Liquid lens with double tunable surfaces for large power tunability and improved optical performance

In this paper we propose a liquid lens with two tunable interfaces formed by two kinds of immiscible liquids. The proposed liquid lens uses liquid pressure to change the shape of the interfaces. It can provide a large tunable range of optical power and improved optical performance. By applying suitable liquids the gravity effect can also be negligible. To prove the principles, a liquid lens with 7 mm aperture was fabricated. The optical performance indicates that the proposed liquid lens can provide a large tunable range of both positive and negative powers even using liquids with small differences in refractive indices. The resolution is better than 50 lp mm(-1) under white light environment. The spherical aberration and coma are also largely reduced. The proposed liquid lens can also provide the optical designer with the freedom to choose the combination of liquids to reduce or even correct aberrations.