Optical pickup and a wedge beam splitter
US7251209B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 2003 |
| Grant date | Jul 31, 2007 |
| Priority date | — |
| Expiry date | Oct 6, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup for a recording medium includes a light source, an objective lens, a main photodetector, and a front photodetector. The configuration of the optical pickup enables converging or diverging of light to be incident on a plate beam splitter so that light can be received at an effective light receiving region of a front photodetector without interference due to internal reflection occurring in the plate beam splitter. In the alternative, a wedge beam splitter in the optical pickup includes first and second mirror planes at a predetermined angle to transmit and reflect incident light at a predetermined ratio. In the optical pickup, an amount of light that is exactly proportional to an output power of the light source can be detected, where the output power of the light source can be accurately controlled, thereby improving a linearity of the output power of the light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.