Patent ID: 6134198
Filing Date: 2000-10-17
Classification: G11B

Abstract:
A tracking error signal calculation circuit for calculating a tracking error signal in an optical disc apparatus having a light receiving means for outputting first and second received light detection signals from regions located at the two sides of the center of a track of a disc-like recording medium, said circuit comprising:a first calculation circuit for detecting a peak of the first received light detection signal from the light receiving means and subtracting a signal obtained by multiplying a first coefficient with the peak from the first received light detection signal to calculate a first calculation signal;a first coefficient changing circuit for changing the first coefficient, wherein the first coefficient changing circuit has a circuit for changing the first coefficient depending upon a frequency of the first received light detection signal;a second calculation circuit for detecting a peak of the second received light detection signal from the light receiving means and subtracting a signal obtained by multiplying a second coefficient with the peak from the second received light detection signal to calculate a second calculation signal; anda third calculation circuit for subtracting the second calculation signal from the first calculation signal to calculate the tracking error signal.