Optical disc track access apparatus and method for optical disc reproducer
US6791915B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 18, 1999 |
| Grant date | Sep 14, 2004 |
| Priority date | — |
| Expiry date | Mar 18, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/08505
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a track access apparatus and a method by which an optical pick-up unit quickly accesses a destination track of an optical disc by controlling a tracking actuator using a back electromotive force by detecting the vibration of an objective lens, the position variation, and the distortion of an actuator which occur when the optical pick-up unit is moved across the tracks of the optical disc at a high speed. In the present invention, there are provided a photodetector for detecting the amount of the beams of a side spot and a main beam spot based on two sub-beams and one main beam, a differential amplifier for differentiating the two signals of the sub-beams and outputting a tracking error signal, a first phase/gain compensation unit for compensating the phase and gain of the tracking error signal, a position detection unit for detecting the position of the objective lens from two signals of the main beam, a second phase/gain compensation unit for compensating the phase and gain of the lens position detection signal, a microcontroller for outputting a switch control signal, a switch for selecting an output of a first or second phase/gain compensation un…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.