A method and apparatus for realizing a stable focus jump operation even in
a case where a waveform of an S-curve of a focus error signal fluctuates
due to aberration due to fluctuation of a multilayer optical disk
substrate thickness or the level of the S-curve fluctuates due to
reflectance fluctuation are provided. A focus jump processing means (DSP
51) for performing a focus jump operation moving a laser spot among
recording layers of a multilayer optical disk 10 having a plurality of
recording layers corresponding to a record/reproduce operation for
recording data on the multilayer optical disk 10 or reproducing data
recorded on the multilayer optical disk 10 performs acceleration
processing for moving the objective lens mounted on an optical pick-up
from a certain recording layer of the multilayer optical disk to another
recording layer, waiting processing, and deceleration processing for
stopping the objective lens 34 and makes an impulse of the acceleration
pulse added for the movement of the objective lens 34 in the acceleration
processing larger than the deceleration pulse impulse stopping the
objective lens 34.