Patent ID: 6819638
Filing Date: 2004-11-16
Classification: G11B

Abstract:
A driving device for an optical storage medium, comprising:an optical pickup for reading out information from an information track on the optical storage medium, the optical pickup comprising (i) an irradiating device for irradiating a main-beam on the information track and two sub-beams at two different positions in a tangential direction of the optical storage medium and (ii) a photodetector device for detecting the main-beam and the two sub-beams reflected by the optical storage medium; a tracking error signal generator for generating a tracking error signal based on the two sub-beams detected by the photodetector; a tracking controller for controlling the optical pickup to follow the information track on the optical storage medium based on the tracking error signal generated by the tracking error signal generator; a defect detector for detecting a defect of the information caused by impediments existing on the optical storage medium based on the main-beam detected by the photodetector; a disturbance detector for detecting a magnitude of a disturbance of the tracking error signal when the defect of the information is detected by the defect detector; a correction signal generator for generating a correction signal corresponding to the magnitude of the disturbance of the tracking error signal detected by the disturbance detector; and a limiting unit for limiting an operation of the tracking controller in accordance with the correction signal generated by the correction signal generator.