DISK, DISK CARTRIDGE AND RECORDING/REPRODUCING DEVICE USING THE SAME

摘要

PROBLEM TO BE SOLVED: To suppress the wobbling of the surface of a disk against the rotary axis of the disk to a level without being hindered from recording/reproducing by making the minimum outside diameter of a turntable mounting surface on the disk of the disk having large outside dimension the relation larger than or equal to the minimum outside diameter of a turntable mounting surface on a disk having the small-sized outside diameter. SOLUTION: The rotational center of a disk 1 is made to coincide with a disk loading member 3 and a turntable 4 is brought into contact with a turntable becoming the reference surface on the disk. In order to ensure the contact, the disk 1 is mounted and held by a clamper 5 from the upper part of the disk for preventing the fall-off of the disk due to the high speed rotation of the disk. The minimum outside diameter Dmin of the turntable mounting surface on the disk of a standard disk is made to the relation of Dmin >= dmin to the minimum outside diameter dmin of the turntable mounting surface on the disk of a small-sized disk and then, the wobbling of surface is suppressed to a level without being hindered from recording/reproducing.