MAGNETIC RECORDING MEDIUM GLASS SUBSTRATE AND METHOD OF PRODUCING THE SAME

摘要

A magnetic recording medium glass substrate is formed in disk shape and has on its surface a ridge-like texture (13) extending while describing a concentric circle. The width (W) of the texture (13) of low frequency component obtained by measuring a 10 mum square range by an inter atomic force microscope is 10 - 20 nm, the height (H) of the texture (13) is 2 - 10 nm, and the ratio (Rp / RMS) of the maximum hill height Rp to the root-mean-square roughness (RMS) of the texture (13) is not more than 15. The low frequency component of the texture has a high frequency component superposedly formed thereon, it being preferable that the width (W') of the texture of such high frequency component be 0.1 - 20 nm, and that its height (H') be 0.1 - 1 nm.