Optical disc reader having lens mounting with improved positioning control

摘要

An electro-optical device is able to follow the information structure (2) of a moving information carrier (3) with a radiation spot 17 in two directions, of which one extends in a plane perpendicular to the other. A lens system (5) is fixed in a lens mounting (9) which relative to a frame (4) may perform pivotal movements about a pivotal axis (10) parallel to the optical axis (6) of the lens system and translational movements along the pivotal axis (10) by means of electromagnetic actuator means (14, 13) which are symmetrically located with respect to the pivotal axis. The lens mounting (9) is of elongate form and its parts which are situated on opposite sides of the pivotal axis (11) have substantially the same mass and mass distribution.