Read focus optimization for an optical disk drive
US6487146B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 13, 2000 |
| Grant date | Nov 26, 2002 |
| Priority date | — |
| Expiry date | Mar 13, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/24085
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Writing predetermined data pattern to an allocated segment of a disk drive and appropriately reading that one data pattern while varying the read focus characteristics provides for efficient and effective read focus optimization in an optical disk drive. In order to produce helpful data, the read focus offset is varied while reading the different segments of the data pattern, thus producing read out signals with different peak to peak amplitudes. This is compared to data which is obtained by reading the same data pattern while the offset is held constant. Optimization of the read focus offset is carried out and made possible by appropriate analysis of the waveforms produced when reading the predetermined data pattern in these two reading passes. By appropriately tracking the results of the various read focus offsets, an optimum read focus offset can be easily determined.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.