Optical pickup
US6496453B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 26, 2001 |
| Grant date | Dec 17, 2002 |
| Priority date | — |
| Expiry date | Jul 10, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/0006
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical pickup hasa light source that emits a light beam having a far field pattern being elliptical in cross section;a collimator lens that converts the light beam from the light source into a substantially parallel light beam;a beam shaping element that performs beam shaping by changing a substantial aspect ratio of the far field pattern of the light beam from the collimator lens;light condensing means of condensing the light beam shaped by the beam shaping element on an optical information recording medium; andlight detecting means of detecting a light beam reflected at the optical information recording medium.wherein the beam shaping element makes the cross section of the light beam having been shaped close to a circle by compressing the light beam substantially in a direction of a major axis of the elliptical cross section of the far field pattern, and reflects the light beam from the collimator lens to the light condensing means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.