Investigation Of Electrowetting-based Liquid Prism

Beam steering has been widely used in many fields, such as telecommunications, laserdetection, and free-space optical communications. As for the traditional mechanical beam steeringapproach, it uses a mechanical device to control the direction of the optical axis thus changing thebeam direction, a bulky motorized mechanical system will not only increase the system complexity,volume; but also limited mechanical switching speed and less system reliability. Theelectrowetting-based liquid optical prism have the advantages of a simple fabrication process, largescale apertures, fast switching speed and wide contact angle change with low voltages. This paperpresents the electrowetting-based "double" and "triple" liquid optical prism system, and has donethe following research work:Firstly, this paper introduces the research background of beam steering technique andelectrowetting on dielectric. Young-Lippmann equation is deduced base on Thermodynamics andelectrochemical model, the problem of electrowetting on dielectric is discussed.Secondly, the electrowetting-based "double" and "triple" liquid optical prism is designed andfabricated, by analyzing the principle of liquid optical prism. The experimental results show that,the liquid dielectric optical prism based on electrowetting effect can control of the beam de flection,the maximum beam liquid optical prism angle is calculated, the influence of materials, interfacialtension, and AC/DC voltage on the device performance is also analyzed. It provides a reference forfurther application of liquid optical prismThirdly, electrowetting liquid optical prism model based software COMSOL Multiphysics4.3has been established. The influence of voltage on velocity fields of the internal fluid motion and theshape of liquid interface are analyzed, and the effect of dynamic viscosity on the prism’s responsetime and stability are also discussed. Meanwhile, the best response time is presented.The paper summaries the research contents and the achievements, summarize the unfinishedwork and direction for future work is summarized and prospected.