Patent ID: 7301859
Filing Date: 2007-11-27
Classification: G11B

Abstract:
1. A track error detection device including an element for receiving light reflected from a data recording surface of a recording medium, a divided light spot received in the element in tangential and radial directions, and a track error signal detected using signals A, B, C and D that correspond to quantities of light received in respective divided parts, the device comprising: an equalizing unit equalizing the inputted signals A, B, C and D to a level; a comparison unit quantizing the equalized signals A, B, C and D; a phase shifting unit removing phase offsets among the quantized signals A, B, C and D, in accordance with control signals; a first control signal for shifting phases of the quantized signals A and C; and a second control signal for shifting phases of the quantized signals B and D to the phase shifting unit, wherein the phase shifting unit removes the phase offset between the quantized signals A and B and the phase offset between the quantized signals C and D based on the first and second control signals.