998 |
| Priority date | — |
| Expiry date | Jun 5, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08529
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A control circuit for use in an optical disk apparatus, which includes a carriage provided with a focus moving mechanism for supporting an objective lens; a carriage driving circuit for driving the carriage; and a tracking error detecting circuit for detecting a tracking error signal which represents a displacement of the light beam form the center of the information track. In the control circuit, a tracking control loop for performing a tracking control by feeding back a dc-component and ac-components, with frequencies which are not more than 10 kHz, of the tracking error signal to the carriage driving circuit is formed. Further, a filter device for attenuating the gain of the tracking control loop correspondingly to a frequency in the vicinity of a resonance frequency in a direction, in which the focus moving mechanism or the carriage crosses the information track, is provided in the tracking control loop. Moreover, the open-loop or overall gain crossover frequency of the tracking control loop is not less than 2 kHz.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.