FABRICATION OF CONTINUOUS-RELIEF MICRO-OPTICAL ELEMENTS BY DIRECT LASER WRITING IN PHOTORESISTS

A laser writing system for the fabrication of continuous-relief micro- optical elements in photoresist is described. The technology enables a wide range of planar micro-optical elements to be fabricated and repl icated into polymer film using Ni shims electroformed from the photore sist originals. The advantages and limitations of laser writing techno logy for micro-optics fabrication are discussed. Examples of fabricate d micro-optical elements include Fresnel microlenses and microlens arr ays, kinoforms, and other continuous-relief phase elements.