| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce access time in an optical disk where information layers based on a plurality of different optical disk specifications are multi-layered. <P>SOLUTION: In the optical disk where information layers based on the plurality of different optical disk specifications are multi-layered on a single disk, a type of a given information layer is recorded in another information layer. An optical disk drive based on the plurality of optical disk specifications selects a method for generating a tracking error signal on the basis of the information recorded in another information layer upon reading and writing, and reduces the access time. <P>COPYRIGHT: (C)2007,JPO&INPIT |
