Optical disc system and method for controlling bias coil and light source to process information on a storage medium
US6434087B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 7, 1995 |
| Grant date | Aug 13, 2002 |
| Priority date | — |
| Expiry date | Jun 7, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B11/10558
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical disc system for storing information on a medium includes a light source, a focusing mechanism, and a tracking mechanism wherein the mechanisms are controlled by a feedback loop and the focusing mechanism focuses light emitted by the light source onto the medium to effect writing of information thereon. The system is provided with an electronic circuit for generating a servo error signal that is communicated in the feedback loop for effecting corrections of the focusing mechanism and the tracking mechanism. The system is further provided with a driver for energizing the light source, a bias coil disposed proximate to the medium, a bias coil driver switchably connected to the bias coil for supplying an electric current thereto, a current monitoring circuit connected to the bias coil driver having an output responsive to the electric current, and a controller connected to the output of the current monitoring circuit and to the driver. The controller thereby enables the driver when the output of the current monitoring circuit exceeds a predetermined magnitude so that information processed through the focusing mechanism is written onto the medium when the electric current flo…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.