Optical pickup apparatus, objective optical element and optical information recording reproducing apparatus
US7672212B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 2007 |
| Grant date | Mar 2, 2010 |
| Priority date | — |
| Expiry date | Aug 6, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup apparatus according to the present invention includes: a first light source for emitting a first light flux; a second light source for emitting a second light flux; a third light source for emitting a third light flux; and an objective optical element. The objective optical element has an optical surface including at least two areas provided with optical path difference providing structures. The objective optical element converges the first to third light fluxes each passing through the predetermined areas on the objective optical element onto respective information recording surfaces of the first to third optical disks. The first optical path difference providing structure is a ring-shaped structure which includes a plurality of ring-shaped zones including respective steps having at least two kinds of amounts selected from the predetermined expressions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.