Patent ID: 6503600
Filing Date: 2003-01-07
Classification: C03C,G11B,Y10S,Y10T

Abstract:
A magnetic recording medium having at least a thin-film magnetic layer on a glass substrate, wherein:said glass substrate has surface roughness Ra, Rmax, and Rq, where Ra is representative of a center-line mean roughness; Rmax is defined as a maximum height representative of a difference between a highest point and a lowest point, and Rq is representative of a root mean square roughness; the surface roughness measured by an interatomic force microscope is specified by Rmax &lE;15 nm, Ra&lE;1 nm, and Rq&lE;1.5 nm; and the ratio between the surface roughness Rmax and the surface roughness Ra is specified by 10&lE;Rmax/Ra&lE;30.