Patent ID: 7145848

Claim:
An optical disk apparatus for recording and reproducing information to and from an optical disk, the optical disk apparatus comprising: an optical pickup for irradiating a light beam onto an optical disk surface for recording and reproducing the information to generate an analog reproduction signal therefrom; an A/D converter for converting the analog reproduction signal into a digital reproduction signal an adaptive equalizer for receiving the digital reproduction signal from the A/D converter and adaptively renewing a plurality of tap coefficients of a FIR filter; and an aberration control apparatus for minimizing an aberration contained in a spot of a light beam irradiated from the optical pickup onto the optical disk, wherein the aberration control apparatus comprises: an aberration detector for detecting the aberration of the light beam spot using the tap coefficients of the adaptive equalizer and generating an aberration detection signal in accordance with the detected aberration; an aberration correcting unit for correcting the aberration of the light beam spot; and a correction control unit for controlling the aberration correction of the aberration correcting unit in accordance with the aberration detection signal to minimize the aberration of the light beam spot, wherein the aberration detector is operable to detect the aberration by comparing at least one pair of the tap coefficients that are symmetrical with respect to a center position in time delay order thereof, and wherein a number of the plurality of the tap coefficients is odd, and the correction control unit is operable to control the aberration correction of the aberration correcting unit in a manner that at least a symmetrical pair of the tap coefficients are made substantially coincident with each other.