| 摘要 |
<P>PROBLEM TO BE SOLVED: To remove an foreign material stuck to an objective lens in a disk unit with simple mechanism. <P>SOLUTION: A tracking error detecting part 331 detects a tracking error signal based on a reproduced signal read out from an optical disk. When the tracking error signal is in a state in which it exceeds the supremum or the lowest limit of the prescribed amplitude range, it is estimated that a foreign material is stuck to an objective lens as a main cause, a tilt control part 342 performs tilt operation for a tilt adjusting part 343 to remove the foreign material. Confliction between the objective lens and the optical disk by tilt operation is not caused even in a near field system by operating gap servo by a gap servo control part 322. <P>COPYRIGHT: (C)2007,JPO&INPIT |
