Stress-modulated tilt actuator for tunable optical prisms

A tunable optical prism MOEMS based on the deformation of a liquid droplet is presented. An aluminum-nitride membrane is tilted by a novel type of thermo-mechanical actuator. The actuatio nprinciple is based on a thermo-mechanical modulation of the intrinsic stress in aluminum-nitride beams. Based on an analytical model, the key parameters of the actuator are optimized.

Furthermore, the influence of the intrinsic stress on the actuator properties is investigated. These dependencies and the model are verified by mechanical characterization of samples. Operation in air and with ambient fluid has been confirmed. An image shift of 30 μm is found in a microscopic setup which corresponds to 19 % of the field of view.