| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multilayer type optical disk having a structure capable of surely distinguishing signal surfaces of each layer in a multilayer type optical disk. <P>SOLUTION: In the multilayer type optical disk 1A wherein recordable or reproducible signal surfaces are formed in a multilayer state and groove tracks 3 each spirally or concentrically formed on each signal surface of each layer are wobbled, the groove tracks 3 are wobbled by a prescribed clock frequency for obtaining a wobble signal WBLc for clock and wobbled by single frequency lower than the prescribed clock frequency and different for every layer for obtaining wobble signals WBL1, WBL2 and WBL3 for discriminating the layer for every layer. <P>COPYRIGHT: (C)2009,JPO&INPIT |
