Techniques for writing and reading data on an optical disk which include formation of holographic optical gratings in plural locations on the optical disk
US6898167B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 2001 |
| Grant date | May 24, 2005 |
| Priority date | — |
| Expiry date | Apr 15, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/28
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical memory for storing and/or reading data on an optical disk. The optical disk incorporates a material in which holographic gratings can be created, and subsequently detected, at plural locations within the disk by an electro-optical head. Creation and detection of holographic gratings with variable diffraction efficiency is possible with the electro-optical head. Multiple holographic gratings can also be created at each one of the plural locations via a beam of light which has a different wavelength or point of focus. These data elements can be read by the electro-optical head using a beam of light sequentially varied in wavelength or point of focus to correspond to the multiple holographic gratings to be recorded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.