Hybrid Diffractive-Refractive Liquid Lens For Variable-focus Optical System

The hybrid diffractive-refractive variable-focus liquid lenses composed of a liquid refractor and a binary optical lens are demonstrated in this letter. Most of the conventional variable-focus liquid lenses play an important role in modern photonic devices and they are used in a wide range of applications such as all kinds of photonic packages. However, the conventional variable-focus liquid lenses have the characteristic of chromatic aberration. With the rapid development of binary optics, we know the color separation properties of binary optic lenses are opposite in sign to those of traditional lenses. Here we demonstrate two types of hybrid diffractive-refractive variable-focus liquid lenses which contain two components, the liquid refractor and the binary optical lens. Unlike other conventional liquid lens, one surface of these lenses is binary optical surface. The lenses being constructed using combined diffractive /refractive elements are propitious to solve the problem of chromatic aberration.In this paper, the function of the surface of the hybrid diffractive-refractive variable-focus liquid lens and the relationship between the changing of focal length and the adjustment of the radius of curvature of the refractive lens are proposed. The simulations show the structure of the hybrid diffractive-refractive variable-focus liquid lens and indicate that the quality performances are better than conventional refractor. From the evaluation of the results, the hybrid diffractive-refractive variable-focus liquid lens presents the simplest and the highest-quality performances. The color aberration is solved well when the focal length of the optical system is changed. In conclusion, the lens we demonstrated is desirable for both civilian and military applications.