Active focus alignment system for multilayer optical disk storage based on dither frequency doubling
US5740145A · kind A · utility
18Cited by
10References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1996 |
| Grant date | Apr 14, 1998 |
| Priority date | — |
| Expiry date | Apr 1, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0013
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Laser light is focused in an accurate manner on selected layers in a multilayer optical disk recording system by means of an analysis of output electrical signals from a dithered source which results in the production of an electrical signal which is proportional to an amount by which the parts of the system are to be relatively moved in order to achieve the desired focus on one of the layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.