Optical pickup apparatus for reading different types of recording media at different reading wavelengths
US6480456B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 2, 2000 |
| Grant date | Nov 12, 2002 |
| Priority date | — |
| Expiry date | Jan 26, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup apparatus which supports two wavelengths and is amenable to a reduction in size without employing a combining prism. The optical pickup apparatus employs a semiconductor laser device implemented in the form of a one-chip laser diode having two light sources for emitting a first laser beam and a second laser beam at a wavelength different from that of the first laser beam. A photodetector unit has a first detector section for receiving the first laser beam and a second detector section for receiving the second laser beam, and is set at positions at which the first and second laser beams follow return light paths of different lengths from an optical disc to the first and second detector sections.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.