Patent ID: 6768705
Filing Date: 2004-07-27
Classification: G11B

Abstract:
An optical disk drive for use with an optical disk, comprising:a positioner for moving an objective lens in such a direction so as to move an optical spot across a data track formed on said optical disk, wherein said optical spot is caused by irradiating an optical beam through said objective lens onto said optical disk; a motor for carrying said positioner in said direction through transmission gearing, wherein said transmission gearing includes a pair of meshed gears, one of which is mounted to said positioner; a tracking error detector for receiving said optical beam reflected from said optical disk and for detecting a track error signal representing a degree of positional coincidence between said optical spot and said data track; an index pulse generating means for generating an index signal indicating at least one revolution of said optical disk; an eccentric displacement data analyzing unit for storing eccentric displacement data indicating a magnitude and a phase angle of said optical disk eccentricity, wherein said eccentric displacement data is produced from a combination of said track error signal and said index signal; and wherein said motor is controlled by a driving signal produced from said eccentric displacement data while said data track is being tracked by said optical beam; and further wherein said optical disk drive further includes: an actuator mounted upon said positioner, said actuator being capable of moving said objective lens across a data track on said optical disk as well as perpendicular to said optical disk; a position detecting means for detecting a position signal indicating a distance between said positioner and said actuator in said direction; a compensating signal generating means for generating a low-passed signal from said position-signal; and wherein said motor is controlled by said driving signal combined with said low-passed signal.