| 摘要 |
PROBLEM TO BE SOLVED: To enable accurate recording and reproducing clocks to be generated by making constant the line density for the wave number regarding wobbling waveform of a track and forming a rotation angle mark indicating a prescribed rotation angle position of a disk. SOLUTION: Data are recorded while keeping constant line density(CLD), and the number of carrier waves of a wobbling group is assumed to CLD, further, a fine clock mark is added as CAV reference, and record and reproduction being more accurate are aimed at, and the wobbling period of a group is set. First, in adjacent tracks, the phase relation of a wobbling waveform is made so that a rotation angle position to be fixed relation exists. For example, when a rotation angle position of a start point of each rotation track is assumed to be 0 degree (the direction of 12 o'clock of a clock), the phase difference between adjacent tracks is made to have fixed relation at this position 0 degree. Further, a fine clock mark is added to a rotation angle position in fixed relation when phase difference is 0, 180, or 270 degrees. |
