| 摘要 |
<p>PROBLEM TO BE SOLVED: To make it possible to perform an exact tracking servo control of all shallow/deep group system optical disks. SOLUTION: A tracking servo control is performed by judging whether an optical disk is a shallow or a deep group system, and correcting the phase of a tracking error signal according to this judgement result. The tracking device is provided with an optical signal detecting part 30 for detecting a tracking error signal from an optical disk, a group system judging part 32 for analyzing the tracking error signal from the optical signal detecting part 30, judging the group system, and generating control signals C1, C2 responding thereto, a phase correction means 34 for correcting the phase of the tracking error signal from the optical signal detecting part 30 according to the control signals from the group system judging part 32, and a tracking servo part 36 for controlling a beam spot for an exact tracking by using the phase-corrected tracking error signal.</p> |
