Optical actuator assembly with lens position sensor for recording or playback
AssigneeDiscovision Associates
InventorsKurt W. Getreuer, Leonardus J. Grassens
Life of this patent
Estimating the term…
Abstract
An apparatus for optical reading or recording information on an optical disc is rotatable about an axis of rotation. The apparatus includes a carriage, an objective lens, and an objective lens holder. The carriage has a center of mass. The carriage is movable relative to a frame along a path radial to the axis of rotation. The objective lens has an optical axis. The object lens is mounted to the objective holder so that the optical axis of the objective lens is within a first distance of intersecting the center of mass of the carriage. The holder is movable relative to the carriage so as to move the objective lens along its optical axis.
Claims24
An apparatus for controlling the position of a lens, the apparatus comprising:
- a carriage having a center of mass;
- an actuator having a center of mass, the actuator being suspended from the carriage at an initial position, and movable relative to the carriage;
- a lens disposed in the actuator, the lens defining an optical axis that substantially intersects the center of mass of the actuator and the center of mass of the carriage, suspensory forces acting on the actuator thereby being symmetric about the optical axis;
- and
- a focusing drive for the actuator, the focusing drive producing a plurality of focusing forces that are balanced and symmetric about the optical axis to displace the actuator relative to the carriage in a focusing direction so that movement produced by the plurality of focusing forces about the center of mass of the actuator is effectively absent, and forces reactive to the plurality of focusing forces are balanced and symmetric with respect to the optical axis to thereby produce only insubstantial movement about the center of mass of the actuator so that inertial forces acting on the actuator are balanced and symmetric about the optical axis.
An apparatus for controlling the position of a lens, comprising:
- a carriage having a center of mass;
- an actuator having a center of mass, the actuator being suspended from the carriage at an initial position, and movable relative to the carriage;
- a lens disposed in the actuator, the lens defining an optical axis that substantially intersects the center of mass of the actuator and the center of mass of the carriage, suspensory forces acting on the actuator thereby being symmetric about the optical axis;
- and
- a tracking drive for the actuator, the tracking drive producing a plurality of tracking forces that are balanced and symmetric about the optical axis to displace the actuator relative to the carriage in a tracking direction so that movement produced by the plurality of tracking forces about the center of mass of the actuator is effectively absent, and forces reactive to the plurality of tracking forces are effectively balanced and symmetric with respect to the optical axis to thereby produce only insubstantial movement about the center of mass of the actuator so that inertial forces acting on the actuator are balanced and symmetric about the optical axis.
Dependencies are inferred from the claim text.