Light emitting module and optical pickup apparatus and method employing the same
US7450476B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 9, 2004 |
| Grant date | Nov 11, 2008 |
| Priority date | — |
| Expiry date | Aug 12, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/1398
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A light emitting module and method and an optical pickup apparatus employing the same are provided. The light emitting module includes a base, a semiconductor laser that is disposed on the base and emits a laser beam of a predetermined wavelength, a cap surrounding the semiconductor laser, a beam shaping window that is fitted with a predetermined portion of the cap corresponding to the propagation path of the laser beam and shapes a transmitted laser beam while reflecting a portion of an incident beam, and a quarter wave plate that is disposed in the propagation path of the laser beam and in front of the beam shaping window and transforms a laser beam horizontally polarized after passing through the beam shaping window into a circularly polarized beam while converting a beam reflected from an optical disc into a vertically polarized beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.