Patent ID: 7257056
Filing Date: 2007-08-14
Classification: G11B

Abstract:
1. An optical pickup tracking controller comprising: sum generation means for generating a sum signal of light detection electric signals of a plurality of light reception parts; phase comparison means for comparing phases of the sum signal and each of the light detection electric signals to obtain a plurality of comparison results respectively corresponding to the light detection electric signals and outputting, based on the comparison results, a plurality of phase lead signals, which respectively correspond to the light detection electric signals, and a plurality of phase lag signals, which respectively correspond to the light detection electric signals; phase sum generation means for calculating sums based on the phase lead signals and the phase lag signals and outputting a tracking control signal based on the sums; and phase difference generation means for calculating phase difference signals of differences between the phase lead signals and the phase lag signals wherein the optical pickup tracking controller performs tracking servo control based on the phase difference signals.