| 摘要 |
PROBLEM TO BE SOLVED: To record data in high density both on the land track having a project shape and the groove track having a recessed shape and which have the same width and are alternately formed in helical form. SOLUTION: In this optical disk. the land track 16 and the groove track 17 having the same width are alternately formed in one revolution of a disk and the tracks 16, 17 are respectively divided into plural sectors and the sector 1 is divided into a first header area 2 and a data recording area 3. In the first header area 2, a synchronizing mark 11 and sector marks 20 to 23, 20' to 23' of sector addresses or the like are made to wobble in the left and the right around track centers 18, 19 several times, for example, two times in staggered shape with the half width of the track width. Moreover, this recording and reproducing device is made to detect the land track and the groove track. |
