OPTICAL DISK MASTER DISK, EXPOSURE DEVICE FOR MASTER DISK, OPTICAL DISK AND PRE-FORMAT INFORMATION DEMODULATION CIRCUIT

摘要

PROBLEM TO BE SOLVED: To realize an optical disk master disk of L/G recording system recording address information as pre-format information. SOLUTION: A land 1 and a groove 2 of which land width Wl and groove width Wg are equal to each other, are arranged alternately in the radial direction, and the groove 2 is wobbled to the land 1 side by 1/2 of a track width. Thus, the address information is recorded as the pre-format information.