title: Simulation, fabrication, and characterization of a tunable electrowetting-based lens with a wedge-shaped PDMS dielectric layer.
abstract: Microlenses with tunable focal length have wide applications in optofluidic devices. This work presents a numerical and experimental investigation on a tunable electrowetting-based concave lens. Optical properties such as focal length of the lens and visibility of images were investigated numerically and experimentally. A finite element analysis and a ZEMAX simulation were used for determination of surface profile and focal length of the lens. The results show that the theoretical surface profile and focal length of the lens are in good agreement with the experimental ones. The lens has a wide tuning focal length equal to 6.5 (cm). Because the polydimethylsiloxane (PDMS) layer is wedge shaped (as both the dielectric and hydrophobic layers), lower applied voltage is needed. A commercial program was used to find the focal length of the lens from maximum visibility value by tuning the applied voltage.
authors.forename: Mohammadreza Salehi
authors.initials: MS
authors.lastname: Moghaddam
authors.forename: H
authors.initials: H
authors.lastname: Latifi
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Shahraki
authors.forename: Mohammad Sadegh
authors.initials: MS
authors.lastname: Cheri