| abstract |
A glass substrate for perpendicular magnetic recording, having a surface with an average surface roughness of 2.0 Å or less and surface height variations of 1 Å or less with wavelengths in the range of 0.05 mm-0.5 mm in both radial and circumferential directions, is produced by rotating a glass substrate, supplying polishing slurry containing a specified amount of abrading particles of artificial diamond on its surface, pressing a polishing tape on the surface and causing this polishing tape to travel in a direction opposite to the direction of rotation of the glass substrate. |