Optical information storage device capable of giving optimum phase compensations according to recording tracks in reproducing information
US6442123B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 22, 1999 |
| Grant date | Aug 27, 2002 |
| Priority date | — |
| Expiry date | Oct 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10515
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information storage device for directing an incident light beam onto a recording medium having a recording surface composed of lands and grooves as tracks and detecting a reproduced signal from a reflected light beam from the recording medium. The optical information storage device includes a phase plate provided in an optical path of the reflected light beam so as to be tiltable between a first position where the phase plate gives to the reflected light beam a first phase compensation amount required for detection of signals from the lands and a second position where the phase plate gives to the reflected light beam a second phase compensation amount required for detection of signals from the grooves; and a drive mechanism for tilting the phase plate. Examples of the drive mechanism include a solenoid, DC motor, and voice coil motor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.