| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to stably execute a tracking servo by a push-pull method even with an optical recording medium previously recording reproduction-only signals. SOLUTION: The signals subjected to a prescribed modulation are recorded as the displacement in the track width direction of grooves G in the optical recording medium having the grooves G formed along recording tracks. The maximum amplitude quantity of the grooves displacement is specified to 6.25 to 31.25% of the track pitch at this time. On this optical recording medium, since the signals subjected to the prescribed modulation are recorded as the displacement in the track width direction of the grooves, the grooves G exist even in the information recording and reproducing region where the signals are previously recorded. Then, even if the optical recording medium has the information recording and reproducing region previously recorded with the signals, the tracking servo can be stably executed by the push-pull method. |
