Spherical aberration detector and optical pickup device
US6498330B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 8, 1999 |
| Grant date | Dec 24, 2002 |
| Priority date | — |
| Expiry date | Dec 8, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a light detecting device for detecting light beams passing through a light-gathering optical system, an aberration detector of the present invention includes photodetectors for forming a light-gathering spot of a first light beam passing near an optical axis, and photodetectors for forming a light-gathering spot of a second light beam passing outside the first light beam. In accordance with detection signals of the detectors, a spherical aberration of the light-gathering optical system can be detected. With this arrangement, a spherical aberration appearing on the light-gathering optical system is precisely detected and corrected in an appropriate manner, so that it is possible to suitably record and reproduce information in a magneto-optical disk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.