Original Publication Date: 1979-May-01
Included in the Prior Art Database: 2005-Feb-20
A magnetic recording disk is provided with controlled protrusions or asperities for use in evaluating and calibrating glide heads and glide height testers. The magnetic disk includes a substrate 11 and a magnetic coating 12 which is provided with at least two asperities 12a, 12b. Preferably, one asperity extends a predetermined amount such as 1 microinch above the desired glide height, while the other asperity projects 1 microinch below the desired glide height. Both asperities are located at the same radial distance R from the disk center and are spaced apart by a suitable angle Delta, such as 60 degrees.