Single preloaded piezoelectric-ceramic-stack-actuator-based fast steering mirror with an ultrahigh natural frequency

To meet the requirements of the adaptive optics systems with high bandwidths and large excursion angles, we propose a fast steering mirror (FSM) with an ultrahigh natural frequency and a large angular range. The proposed FSM is driven by a preloaded piezoelectric ceramic stack actuator (PCSA), which has a higher shear stress limit in the working direction. We describe the structure of the preloading device and analyze the stiffness improvement of the preloaded PCSA. Then we introduce the structure of the proposed FSM and perform theoretical analysis based on the established static model and dynamical model. We also build an experimental setup of the proposed FSM. The experimental results show that the angular range of the proposed FSM is up to 8.4 mrad, and its first natural frequency is 6660 Hz, which surpass the performances of current FSMs.