Patent · US Active

Optical disc, optical disc apparatus, and optical disc reproducing method

US7821908B2 · kind B2 · utility

4Cited by
5References
6Claims
0Family size

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Key dates

Filing dateNov 30, 2005
Grant dateOct 26, 2010
Priority date
Expiry dateSep 6, 2028

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2007/0013
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A single disc is configured to deal with both HD DVD information and DVD information. This invention has the following basic elements (1) a single-sided dual layer optical disc where a light transmission layer, a first recording layer accessed with a first laser beam, an space layer, and a second recording layer accessed with a second laser beam are arranged in that order in the direction in which a laser beam enters, (2) the areal recoding density of the second recording layer is three times or more that of the first recording layer, (3) information indicating that the second recording layer has been formed is formed in the first recording layer, and (4) information indicating that the first recording layer has been formed is formed in the second recording layer.

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