Photostrictive actuators

Photostrictive materials, exhibiting light induced strain, are of interest for future generation wireless remote control photo-actuators, micro-actuators, and micro-sensors applications. (Pb, La)(Zr, Ti) O₃ (PLZT) ceramics doped with WO₃ exhibit large photostriction under uniform illumination of near-ultraviolet light. Using a bimorph configuration, a photo-driven relay and a micro walking device have been demonstrated. However, for the fabrication of these devices, materials exhibiting higher photovoltaic effect and higher response speed must be developed. The present paper reviews a new theoretical model for photovoltaic effect first, then enhanced performance photostrictive materials through sample surface characteristics, finally its potential future applications.