Optical disk and apparatus for reading the same based upon the length of a mirror region

摘要

A high-density optical disk includes lands and grooves which are alternately formed to different depths around tracks of the optical disk and on each of the lands and grooves user information marks are formed. A mirror region is formed at a region of a change between a land and a groove, to guide a beam to sequentially access from a track to an adjacent next track, wherein the land and the groove are formed next to the mirror region, and a change between the land and the groove can be recognized by the detection of the mirror region. An apparatus for reading the high-density optical disk includes an optical detector to detect a beam reflected by the optical disk on which the mirror region is formed, and converting the detected beam into an electrical signal; a signal processor including a mirror region detector to process the electrical signal to detect the mirror region, and a tracking servo controller to receive the electrical signal from the mirror region detector and to make an appropriate tracking control on the tracks according to a change between the land and the groove.