| 摘要 |
PURPOSE:To reduce the error and to increase the response speed by controlling the current of a linear motor provided to a spindle supporting a disk to shift the disk and therefore controlling automatically both focusing and tracking directions. CONSTITUTION:An armature 11 is set to a spindle 19 which supports a disk 8, and a yoke 12 and a coil 13 are provided at opposite positions of the side of a stator 18. Then a current is flowed to the coil 13 to drive a linear motor which shifts the disk 8 toward a track. In the same way, a linear motor is formed also in the focusing direction. The current flowed to the coil 13 is controlled by a tracking direction error signal. While the current flowed to a coil 18 of a linear motor in the focusing direction is controlled by a focusing direction error signal. Thus both focusing and tracking directions can be automatically controlled without shifting totally an objective lens nor an optical pickup. |
