Optical head including an active polymer film for switching voltage during recording and reproducing processes
US7113472B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2002 |
| Grant date | Sep 26, 2006 |
| Priority date | — |
| Expiry date | Nov 11, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2203/07
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical head for recording or reproducing a signal with respect to an optical recording medium, which includes an optical element disposed between a light source and an optical recording medium. The optical element has an optically active polymer film in which an optical rotation property changes with respect to an applied voltage, a pair of conductive transparent thin films for applying a voltage to the optically active polymer film, and a transmittance polarization anisotropic part having a different transmittance with respect to a polarization direction, which is disposed on one of the conductive transparent thin films. By changing the applied voltage to the optically active polymer film, a light quantity of a linearly polarized light transmitted through the optical element can be changed substantially instantaneously. Therefore, the power of light reaching the optical recording medium can be switched substantially instantaneously at the time when switched between recording and reproduction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.