Objective lens actuator having frame-shaped leaf springs for minimizing focusing and tracking errors

摘要

An objective lens actuator in which an objective lens of a device for optically writing or reading information on a disklike recording medium is driven in a radial direction parallel to a face of the recording medium and in a direction of an optical axis perpendicular to the face of the recording medium. The actuator includes a movable member which includes the objective lens and a lens holder for holding the objective lens; a stationary member; and a pair of leaf springs each of which is of a shape of a substantially rectangular frame having a pair of first opposed edge portions and a pair of second opposed edge portions such that the first opposed edge portions of the leaf springs act as four elastic members, respectively. The elastic members each have one end fixed to the lens holder and the other end fixed to the stationary member so as to longitudinally extend substantially in parallel with each other an substantially perpendicularly to the radial direction and the direction of the optical axis. A drive member is provided for driving the movable member in the radial direction and in the direction of the optical axis, and a base is provided to support the stationary member.