OPTICAL RECORDING MEDIUM AND STAMPER THEREFOR

摘要

PURPOSE: To obtain an optical recording medium having uniform groove depth over the entire track area. CONSTITUTION: The optical recording medium has a track area comprising a track having diameter of about 86mm provided along a concentric or spiral groove only on the inside of 41.3mm radius wherein the tracking signal uniformity of the groove is 0.8 or above. The average height of protrusions for forming the groove from the innermost circumference to 39mm radius of the stamper is set in the range of 104-115% of the average height from 39mm radius or outside of the stamper.