OPTICAL DISK DEVICE

摘要

This optical disk device divides the cross section of a return beam from a disk into a plurality of regions, and creates a tracking error signal by performing a calculation so as to increase the weighting of the light intensity of the regions, from among the divided regions, positioned at the circumference of an ellipse with a good radial symmetry. Furthermore, the device forms a lens-shift detection signal and cancels the lens-shift detection signal on the basis of a push-pull signal.