Optical pick-up device and objective lens used therein
US7075880B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2002 |
| Grant date | Jul 11, 2006 |
| Priority date | — |
| Expiry date | Sep 25, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup apparatus conducts recording or reproducing information for an information recording plane of a first or second optical information recording medium and comprises a first light source and a second light source mounted on a same base board; a converging optical system; and a coupling lens. The converging optical system comprises an objective lens to converge a first or second light flux having passed through the coupling lens on a first or second optical information recording medium; and a diffractive structure to change a focal length in accordance with a wavelength of a light flux emitted from the first light source or the second light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.