| 摘要 |
PURPOSE:To miniaturize a device, to reduce an occupant space, and to reduce a cost by fixing a rotary member having a phase contrast plate on a ball bearing. CONSTITUTION:One pickup can be used for a magneto-optical disk also for a DRAW (direct-read-after-write) type disk by switching the direction of the optical axis of the phase contrast plate 20 by rotating, and in addition to that, the direction of the optical axis of the phase contrast plate 20 can be switched by utilizing and fixing the phase contrast plate 20 on the outer ring or the inner ring of the ball bearing 30. In such a way, the ball bearing 30 can be arranged in the neighborhood of the optical axis of the pickup, and to form the constitution of an actuator for the switching of the phase contrast plate 20 compactly, therefore, the optical pickup of combination type can be formed compactly. |
