Adaptive fluidic PDMS-lens with integrated piezoelectric actuator

We present the first adaptive microfluidic PDMS-lens system with an integrated piezoelectric pumping actuator. The system is fabricated in a highly streamlined fabrication process through casting via a hot embossing machine and subsequent oxygen bonding of the layers. With an optimized piezo actuator the achieved focal length ranges from 30 to 500 mm at a voltage from -9 to 44 V. We show that the lens resolution is crucially dependent on the thickness of the lens membrane. For an optimum thickness of 230 um at 5 mm diameter the lenses achieve a resolution of 120 linepairs/mm at a contrast of 50 %.