An adaptive liquid lens with radial interdigitated electrode

A newly patterned electrode is designed for a dielectric liquid lens. The electrode has a radial interdigitated structure which can provide a symmetrical-nonuniform fringing field. This electric field can effectively deform the shape of a dielectric liquid droplet in radial direction, causing the focal length of the liquid droplet to change. For a lens using glycerol as the droplet and optical oil (SL-5267) as the surrounding medium, its focal length (f) can be tuned in the range of ∼−8.28⩽ f⩽∼−4.4 mm, when the applied voltage is changed from 0 to 120 Vrms. In contrast to previous approaches, the liquid lens with radial interdigitated electrode has the advantages of scalable aperture size, wide variability of focal length, and good optical characteristics. Moreover, the driving voltage is insensitive to the size of the droplet.