RECORDING MEDIUM, ITS MANUFACTURING METHOD, AND MANUFACTURING METHOD OF ITS ORIGINAL PLATE

摘要

PROBLEM TO BE SOLVED: To eliminate inappropriate laser power due to uneven thickness of the recording/reproducing layer differing in inner and outer areas of the disk when recording or reproducing on a magneto-optical disk. SOLUTION: The grooves are made gradually deeper toward the outer side of the disk in a magneto-optical disk having spiral or concentric lands and grooves.