提出了一种基于介质上电润湿(EWOD)的液体变焦透镜的新结构.它由一个依次覆盖有ITO透明导电薄膜及疏水介质膜的下极板、悬在其上的一个内外壁均覆盖有疏水层的玻璃锥管以及处于两者之间的导电液滴组成.通过改变ITO与液滴之间的电压大小,透镜的曲率及位置能同时被调节,从而实现对透镜焦距的调节.实验结果表明,该器件在0~50V电压下可实现对2cm至无穷远处物体的聚焦.
A novel self-centered variable focus liquid lens based on electrowetting-on-dielectric (EWOD) is presented, which consists of a glass plate coated with two transparent layers of conductive ITO film and hydrophobic dielectric film, a conical tube partly covered with hydrophobic film positioned with a gap above the glass plate and a water droplet. By changing the voltage applied to the droplet and the ITO control electrode, both the position and curvature of the meniscus between the two immiscible fluids can be reversibly adjusted, thus realizing a lens of variable focal length. The experimental results show that the prototype of the liquid lens with 50 V power supply is able to focus on objects from 2 centimeters up to infinity away with good imaging quality.