| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that optical discs having warpage are produced by pressure supplied in a plastic process when conventional simply flat optical discs are produced and the discs having warpage are rejected in a quality management step and to effectively reduce the number of the discs rejected in the quality management step so that more satisfactory products are produced at lower costs. <P>SOLUTION: An optical disc substrate includes an annular substrate and a protrusion. The annular substrate has an inner supporting portion and an outer recording portion having a recording surface. The protrusion overlaying the supporting portion has a plurality of indentations on its outer periphery, wherein the lapped thickness of the protrusion over the supporting portion is greater than the thickness of the recording portion. An optical disc, wherein a paint layer for recording data is coated on the recording surface of the disc substrate, is also disclosed. <P>COPYRIGHT: (C)2007,JPO&INPIT |
