Large area fabrication of engineered microlens array with low sag height for light-field imaging

Recently, intensive research on microlens array (MLA) was undertaken, which involved intertwining with the light-field imaging in order to obtain four-dimensional information. Although several fabrication approaches for MLA attempted to achieve high density and precision geometry, further progress is necessary. In this study, we present a cost-effective fabrication strategy for geometrically tunable polymer MLA with extremely low sag height (~3 μm) through improved MEMS wet etching process. Additionally, we assemble a hand-crafted light-field camera by integrating the elaborately customized MLA with a commercial digital camera. Finally, we demonstrate representative light-field imaging features including refocusing and all-in focusing image from a single exposure.