| 摘要 |
PURPOSE:To reduce the size of the device and to improve the responsiveness of rotation control by providing a rotor consisting of a conductor and a coil, supplying electric power to an induction coil installed along the outer periphery of the rotator and rotating the optical disk. CONSTITUTION:The optical disk 1 is constituted by holding a permanent magnet 2 between two single-sided optical disks 3. The permanent magnet 2 is in a thin annular shape, its outer periphery is almost as large as the optical disk 3, and the permanent magnet is stucked and fixed on the disk 3 with an adhe sive 4. The magnet 2 operates as the rotor of an AC brushless motor when the optical disk 1 is loaded on the optical disk device. This optical disk 20 is set on the optical disk device and a current is supplied from a driving circuit 23 to the induction coil 22 to produce a magnetic field, so that the optical disk 20 rotates around the fulcrum of a disk support part 21 through the opera tion of the magnetic field of the permanent magnet 2 in the disk 20. |
