Segmented bimorph deformable mirror

Abstract

The efficient low-voltage bending properties of PZT bimorph wafers have been combined with conventional microelectronics techniques to produce a 37-hex-faceted deformable mirror 23 mm in diameter and 1 mm thick. Despite the high ratio of diameter to thickness, at 633 nm an overall flatness of better than one-half wave peak-to-valley (PV) and one-tenth wave RMS is attained under an active figure control of about 7 V per wave. Evaporative deposition of the electrical contact pattern eliminates mechanical coupling to the bimorph and allows the device to perform to frequencies in excess of 10 kHz.