Variable focus microlens array with curved electrodes

Abstract

In this paper, a liquid crystal microlens array with a curved electrode is designed and fabricated. The fabrication process consists of two parts: fabricating the microlens array and assembling the liquid crystal cell. The first process utilizes the hydrophilic confinement effect, an inkjet printer, and the replication process to fabricate a microlens array on a glass substrate. A transparent, organic, conductive poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT:PSS) is spin-coated on the microlens array as a curved electrode, and the microlens array is further flattened by SU-8 photoresist. It is then assembled with indium tin oxide glass. Interference patterns for the liquid crystal microlens array are measured and agree well with theoretical calculations. From interference patterns, the focusing power range is measured to be from −47.28 to −331 diopters under 10 V, which corresponds to focal length from −2.12 cm to −0.3 cm at 532 nm wavelength. This technology could be useful for optical zoom systems or focus-tunable lens applications.