A bifocal compound liquid lens with continuous zoom based on selective wettability

In this paper, a tunable zoom bifocal liquid lens based on selective wettability is proposed. This lens consists of internal and external immiscible coaxial droplets surrounded by immiscible ambient liquid. Since curvatures and refractive indexes of the internal and external droplets are different, the system forms a long focus and a short focus, respectively. By applying different voltages, the curvatures of the internal and external droplets change exerting continuous movement of a long/short focal point in a certain range. To verify the feasibility and practicability of this concept, a prototype of the bifocal compound lens is fabricated in experiment, and the modulation ability of its long/short focal length is detected. The short focal length of our proposed lens varies from 15.46 mm to 17.47 mm, while the relative long focal length ranges from 96.25 mm to 70.31 mm driven by 200 V. (C) 2022 Optica Publishing Group

Automated summary

This paper proposes a tunable zoom bifocal liquid lens based on selective wettability. The lens consists of immiscible internal and external droplets that can change their curvatures by applying different voltages, resulting in continuous movement of the long and short focal points. Experimental results demonstrate the feasibility and practicability of this concept.