Simple method for fabricating solid microlenses with different focal lengths

Abstract

A versatile method of fabricating different microlenses using a relatively simple process is presented. A liquid-filled lens structure integrated with microfluidic network and liquid Polydimethylsiloxane (PDMS) are used as the frame and filling material, respectively, for the injection process. Through simply changing the injection pressure to obtain different membrane deformation profiles followed by curing, the PDMS stuffing together with the frame will finally form a solid microlens with the corresponding desired focal length. In tests, the fabricated microlenses show good performance in the surface profile and the uniformity between pixels in the array. Focal lengths of microlenses covering a wide range from tens of millimeters to nearly 1.6 mm have also been successfully demonstrated. © 2008 IEEE.