| 摘要 |
PURPOSE:To obtain the optical disk which has both of a read-only region and a write enable region within the same plane by forming the inner peripheral part as the read- only region and the outer peripheral part as the write enable region where recording and reproducing of information are executed and executing the rotation control of a mark length recording system and a mark position recording system at the same angular speed. CONSTITUTION:The inner peripheral part is formed as the read-only region 22 where the formation of the mark length recording system of a high recording density is easy. The write enable region 24 where the recording and reproducing of the information is executed by the mark position recording system suitable for the write enable region is disposed in the outer peripheral part. Namely, the decrease in the recording density of the mark position recording system is prevented by increasing the recording frequency at the time of recording the information in the writing region to two-fold the recording frequency of the read-only region 22, by which the recording density of the write enable region 24 is equal to the recording density of the read-only region 22. The recording of the recording in the two region is executed at the same rotating angular speed, by which the access speed is increased and the recording density is increased. The optical disk having the read-only region 22 and the write enable region 24 in one sheet of the disk substrate is obtd. in such a manner. |
