Flip-chip integration of lenslet arrays on segmented deformable micromirrors

Flip chip assembly technology offers a reliable and advanced packaging approach for hybrid integration of micromachined optical components. In this paper we present flip chip integration of microlens arrays with surface micromachined segmented deformable micromirrors. 12 by 12 electrostatic micromirror arrays were fabricated through a commercial surface micromachining process and integrated with glass microlenses. A commercial glass microlens array is positioned directly over the micromirror. The use of a lenslet to focus the incoming laser beam onto the reflective surface of a micromirror substantially increases optical efficiency of the hybrid microsystem. For mirror deflections much smaller than the lenslet focal length, the lenslet/micromirror combination behaves as a phase-only modulating optical element. The hybrid lenslet/MEMS arrays thus serve as rugged, compact optical elements for beam steering, beam shaping, and aberration correction applications.