Optical pick-up
US7280445B2 · kind B2 · utility
1Cited by
2References
4Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Nov 12, 2004 |
| Grant date | Oct 9, 2007 |
| Priority date | — |
| Expiry date | May 10, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0013
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A finite optical system that a laser beam from a light source is allowed to be directly incident on an objective lens without passing a collimate lens is employed. The reference position of the objective lens is set so that converged light from the objective lens forms a focal point on a recording layer remoter from the light source of two recording layers in an optical disk. The objective lens moves in a direction of the light source side from the reference position to perform a focusing operation and read information recorded on the recording layer nearer to the light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.