OPTICAL DISK/DRIVE HAVING SATELLITE BEAM FOR GENERATING RECTANGULAR PHASE ERROR SIGNAL FOR DETECTION OF RADIAL POSITION

摘要

PROBLEM TO BE SOLVED: To eliminate a DC(direct current) offset of a tracking error signal in an optical disk drive, and to also obtain a signal which directs a track movement direction in a radial direction of an optical disk.;SOLUTION: In the optical disk drive, a rectangular signal for canceling the DC offset from the tracking error signal and for determining the moving direction in the radial direction is generated, using signals from two satellite spots (212, 214). The two satellite spots generate a signal whose phase is changed by about 1/4 period from that of a main tracking error signal.;COPYRIGHT: (C)2002,JPO