Optical head apparatus including two light sources and one photodetector
US6980505B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 2002 |
| Grant date | Dec 27, 2005 |
| Priority date | — |
| Expiry date | Dec 10, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In an optical head apparatus including a first light source for emitting a first light beam having a first wavelength, a second light source for emitting a second light beam having a second wavelength different from the first wavelength, an objective lens, a photodetector, and first and second optical combining/splitting elements, the first optical combining/splitting element receives the first light beam from the first light source to outgo most of the first light beam therefrom to the second optical combining/splitting element and receives the first and second light beams from the second optical combining/splitting element to outgo most of the first and second light beams therefrom to the photodetector. The second optical combining/splitting element receives the first light beam from the first optical combining/splitting element and the second light beam from the second light source to outgo most of the first and second light beams therefrom to the objective lens and receives the first and second light beams from the objective lens to outgo most of the first and second light beams therefrom to the first optical combining/splitting element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.