Optical pick-up aberration correcting mirror, aberration correcting method and optical pick-up
US7369482B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2004 |
| Grant date | May 6, 2008 |
| Priority date | — |
| Expiry date | May 13, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/1362
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
It is an object of the invention to provide an aberration correcting mirror which has a small size, power saving, a low voltage, a low price and high precision. In particular, it is an object to provide a practical mirror for correcting a spherical aberration.The invention provides an aberration correcting mirror constituted by a substrate, a piezoelectric unit, a pair of electrode films interposing the piezoelectric unit therebetween, an elastic unit and an optical reflective film, wherein the substrate has a cavity portion which is schematically symmetrical about an optical axis, each of the pair of electrode films is divided into at least two parts including a first electrode and a second electrode, the first electrode being schematically symmetrical about the optical axis and the second electrode being provided to surround the first electrode, and such an electric potential as to set the directions of electric fields in the piezoelectric unit to be reverse to each other is applied to the first electrode and the second electrode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.