3D Light Field Projection and the Associate 3D Photolithography

Abstract

Abstract 3D light field camera has been provided as a valid method to capture 3D surface topography with a microlens array. Through inverting the propagation direction, 3D virtual image projection can also be achieved with conventional optics and a microlens array. By compressing the 3D virtual image from the microlens array with an additional lens, microscale 3D virtual image can be achieved. We propose that microscale 3D virtual image can be valuable in microscale 3D fabrication. In this study, we provide a theoretical basis to combine femtosecond laser with the above mentioned 3D virtual image reconstruction scheme to cure photopolymers. With multiphoton effects induced by femtosecond laser, we expect 3D patterning of regions inside the photopolymer can be possible. Compared with the demonstration of 3D patterning with continuous near UV light and the proposed 3D light field projection scheme, curing of photopolymer can be limited to focal points (i.e., voxel) of the projected microscale 3D surface with two photon absorption effect when femtosecond light with high enough intensity is applied. The required femtosecond light intensity is also determined in this study. We expect this new 3D photolithography method can be valuable in fast and high precision patterning of micro to macro structures in materials that are photoactive.