Tilting mirror beam deflector and digital deflection sensor

A new form of piezoelectrically driven mirror optical beam deflector has been developed for optical tracking applications. Single 1- 1/2 inch × 2 inch mirrors actuated by lead zicronate titanate bender elements produce one-dimensional deflection angles of ± 1 degree with a base bandwidth of 300 Hz and an applied signal of 800 volts peak to peak. Eight of these mirrors were used in tandem to provide two-dimensional deflection over ± 4 degree angles, covering a one-inch aperture with over 4 million separately resolvable beam positions. Bandwidth was optimized by mounting each mirror on three transducers so as to achieve tilting without wasted transverse motion. In addition, the mirrors were of honeycomb construction to minimize mass while preserving optical flatness to better than one-tenth wavelength.