Very fast optical beam steering and wave front correction can be achieved by employing phased arrays of lightweight High Contrast Grating (HCG) MEMS mirror etalons. The etalons provide a large phase shift for a small displacement, 100x more than traditional reflective mirror elements. Operating such etalon arrays requires exquisite control of the MEMS mirror displacements. Our aim is to use in-situ stroboscopic interferometric imaging of the etalons to ensure phase accuracy and combat long term-drift, while employing feed-forward electrical input shaping to achieve fast settling time and precise phase tracking in a power-efficient way.
Project end date: 12/20/13