OPTICAL DISK,申请号JP19880228620-传众专利搜索

OPTICAL DISK

申请公布号：JPH0278035(A)

申请号：JP19880228620

申请日期：1988.09.14

申请公布日期：1990.03.19

申请人：

HITACHI LTD

发明人：MORIYA KOICHI;TOKUJIYUKU NOBUHIRO;IKEDA HIROAKI

分类号：B41M5/26;G11B7/24

主分类号：B41M5/26

摘要：PURPOSE:To decrease the deformation of a substrate due to the thermal diffusion of a recording film by forming thin films at different light absorbing ratios at the internal peripheral part and external peripheral part of the substrate. CONSTITUTION:For a PC substrate by means of injection molding, strain larger than that in the other part remains in the internal peripheral part of the substrate, it is released by heating the substrate, and it appears as the deformation of the substrate. There, the recording film is formed only in the area where a tracking signal exists in the substrate 1, namely, only in an area 2 where information can be reproduced. Further, the recording film is not formed in the area in the internal peripheral part, and a layer 3 having small light absorption is formed. Thus, the remaining strain in the internal pheripheral part is decreased, and the deformation of the substrate can be suppressed.