Optical disk having pattern for tilt detection

摘要

An optical disk has a pattern for detecting an amount of a tilt of a disk. An optical disk on which a code train having a pit pattern or a mirror pattern is recorded on a concentrically or spirally formed track, wherein a tilt detection pattern (20, 22) having a predetermined code train is recorded at least in a partial area of the disk. Thus, since a pattern for tilt detection (20, 22) is recorded in a portion of a disk, a tilt of a disk can be detected by a common quadrant photodetector without an additional apparatus such as a photo coupler. <IMAGE>