Patent ID: 7969831
Filing Date: 2011-06-28
Classification: G11B

Abstract:
1. A servo control device for controlling a servo for printing on a label surface of an optical disc, the servo control device comprising: an optical pickup unit outputting a plurality of signals corresponding to a position of an object lens in response to light reflected from the label surface of the optical disc; an error signal generation unit outputting a signal by selecting one of the plurality of signals output from the optical pickup unit or combining at least two of the plurality of signals output from the optical pickup unit; a control unit adjusting the position of the object lens in response to the signal output from the error signal generation unit; and a direction sensor unit outputting a direction signal corresponding to a control direction of the object lens to the control unit in response to the plurality of signals output from the optical pickup unit, wherein the control unit adjusts the position of the object lens when the control direction corresponding to the direction signal is equal to a direction in which the object lens is intended to be adjusted.