Design And Performance Analysis Of Double Zoom Liquid Lens Based On Electrowetting

Variable-focus lens is the key component in many optical productions such as camera, moviecamera, telescope and so on. Conventional tunable-focus lens usually consists of two or morefixed-focus lenses, and mechanical devices such as electric motors, gears are used to adjust thelenses relative location to change the focal length. Due to the existing of mechanical components,this kind lens has the deficiency of slow zoom speed, high price, and bad ruggedness, which restrictits performance and miniaturization. With the continuous development of science and technologyand the improvement of people’s material life, there are new requests to variable-focus lens,miniaturization and integration. To realize miniaturization and integration and to fulfill automaticfocusing function based on electrowetting, two liquids/three liquids variable-focus lens are studiedand fabricated in this article. Related research works and achievements are below:1. Research background is described from the miniaturization development trend ofvariable-focus lens and present research status of electroweting technology; research aims,meanings and basic train of thought are clarified; the theory of interface tension, the physical andchemical theory of electroweting technology and the existing problems in electrowetting ondielectric (EWOD) are introduced; at last some applications based on electrowetting are described.2. Two liquids/three liquids variable-focus lens based on EWOD are designed and fabricated,device fabrication process and the relevant fabrication parameters are introduced, and theperformance is tested. CCD imaging measurement system is utilized to measure the focal length ondifferent voltages, and variation of interface shape is analyzed. The relationship between twoliquids/three liquids lens and voltage is derived through Gauss optical theory, MATLAB isemployed to plot this relationship to comparing the experimental focal length values and thetheoretical value.3. Simulation software “COMSOL” is employed to establish two liquids/three liquidselectrowetting-based lens theoretical models, interface shape and the fluid velocity field areanalyzed, the effect of dynamic viscosity coefficient is discussed.