Patent ID: 7936661
Filing Date: 2011-05-03
Classification: G11B,Y10T

Abstract:
1. An optical information recording medium comprising a disc-like light-transmissive substrate having a surface provided with a spiral groove having a wobble and a land between adjacent segments of the groove, a light-absorbing layer disposed on the surface of the light-transmissive substrate, and a light reflection layer disposed on the light-absorbing layer, wherein the groove has a depth Ds of about 140 nm≦Ds≦155 nm; the light-absorbing layer has a recess with a depth Dd of about 95 nm≦Dd≦105 nm in the groove; the light-absorbing layer has a thickness Dg of about 102 nm≦Dg≦106 nm in the groove; and a push-pull signal derived from the optical recording medium before recording has a value of 0.241 or higher but about 0.3 or less; said optical information recording medium being such that only a recording apparatus made specifically for the optical information recording medium is capable of recording data on the medium and a general recording/reproducing apparatus is capable of reading out the data from the medium.