| 摘要 |
PURPOSE:To eliminate the inclination of an objective lens by supporting an end part of a support arm for the objective lens on a guide shaft fixed to a slider in parallel to the optical axis of the lens so that it is rotatable and axially movable, and providing a rotating and axial moving means for the support arm. CONSTITUTION:When a current flows through a coil 25, the whole of the support arm 20 moves up and down along the guide shaft 22 in magnetic cooperation with a magnetic circuit 29. The objective lens 4 moves accurately in the optical- axis direction F without the inclination of the optical axis of the objective lens 4 to the optical axis, converging information readout laser light onto a disk 1. When a current flows through a coil 33, the support arm 20 rotates around the guide shaft 22 in magnetic cooperation with a magnetic circuit 34. The objective lens 4 moves in the track direction T of the disk 1 by the rotation. Consequently, the ability of the objective lens is displayed sufficiently without slanting the objective to the disk nor deteriorating characteristics of the objective and therefore an information reader. |
