光学 精密工程, 2014, 22 (10): 2592, 网络出版: 2014-11-06
电润湿双液体变焦透镜
Electrowetting-based variable-focus double-liquid lens
双液体透镜 变焦距透镜 电润湿驱动 COMSOL软件 double-liquid lens variable-focus lens electrowetting drive COMSOL software
摘要
研制了介电润湿双液体变焦透镜以实现变焦透镜的微型化及无机械部件情况下透镜的自动变焦。基于介电润湿原理制备了双液体变焦透镜。采用CCD图像测量系统,测量了不同电压下透镜的焦距,并与基于高斯光学理论推导的焦距公式进行了比较。然后,采用COMSOL软件,分析了双液体界面面形随电压的变化,讨论了动力黏度系数对透镜性能的影响。结果表明,随着电压的增大,双液体界面从初始弯向导电盐溶液变为平面继而弯向绝缘油,相应的双液体透镜实现了从凹透镜到凸透镜的转变,临界电压为50 V。当电压增大至65 V左右时,透镜焦距不再减小。透镜焦距经历了从负到零再到正的变化(-∞ ,-22.83 mm)∪(33.47 mm,+∞),基本实现了焦距大范围可调。当动力黏度系数为0.03时,液体透镜的响应时间为0.015 s,对应的器件稳定性最佳。
Abstract
An electrowetting-based double-liquid lens was developed to realize the small volume and automatic focusing without mechanical components for the focus-variation lens. The electrowetting-based double-liquid lens was designed and fabricated based on the dielectric wetting principle. Then, the focal length of liquid lens for different voltages was measured by a CCD image measurement system and it was compared with the theoretical value calculated by Gauss optical theory. Finally, COMSOL was employed to analyze the curvature radius of the double liquid interface at different voltages and to discuss the effect of dynamic viscosity on the response time and stability of the liquid lens. The results indicate that the double liquid interface bends to the conductive salt solution initially and then changes into a plane and finally bends to the insulating oil when the applied voltage is increased. Accordingly, the liquid lens changes from a concave lens to a convex lens, and the critical voltage is 50 V. However, the focal length of the liquid lens does not decrease any more when the applied voltage increases to 65 V. The whole focal length of the lens ranges from -∞ to -22.83 mm and from 33.47 mm to +∞, and it is adjusted continuously in a wider range. Moreover, when the dynamics viscosity of insulating oil is 0.03, the response time is 0.015 s and the corresponding performance of the device is optimal.
赵瑞, 华晓刚, 田志强, 刘启超, 王评, 梁忠诚. 电润湿双液体变焦透镜[J]. 光学 精密工程, 2014, 22(10): 2592. ZHAO Rui, HUA Xiao-gang, TIAN Zhi-qiang, LIU Qi-chao, WANG Ping, LIANG Zhong-cheng. Electrowetting-based variable-focus double-liquid lens[J]. Optics and Precision Engineering, 2014, 22(10): 2592.