Patent ID: 7746734
Filing Date: 2010-06-29
Classification: G11B

Abstract:
1. An optical disk apparatus, comprising: an optical head including a light source, a beam splitter which splits a beam from the light source into a plurality of beams, an objective lens which converges the plurality of beams split by the beam splitter into a plurality of optical spots on an optical disk, a photo-detector which detects the plurality of optical spots reflected from the optical disk, and an actuator which drives the objective lens in a radial direction of the optical disk; a thread motor which drives the optical head in the radial direction of the optical disk; a unit which generates a plurality of tracking spot signals from detection signals generated by detecting the plurality of optical spots; a unit which generates a tracking control signal for driving the actuator by mixing the plurality of tracking spot signals; and a mixing ratio changing unit which changes a mixing ratio of the plurality of tracking spot signals; wherein the mixing ratio changing unit determines the mixing ratio based on a measured amount of fluctuation of each of the tracking spot signals and a measured amount of decentering of the optical disk.