| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical pickup for performing highly reliable recording and reproduction without receiving the influence of interlayer crosstalk in a multilayer optical disk having a plurality of information recording layers, and to provide an optical disk medium. <P>SOLUTION: In the optical pickup compatible with tracking control by a DPP (Differential Push-Pull) system, a variation of a sub push-pull signal upon recording and reproduction to/from a multilayer disk medium having two or more information layers is limited to a prescribed range. RF signal variation is limited to a prescribed range in a multilayer disk having three or more information recording layers. <P>COPYRIGHT: (C)2009,JPO&INPIT |
