Patent ID: 6229670
Filing Date: 2001-05-08
Classification: G11B

Abstract:
A magnetic data storage disk, comprising:a substrate body formed of a non-magnetizable material and having a substantially planar surface including an annular contact region adapted for surface engagement with a magnetic data transducing head during accelerations and decelerations of the substrate in a circumferential direction with respect to the transducing head; anda plurality of elongate ridge sections extended substantially circumferentially along the contact region, each ridge section having a circumferential length, a width in the radial direction and a height in an axial direction away from a nominal surface plane of the contact region;wherein each of the ridge sections is substantially uniform in height over substantially its entire length and is convex in a direction facing away from the nominal surface plane; andwherein adjacent ridge sections are spaced radially apart from one another by a radial pitch greater than the radial ridge section widths by at least a factor of ten, and the ridge sections have substantially the same height, thus to determine a substantially uniform surface roughness throughout the contact region.