| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a large amount of glass substrates for magnetic discs and magnetic discs having stable quality inexpensively by providing a manufacturing method of the glass substrate for the magnetic disc, which may simply polish the principal plane of the glass substrate to have a very smooth surface. <P>SOLUTION: In grinding using a planetary gear mechanism, a part of a glass disc 7 held on a carrier 13 is relatively moved to a lower surface plate 3 and an upper surface plate 4, and in that process, at least a part of the surface is passed on the outer peripheral side from the outer edges of the respective surface plates 3, 4. <P>COPYRIGHT: (C)2007,JPO&INPIT |
