Patent · US Expired

Information recording medium

US6744725B2 · kind B2 · utility

30Cited by
6References
1Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 12, 2003
Grant dateJun 1, 2004
Priority date
Expiry dateMay 12, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/21
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

In an information recording medium comprising at least a substrate, a recording layer, and a resin layer, the substrate is formed with at least a pit corresponding to a read only area 31 and a groove corresponding to a recording/reproducing area 32 without overlapping with each other. A reflectivity of the recording layer is specified to be more than 10%. The recording layer and the resin layer are continuously adhered over both the read only and recording/reproducing areas 31 and 32. The information recording medium is characterized in that both push-pull signal outputs T1 and T2, which are reproduced from the read only area 31 and the recording/reproducing area 32 respectively, are more than 0.1 and satisfy an inequality 1.5≧T1/T2≧0.5.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.