Self-assembled high NA microlens arrays using global dielectricphoretic energy wells

Microlens arrays were self-assembled from microballs using dielectrophoretic energy wells. Energy wells defined by patterned dielectric were used to produce microlens arrays with array patterns of desire. Microballs of 25microm in diameter were measured to have numerical aperture of 0.8 and focal length of 15.5microm. The optical resolution was found to be 0.4microm. Both the numerical aperture and the focal length were further adjusted to 0.66 and 19.0microm by a post-assembly heat treatment at 190 degrees C for 5 minutes.