Researchers at the University of California at Berkeley Microfabrication Laboratory (Berkeley, CA, USA; microlab.berkeley.edu) have fabricated a MEMS-based microscanner that can rotate a mirror 24,000 times a second with great precision. According to researchers Hyuck Choo and David Garmire, applications range from a head-up display that projects a video image onto the retina to advanced endoscopy tools outfitted with onboard CT scanners for 3-D medical imaging. Says Choo, "Our method involves only a few processing steps and uses only tools that are conventional for processing integrated circuits."
The microscanners were built in the Sensor and Actuator Center. Their mechanical structures form an array of interlocked combs: one set is fixed to the surface of the wafer while the other can move when driven by a voltage. A mirror actuated by the comb drive can be positioned to scan a digital image or steer a laser. The researchers are building MEMS-based phase-shifting interferometers that measure transient phenomena such as cell growth.
