| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce interlayer crosstalk in an optical recording medium including three or more information recording layers, especially interlayer crosstalk between information recording layers not adjacent to each other. <P>SOLUTION: The optical recording medium is provided with: a substrate 11; a protective layer 19; an L0 layer 20, an L1 layer 30 and an L2 layer 40 which are disposed between the protective layer 19 and the substrate 11; a transparent intermediate layer 12 disposed between the L0 layer 20 and the L1 layer 30; and a transparent intermediate layer L3 disposed between the L1 30 and the L2 layer 40. A thickness Da of the transparent intermediate layer 12 is different from a thickness Db of the transparent intermediate layer 13. Thus, when data is reproduced from the L0 layer 20, a beam spot of a laser beam L' reflected from the L1 layer 30 is not focused on the L2 layer 40, and hence interlayer crosstalk from the L2 layer 40 to the L0 layer 20 is effectively reduced. <P>COPYRIGHT: (C)2009,JPO&INPIT |
