Hologram recording medium and hologram record-reproduction device
US7639586B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 15, 2005 |
| Grant date | Dec 29, 2009 |
| Priority date | — |
| Expiry date | Oct 18, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/127
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A disk-type hologram recording medium and a hologram recording and reproduction device utilizing such a recording medium are provided. The hologram recording and reproduction device includes a spatial optical modulator provided with a plurality of optical elements arranged in a grid-like form. These optical elements are divided into groups each associated with 1 bit of data for performing required light modulation. Thus, a special pattern exhibiting a greater S/N margin for 1 bit can be recorded in the recoding medium. During data recording or data reproduction, the special pattern is read from the recording medium, and based on the retrieved special pattern, fine adjustment by servo control is conducted for adjustment of tilting or focusing of the recording medium and for adjustment of the wavelength of the light emitted from the light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.