Optical recording medium, optical recording method, optical reproducing method, optical recording apparatus, and optical reproducing apparatus
US7719953B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 2005 |
| Grant date | May 18, 2010 |
| Priority date | — |
| Expiry date | Mar 14, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/26
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A substrate in which a minute ruggedness structure including columnar projections is formed in a track shape is prepared. The pitch of the columnar projections of the ruggedness structure is set such that a plurality of the columnar projections is within a beam spot. A flat portion is disposed between adjacent tracks. A reflecting layer is formed on the substrate. The flat portion becomes a mirror surface because of the formation of the reflecting layer. The reflectance of the ruggedness structure becomes significantly lower than the reflectance of the flat portion. When the ruggedness structure is irradiated with high-power laser light, a portion of the ruggedness structure is raised to a reflecting layer side and flattened. At this time, reflectance of the raised portion becomes higher than reflectance of a non-raised portion. When a track including the ruggedness structure is irradiated with high-power pulse laser light, signal recording based on a change in reflectance is possible.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.