Non-tilting plate actuator for use in a micropositioning device

摘要

A non-tilting positioner for a micropositioning device constructed of piezoelectric plate actuators each arranged with a pair of opposed parallel edges respectively coupled to first and second elements. A first surface of each plate is divided into quadrants, with first electrodes in each of the quadrants. At least one second electrode is provided on the opposed surface. Electric voltages are applied to the first and second electrodes with appropriate polarities so as to generate an electric field through the thickness of the plate which is of a first polarity in a first pair of diagonally opposite quadrants and is of the opposite polarity in the second pair of diagonally opposite quadrants. Movement along a line parallel to the plane of the plate is thereby effected. Movement in a third orthogonal direction can also.be attained by selecting an appropriate electrode pattern. A compact design with double the range is attained by providing at least two of the aforedescribed actuators which are arranged with their plates in parallel or coplanar relation to each other, with a rigid intermediate element being coupled to one end of each of the actuator plates. This "doubling back" of the plates is inherently thermally compensated and eliminates parasitic vertical motion associated with the desired horizontal motion.