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

An objective lens actuator for use in optically writing or reading information on a disklike recording medium, said actuator comprising:

• a base;
• a stationary member mounted on said base;
• a movable member, including a lens holder and an objective lens held by said lens holder, movably mounted for movement relative to said base in a radial direction parallel to a face of the recording medium and in an optical axis direction perpendicular to the face of the recording medium;
• a pair of leaf springs, each of which is of a substantially rectangular frame shape having a pair of first opposing edge portions and a pair of second opposing edge portions, said pairs of first and second opposing edge portions defining therebetween, for each of said leaf springs, a single central opening, and said pairs of first opposing edge portions of said pair of leaf springs constituting four elastic members, respectively;
• a drive means for driving said movable member in the radial direction and in the optical axis direction;
• wherein said elastic members each have a first end fixed to said stationary member and a second end fixed to said movable member so as to longitudinally extend substantially in parallel with each other and substantially perpendicularly to the radial direction and the optical axis direction;
• wherein said elastic members are fixed to said stationary member by projections formed on said stationary member, said projections formed on said stationary member extending through said single central openings of said leaf springs, respectively;
• and
• said elastic members are fixed to said movable member by projections formed on said movable member, said projections formed on said movable member extending through said single central openings of said leaf springs, respectively.