MICROMACHINED FREE-SPACE INTEGRATED MICROOPTICS

The surface-micromachining technique has been employed to fabricate no vel three-dimensional micro-optical elements for free-space integrated optics. The optical axes of these optical elements are parallel to th e substrate, which enables the entire free-space optical system to be integrated on a single substrate. Microscale Fresnel lenses, mirrors, beam-splitters, gratings, and precision optical mounts have been succe ssfully fabricated and characterized. In addition, micropositioners su ch as rotary stages and linear translational stages are monolithically integrated with the optical components using the same surface-microma chining process to provide on-chip optical alignment or optomechanical switching. Self-aligned hybrid integration with semiconductor edge-em itting lasers and vertical cavity surface-emitting lasers are also dem onstrated for the first time. This new free-space micro-optical bench (FSMOB) technology could significantly reduce the size, weight, and co st of most optical systems, and could have a significant impact on opt ical switching, optical sensing and optical data-storage systems as we ll as on the packaging of optoelectronic components.