Dielectrophoretic liquid lens driven by interdigitated sidewall electrodes

Abstract

This paper proposes a dielectrophoretic (DEP) liquid lens that is driven by interdigitated electrodes distributed on the sidewalls and has a structure similar to that of the electrowetting one produced by the company Corning. The interdigital electrodes are formed by winding double flexible wire electrodes wrapped in dielectric layers on the sidewall. Compared with the traditional planar electrode DEP lens, the proposed model ensures the stability of the optical axis of the liquid lens, simplifies the construction process of the interdigital electrode, realizes a continuous change in the focus from negative to positive, and reduces the response time. A truncated conical cavity dielectrophoretic liquid lens with an aperture of 5 mm is fabricated. When the voltage is 0–260 Vrms, it can reach shortest negative and positive focal lengths of −100 mm and 100 mm with a driving time of 190 ms and a relaxation time of 133 ms.