Optical head and information recording and reproducing apparatus using it
US6396790B2 · kind B2 · utility
1Cited by
4References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 25, 2001 |
| Grant date | May 28, 2002 |
| Priority date | — |
| Expiry date | Sep 25, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0916
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical head having a plurality of laser light source and a plurality of photodetectors corresponding to the plurality of laser light sources. The plurality of laser light sources have at least three wavelengths with frequencies which are different from one another, a first laser module includes at least two laser light sources with two frequencies which are in close proximity and two photodetectors corresponding to the at least two laser light sources, and a second laser module includes another laser light source and another photodetector corresponding to the another laser light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.