Design of a positioning device using piezo element and investigation of a simple compensation method

Demand for miniaturized and higher integration of various optical and electronic elements has increased along with the development and implementation of information technology in recent years. Holographic optical elements, which are attracting attention in the field of optical elements, can satisfy these demands. For this study, a prototype precision positioning device of a dual servo mechanism was designed and produced for microtrench processing. The coarse motion actuator incorporates a ball screw and a linear guide. Also, a laminated type piezoelectric actuator is used as a micro-motion actuator. A laser length measuring device was used to evaluate the precision positioning of the device. This study also examined a method for compensation of hysteresis by polynomial function fitted to displacement-voltage data and displacement characteristics of the piezoelectric element. Furthermore, for decreasing voltage, compensation by the lowest ordered second-order polynomial function must be preferred because no great difference in compensation performance was recognized in compensation by three different polynomials.