Objective lens, optical head, and optical pickup apparatus
US7656774B2 · kind B2 · utility
0Cited by
5References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Mar 24, 2005 |
| Grant date | Feb 2, 2010 |
| Priority date | — |
| Expiry date | Sep 20, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/13727
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An objective lens for at least one of recording and reproducing for an optical information recording medium includes in the order from a light source side: a first lens group having negative refracting power, which is in a meniscus shape having a concave surface facing the light source side; a second lens group having positive refracting power; and a third lens group having positive refracting power, which is in a meniscus shape having a concave surface facing an image side.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.