OPTICAL INFORMATION RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To improve tracking error signals and WCN(Wobble C/N) in a pit part without degrading jitters in pits. SOLUTION: Prepits 1 of 3200 Å depth are formed in a ROM region. An interpit groove 2 of 1800 Å depth having a constricted part in the joined part 2a with the prepit 1 is formed between one prepit 1 and another prepit 1. The constricted part is formed in the joined part 2a, being narrower than the other part (main part) of the interpit groove 2 (width in the main part × 1/2 <= width in the joined part) and shallower (depth in the main part × 1/2 <= depth in the joined part) so as to separate the prepit 1 from the main part of the interpit groove 2. By this structure, tracking error signals and WCN in the pit part can be improved.