Fabrication of microlens arrays with varied focal lengths on curved surfaces using an electrostatic deformed template

A microlens array (MLA) with varied focal length was fabricated on a curved surface for the application of compound-eye imaging. Electrostatic deformed concave membrane was used as the initial molding template, and the deformation was determined by different applied voltage. By transferring the pattern to another polymeric template and deforming it by negative pressure, MLAs on a curved surface were fabricated successfully by using this molding process and polymeric template. The fabricated MLAs were optically characterized and the result demonstrated a larger field-of-view than that of flat MLAs and better imaging performance than that of MLAs with uniform focal length on curved surfaces. (paper)