Optical information recording medium comprising a first layer having a phase that is reversibly changeable and a second information layer having a phase that is reversibly changeable
US6456584B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1999 |
| Grant date | Sep 24, 2002 |
| Priority date | — |
| Expiry date | May 14, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2007/25713
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A multi-layer optical information recording medium has a first information layer located at the incident side for a laser beam and another information layer at the back thereof. Thus, it has a large capacity. A relationship that R1a<R1c and R2a<R2c holds for the reflectances R1a and R1c of the information layer in the in a recorded portion and in a non-recorded portion, and the reflectances R2a and R2c of the information layer in a recorded portion and in a non-recorded portion. A relationship that A1a<A1c holds between the absorptances A1c and A1a of the first information layer in the crystalline state and in the amorphous state, similarly, a relationship A2a<A2c holds between absorptances A2c and A2a of the second information layer in the crystalline state and in the amorphous state. Thus, signals can be written to the recording medium at a fast speed and at high sensitivity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.