| 摘要 |
PROBLEM TO BE SOLVED: To reliably detect a defect and perform excellent correction by replacing a drive signal during the defect period with a correlating drive signal.SOLUTION: The optical disk apparatus comprises: a photodetector having areas which are obtained by dividing a light-receiving surface into a plurality of areas; a controlling device calculating detected signals from a plurality of areas, and generating a drive signal of a focus direction and a tracking direction; a defect determination device calculating a detected signal from each of the plurality of areas, generating a defect index signal which includes at least one absolute value of a difference signal among the detected signals, determining a defect according to the defect index signal, and generating a detected signal corresponding to the presence of the defect; a memory device storing an effective drive signal for one cycle of an optical disk; and a drive signal switcher selecting a drive signal from the controlling device when there is no defect, and selecting a drive signal from the memory device and providing the drive signal to a lens drive device when there is a defect.SELECTED DRAWING: Figure 1 |
