| 摘要 |
<P>PROBLEM TO BE SOLVED: To record and reproduce data with stable interlayer jump using an objective lens having a numerical aperture of 0.8 or more for a multilayer optical disk provided with at least first and second recording layers. <P>SOLUTION: In an optical disk device provided with an optical pickup that includes a convergent optical system including an objective lens for converging a light beam emitted from a laser beam source to a microspot on the recording layer of an optical disk and an aberration correction optical system for controlling the spherical aberration of the convergent optical system, an operation of changing the correction quantity of the spherical aberration from a value adequate for a first recording layer to a prescribed value is started before an operation of moving the focal position of the microspot from the first recording layer to a second recording layer is completed. This allows focus control to be stably performed with respect to the second recording layer in which focusing is newly performed in a state that the spherical aberration has already been carried out, thereby, preventing the focus control from failing due to an unsuccessful interlayer jump. <P>COPYRIGHT: (C)2009,JPO&INPIT |
