| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical disk device in which a control system of an objective lens drive device is stabilized and phase margin can be secured sufficiently. <P>SOLUTION: When the temperature of an objective lens holder 49 of the objective lens drive device 4 and an attachment part 50 fixing the objective lens holder 49 to a suspension 45 is changed, a resonance frequency of an elastic vibration mode of the objective lens drive device 4 is changed, and when discrepancy is caused between center frequencies of notch filters 21, 22 inserted to a servo loop of a control system of the objective lens drive device 4, the center frequencies of notch filters 21, 22 are made coincident with the resonance frequency of the elastic vibration mode changed automatically, the control system of the objective lens drive device 4 is stabilized and phase margin is secured sufficiently. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
