Piezoelectric Scanners

Abstract

Bimorph piezoelectric elements show relative large axial displacements at moderate voltages. Their response to voltage variations is very fast. The reproduceability of the displacement is practically limited only by the mechanical and electrical supplementary equipment. In combination with a deflection mirror linear scans or two -dimensional scan pattern can be generated. Fast scanning with good linearity and repeatability is possible, either in a resonant mode or in a random acces mode. However, the hysteresis of the piezoelectric material and the large capacitance of the elements impose some constraints on the applicability of the piezoelectric scanners.In the first part of the paper the properties of piezoelectric elements are discussed in view of scanner application; in the second part an experimental single mirror two -axis piezoelectric scanner is described. Some suggestions for future applications of piezoelectric scanners are made.