Patent ID: 7736770

Claim:
A method for manufacturing a substrate for information recording media, the method comprising: surface polishing at least one surface of a starting material glass plate, wherein said surface polishing consists essentially of precision polishing using fine abrasive grains having a predetermined grain diameter, wherein the starting material glass plate has a plurality of types of surface waviness before the surface polishing classified by wavelength band formed in a fashion superimposed on one another on at least one surface thereof; wherein a long-wavelength waviness before the surface polishing for which the wavelength band is highest is 0.4 nm to 6 nm, a short-wavelength waviness before the surface polishing for which the wavelength band is lowest is 0.1 nm to 0.7 nm, and a medium-wavelength waviness before the surface polishing for which the wavelength band is intermediate is 0.25 nm to 2 nm; wherein a difference between a thickness of the starting material glass plate before the surface polishing and a thickness of the starting material glass plate after the surface polishing is no more than 15 μm; wherein the starting material glass plate has another plurality of types of surface waviness after the surface polishing classified by wavelength band formed in a fashion superimposed on one another on at least one surface thereof; and wherein a final long-wavelength waviness after the surface polishing for which the wavelength band is highest is 0.3 nm to 1.2 nm, a final short-wavelength waviness after the surface polishing for which the wavelength band is lowest is 0.1 nm to 0.6 nm, and a final medium-wavelength waviness after the surface polishing for which the wavelength band is intermediate is 0.2 nm to 0.9 nm.