| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an adjustment method for a defocus amount and a spherical aberration correction amount which provides the best reproduced signal quality while performing a stable tracking control in a shorter period of time than before in a multilayer optical disk having a plurality of recording layers. <P>SOLUTION: Using an optical disk having three or more recording layers, a deviation amount of the depth in the focus direction is changed while tracking is in an off state and a spherical aberration correction amount is changed; search of a tilt of an edge line at which the amplitude of a larger tracking error signal can be acquired is executed in each of the recording layers; a prescribed function for the distance from an optical base point to the recording layer is created based on the acquired tilt of the edge line; and the tilt of the edge line is derived from the function also for the optical disk for which the tilt of the edge line is not actually measured. <P>COPYRIGHT: (C)2012,JPO&INPIT |
