Optical information storage apparatus having cylindrical lens for eliminating astigmatism generated by polarization beam splitter and newly generating astigmatism
US6167018A · kind A · utility
7Cited by
6References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 17, 1998 |
| Grant date | Dec 26, 2000 |
| Priority date | — |
| Expiry date | Mar 17, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information storage apparatus is constructed to include a light source, a polarization beam splitter reflecting a light beam emitted from the light source and irradiating a reflected light beam on a recording surface of a recording medium, a first part for eliminating a coma aberration which is generated due to a light beam which is reflected by the recording surface and passes through the polarization beam splitter, a second part for eliminating an astigmatism which is generated by the polarization beam splitter and the first part, and a third part for generating an astigmatism.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.