| 摘要 |
PURPOSE:To obtain a track error signal detecting method not affected by deflection or warp of an optical disk by correcting a difference of a two-split photodetector due to the tilt of the optical disk. CONSTITUTION:A track width modulation section (a) whose track width varies with a prescribed period of a higher frequency than a conventional information signal frequency respectively at each prescribed angle based on the center of the optical disk or at each prescribed pitch of a track 1 is provided. Then, the reflected light of a laser light radiated onto the track 1 or the transmitted light 2 is received respectively at the split areas of the photodetector 3 and a track error signal is detected based on a 1st error signal taking a difference of the output signal of each area through a low pass filter 4 and a 2nd error signal detecting each output signal through a high pass filter 5 and taking a difference. Thus, the track error signal detection method is obtained without being affected by the deflection or warp of the optical disk. |
