| 摘要 |
PROBLEM TO BE SOLVED: To effectively control a servomechanism by wobbling all land tracks and groove tracks, and forming wobbling of one of the groove tracks or land tracks different from phase with the other tracks, and forming wobbling of the other tracks in the same phase with each other. SOLUTION: A wobbling signal judging unit 128 judges that a track is a groove (or land) track in the case of detecting a wobbling signal from a 1st channel (CH1) but judges that the track is a land (or groove) track in the case of detecting the wobbling signal from a 2nd channel (CH2), and supplies a judgment signal presenting a groove track or a land signal to a controller 130. The controller controls a servomechanism part 132 according to the judgment signal, a groove (or land) wobbling signal from the 1st channel (CH1) through a 1st sample and hold circuit 124, and a land (or groove) wobbling signal from the 2nd channel (CH2). |
