Tunable multi-functional optofluidic biconcave lens

Recently using the integrated micro-lens to improve the fluorescence detection in microfluidic systems has been intensively studied. This paper describes the design and demonstration of an optofluidic in-plane bi-concave lens to perform both light focusing and diverging. In both focusing and diverging mode, the optical properties of the lens can be tuned by adjusting the flow rate. Numerical simulation and experiment are conducted and the results are compared. Our device shows a good tunability.