Method for recording and reproducing information using an optical memory
US5438561A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 1994 |
| Grant date | Aug 1, 1995 |
| Priority date | — |
| Expiry date | Oct 26, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/2595
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for recording and reproducing information using an optical memory device being constituted by a transparent substrate, a recording film formed on the substrate and made of a resin containing a photochromic material dispersed therein, the photochromic material being capable of reversibly changing its state from achromatic to chromatic and absorbing light of at least 780 nm wavelength in the chromatic state, and a reflecting film formed on the recording film for reflecting light, the method including the steps of: applying a visible light beam of a long wavelength onto the optical memory device to turn said recording film into the achromatic state for initialization, applying thereafter a visible light beam of a short wavelength onto the optical memory device to turn the recording film into the chromatic state in accordance with binary-coded data of information for recording the information, and applying another visible light beam of a long wavelength having a light intensity lower than that of the visible light beam for initialization onto the optical memory device for reproducing the information having been recorded therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.