Optical pickup for improving properties of a reproduction signal
US6785209B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 8, 2001 |
| Grant date | Aug 31, 2004 |
| Priority date | — |
| Expiry date | Feb 12, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/1356
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup capable of focusing a main light spot and an auxiliary light spot including optical aberration when an optical disk is not tilted, and analyzing the main light spot and the auxiliary light spot with a photodetector, thereby correcting aberration. The optical pickup includes a light source emitting light; light splitting means for splitting an incident beam into at least two light beams including a first beam and a second beam so as to form at least two light spots on an optical disk; optical path changing means for changing the traveling path of the incident first and second beams; an objective lens focusing the first and second beams to form a main light spot and an auxiliary light spot, respectively, on the optical disk; a photodetector having first and second light receiving portions receiving the first and second beams reflecting from the optical disk and passing through the optical path changing means, respectively, and performing photoelectric conversion on the received beams to produce and detect electrical signals; and a signal processor correcting aberration caused by tilting of the optical disk, using the electrical signals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.