Optical Characterization of Repositionable Liquid Micro-Lenses

A reconfigurable micro-lens array based on a transparent substrate and liquid micro-lenses actuated by electro-wetting on dielectrics (EWOD) is presented. The substrate features an array of electrodes and a surface structure with a periodicity smaller than that of the electrode array. The device is shown to be capable of individually adjusting the position and the focal length of liquid micro-lenses. Measurements of the focal length as a function of applied voltage are presented. The tunable micro-lens array may have applications for adaptive wavefront sensing, for parallelized confocal microscopy, and for parallel optical tweezers.