Optical head and optical data recording and reproducing apparatus having the same
US5703856A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1994 |
| Grant date | Dec 30, 1997 |
| Priority date | — |
| Expiry date | Oct 17, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical head for reproducing data from first and second optical disks which are different from each other in at least one of a base material thickness and an available wavelength, includes: a first light source for emitting a first light beam, the first light beam being used for reproducing data from the first optical disk: an optical system designed to converge the first light beam onto the first optical disk in accordance with a base material thickness and an available wavelength of the first optical disk: and a second light source for emitting a second light beam, the second light beam being used for reproducing data from the second optical disk, wherein an optical path length between the second light source and the optical system is different from an optical path length between the first light source and the optical system, and wherein the optical system converges the second light beam onto the second optical disk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.