Disc-shaped recording medium and disc driving system

摘要

A disc-shaped recording medium for which information signals are recorded and/or reproduced in a state in which a rotating recording and/or reproducing head is floated a pre-set distance from a signal recording region carrying surface of the disc-shaped recording medium. The disc-shaped recording medium has an area radially outside of the outer perimeter of center opening by at least 0.1 mm clamped by a clamp mechanism. This area is coplanar as each surface of the disc-shaped recording medium carrying the signal recording region. It is possible in this manner to prevent eccentricity of the rotating disc-shaped recording medium and consequent collision of the recording and/or reproducing head against the disc-shaped recording medium.