OPTICAL DISK AND OPTICAL DISK DRIVE DEVICE

摘要

An optical disc having a plurality of substantially concentrically extending tracks has a plurality of segments each including a servo area ARs and a data area ARd. In the servo area ARs, having servo pits representing the servo information to the disc drive, there are recorded discrimination marks SGM, ADM, STM1 and STM2. These discrimination marks SGM, ADM, STM1 and STM2 afford the segment-discriminating information depending on the recording position in the servo area ARs.