Development and experimental analysis of piezoelectric optical scanner based on FEM and laser holography

Abstract

Piezoelectric optical scanner is developed for multi-coordinate control of optical laser beam. Such type of optomicro-mechanical systems can be used for accurate angular or linear deflection of optical elements in various optomechanical and optoelectronic systems. The operating principle of these devices is based on piezoelectric effect and on conversion of high-frequency multi-dimensional mechanical oscillations of piezoelectric vibration transducers into directional multi-coordinate motion of the optical elements in the measurement chain. The main distinctive feature of such optical piezoelectric scanners is the combination of high micrometer range resolution with a wide range of angular deflections of the scanning elements. The device consists of piezoelectric cylinder and a scanning element with three degrees of freedom. The control model of this device was derived using mixed finite element techniques. Special procedures were developed to obtain optimal configuration of discrete electrodes on the surface of piezoelectric cylinder. Dynamic model comprising matrix differential equation of the scanning element and FEM model of the piezoelectric actuator was used to derive adaptive control scheme. Experimental time averaging laser holography was used to validate the numerical model and to test the functionality of piezoelectric optical scanner.