Optical pickup compatible with a plurality of types of optical disks having different thicknesses
US6574182B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 19, 2001 |
| Grant date | Jun 3, 2003 |
| Priority date | — |
| Expiry date | Apr 19, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an optical pickup device (10) including a laser light source (1) and an objective lens (7), an optical device (6) is provided that transmits a laser beam of 635 nm in wavelength emitted from a first semiconductor laser (1A) straightforwardly into the objective lens (7) while maintaining its incident intensity, and that selectively diffracts a laser beam of 780 nm in wavelength emitted from a second semiconductor laser (1B) to a desired direction while maintaining its incident intensity and directs only the predetermined center portion of the laser beam into the objective lens (7). The optical pickup device (10) records or reproduces a signal onto or from a plurality of types of optical disks differing in substrate thickness while directing a laser beam of sufficient intensity onto a signal recording plane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.