Optical information recording medium and method of marking BCA (burst cutting area) into the same
US7843796B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 15, 2007 |
| Grant date | Nov 30, 2010 |
| Priority date | — |
| Expiry date | Oct 16, 2028 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/259
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical information recording medium includes a read-only information recording portion, and a BCA (Burst Cutting Area) portion formed by laser marking. A reflective film on an information recording surface of the read-only information recording portion and a reflective film on the BCA portion are formed of the same material. The reflective film includes Ag as a main component, and at least one of Nd and Gd, and at least one of Sn and In as components; the reflective film including at least one of Nd and Gd of 0.1 atom % or more and 3.0 atom % or less in total and at least one of Sn and In of 3 atom % or more and 12 atom % or less in total. Recorded information is reproduced from the information recording surface of the read-only information recording portion and a BCA signal is reproduced from the BCA portion, using blue-violet laser reproducing light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.