Analysis and experimentation of novel bi-directional photo-thermal micro-actuators

In this paper, a new type of thermal actuator based on photo-thermal expansion is introduced. The basic idea is using a high power laser beam to heat one arm of the actuator. Different temperatures of the two arms will lead to different thermal expansions, which result in lateral deflection at the connection free end. We first give a theoretical model and use experiment data to prove its validity. Applying the presented model we investigate the influence of the facular position and area on the lateral deflection. Photo-thermal actuators are in millimeter-scale size and easy to fabricate, and they can output micro-scale displacement. They use laser beam to transfer power avoiding the presence of electric current, so they can be applied in many special fields.