Optical disk drive with use of sampled preceding focus or tracking error signal in response to detection of spiked noise or offset

摘要

By making the servo system insensitive to the spiked noise having high frequency components, a stable focus control and/or tracking control of an optical disk drive is realized. A digital signal processor is provided for sampling an output of an error detecting circuit for detecting an amount of deviation of control with a constant period to perform a phase compensation therefor and outputting a drive instruction value for the focus or track control on the basis of a signal sampled in a just preceding period when an error signal value sampled in a current period is larger than the error signal value sampled in the just preceding period.