POSITION CONTROL DEVICE, POSITION CONTROL METHOD

摘要

PROBLEM TO BE SOLVED: To correct a track pitch error caused when a distance between spots between a recording spot and a spot for an adjacent track servo does not coincide with a regulated track pith in a recording system adopting a tracking servo method based on the so-called ATS (adjacent track servo).SOLUTION: The so-called ATS+ for giving an integrated output of a recording layer tracking error signal obtained on the basis of reflected light of a spot for an adjacent track servo to a reference surface servo loop as an offset of the control target value thereof is adopted. By giving an offset to the recording layer tracking error signal in a servo control system as the ATS+, a pitch of a track formed by the recording spot is adjusted. This enables correction for making a track pitch coincide with a regulated pitch.