Super-resolution optical disc reader and read method optimized through reflectivity measurement
US8355303B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2010 |
| Grant date | Jan 15, 2013 |
| Priority date | — |
| Expiry date | Jan 29, 2031 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/1267
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The invention relates to the field of the optical recording of information on a medium, such as an optical disc. To read an optical disc in super-resolution mode, a procedure for optimizing the power of the read laser beam is implemented. This optimization is based on the observation that a correlation exists between the power allowing the disc to be read without risk in super-resolution mode and the reflectivity of the sensitive layer containing the information. The reflectivity of the optical disc is measured for several power levels of the read laser, a critical power is determined on the basis of the reflectivity measurements made, and a read power sufficiently above the critical power, so as to be well outside a range of power levels entailing risks, is selected according to the critical power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.