Method and apparatus for changing laser beam power of an optical storage device for various types of compact disks
US5991251A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 29, 1997 |
| Grant date | Nov 23, 1999 |
| Priority date | — |
| Expiry date | Sep 29, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/004
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A layer beam controller for an optical storage apparatus includes a laser beam generator, a laser beam power varier for varying the laser beam power to first, second, and third power levels, a memory for storing predetermined reference values including first reference values corresponding to the first power level and second reference values corresponding to the second power level, a light amount detector for detecting a light amount of the laser beam, a laser beam power corrector for correcting the laser beam power at the respective power level by comparing the light amount and a corresponding one of the predetermined reference values selected by a type of the compact disk in operation in the optical storage apparatus. The laser beam controller further includes a power level assigner for assigning the first, second and third power levels based on the type of disk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.