Patent ID: 6693861
Filing Date: 2004-02-17
Classification: G11B

Abstract:
A method for servo control of an optical disk reproducing/recording device, comprising the steps of:(a) detecting a distance between the center of an objective lens and an optical axis, wherein the distance is obtained by accumulating an operating signal that is used to operate an actuator relative to a current position of the objective lens; (b) checking whether the detected distance exceeds a predetermined range; and (c) changing the magnitude of a drive signal by a microstep depending upon the check result and applying the drive signal to a sled motor for moving an optical pickup containing the objective lens, wherein the operating signal includes T+ and Tâˆ’ signals applied to an actuating coil and in said step (a), the distance is obtained by accumulating difference values between the T+ and Tâˆ’ signals.