Optical Design And Performance Analysis Of The Variable-focus Optical System Using Electrowetting-based Double Liquid Lens

The variable-focus optical system is widely used in many optical devices because it can quickly change the focal length in a certain space range. Traditional variable-focus optical system is usually composed of two or more fixed lenses, which change the focal length by using the mechanical or optical compensation theory. Such mechanical equipment makes traditional variable-focus optical system low response velocity, very expensive, and fragile. Therefore, the development of the variable-focus optical system with long life, high stability and small volume is the demand of the future, and it also has a very important value of application and a great market prospects.The work of this paper is to design a variable-focus optical system and analyze its performance which based on the self-developed electrowetting-based liquid lens. First of all, a variable-focus optical system without mechanical movement are designed by using the electrowetting-based double-liquid lens; Secondly, a triple-liquid lens is employed to realize the design of the variable-focus optical system; Finally, design a variable-focus optical system with a set of mechanical movement lens of the electrowetting on dielectrics. Based on Gaussian optics theory,the conditions to ensure the stable of the imaging for the variable-focus optical system are deduced.According to the ray tracing method, the focal length of the optical system has been calculated. By using Gauss brackets, the initial structural is analyzed and then a reasonable initial structure are chosen. The structural and imaging performance of the three optical systems have been compared and analyzed by using ZEMAX. The research of this paper provides the basic guidance and reference for the liquid lens design of the variable-focus optical system.