Planar Variable-Focus Liquid Lens Based on Electrowetting on Dielectric

In this paper, a new type of liquid lens based on electrowetting on dielectric (EWOD) is demonstrated. It consists of a transparent liquid droplet as lens on a hydrophobic dielectric film, a patterned indium tin oxide (ITO) film as a set of transparent electrodes underneath and a glass substrate. By changing the applied voltage on the set of electrodes, the shape and location of the droplet can be adjusted reversibly which tune the focal length and position of the lens. It has some good qualities such as wide variability of focal length up to 20%, fast response time, low applied voltage and low power consumption. It can be used widely in optical application.