Single means for converting beam widths of plural laser beams with different entry and exit angle with offset
US6947367B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 2001 |
| Grant date | Sep 20, 2005 |
| Priority date | — |
| Expiry date | Feb 28, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/094
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A low-profile optical disk device which performs recording and reproducing using a plurality of laser light sources with different wavelengths, without thug need for additional components. It is used as a DVD-Ram, CD-R or the like. It comprises a plurality of neighboring laser light sources with different wavelengths: a beam-shaping prism for expanding the width of laser beams in a direction in which the plural laser light sources are arranged; and a focus lens which forms an optical spot on an optical disk, where laser light sources with longer wavelengths are positioned closer to an extension line of a refracted beam created by the beam-shaping prism. The above arrangement enables correction of optical spot coma aberrations caused by a laser light source positioned out of the optical axis of the focus lens, thereby realizing a low-profile optical disk device with high optical performance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.