Note: Computer controlled rotation mount for large diameter optics
  We describe the construction of a motorized optical rotation mount with a 40 mm clear aperture. The device is used to remotely control the power of large diameter laser beams for a magneto-optical trap (MOT). A piezo-electric ultrasonic motor on a printed circuit board (PCB) provides rotation with a precision better than 0.03 deg and allows for a very compact design. The rotation unit is controlled from a computer via serial communication, making integration into most software control platforms straightforward. 
Ana Rakonjac, Kris O. Roberts, Amita B. Deb and Niels Kj{\ae}rgaard
physics.ins-det