PURPOSE:To shorten the time needed for the start through the end of a track follow-up action by performing both the adjusting and cross-tracking actions at a time for the rough seeking control. CONSTITUTION:The output of a fine seeking control driver 22 drives a fine shift mechanism 28 set on a rough shift mechanism 8 via switches 24 and 26 and according to the cross-track deviation 226, i.e., the value of a cross-track counter 12. Thus the mechanism 28 is shifted at a high speed up to the target of the mechanism 8. When a light spot reaches the target of the mechanism 8 and the deviation 226 is equal to zero, the connection between switches 7 and 24 is switched and both rough and fine follow-up control signals 238 and 240 of a track follow-up control driver 32 are applied to the mechanisms 8 and 28 respectively. Thus the track follow-up control is started. Then an information reading circuit reads out the track address of the place where the track follow-up control is started. Then the mechanism 28 is driven and shifted up to the target track by the shift amount 242 from the target track, the track jump control signal 244 and the track jump switching signal.
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