Compatible optical pickup and light output amount detecting method performed in the compatible optical pickup
US7403458B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 29, 2004 |
| Grant date | Jul 22, 2008 |
| Priority date | — |
| Expiry date | Jan 21, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A compatible optical pickup, including first and second light sources for emitting lights with different wavelengths and first and second photodetectors for detecting an information signal and/or an error signal, and a method of detecting the amount of output light using the compatible optical pickup. The first and second photodetectors monitor the amount of light output from the second and first light sources respectively such that no extra front photodetectors are required. Thus, the number of optical component parts included in the optical pickup can be reduced, thereby lowering the manufacturing costs for the optical pickup. Also, there is no need to secure a space in a base where a front photodetector is to be installed, so the base is simplified. Thus, inferior moldings are reduced, and the durability of a mold can be prolonged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.