Fabrication of controllable profile microlens array by nanoimprinting process

A thermal imprinting process with a cylindrical mold is proposed to fabricate the microlens array using glass as raw material. In this study, the function of the mold is to decide the position of the microlens array instead of define the profile of the microlens, which is different from that of the conventional imprinting process. Microlens arrays are shaped because of the cohesion and surface tension of the glass material. Because of the surface of microlens didn't contact the mold, no adhesion phenomena occurred when implementing the procedure, which can eliminate the adhesive issue. By regulating the imprinting force, various focal lengths of microlens are produced. Both the molecular dynamics simulation data and experimental results show the same trend and also proof the feasibility of this method.