Electrostatic Micromachined Resonating Micro-Scanner for Circumferential Endoscopic Bio-Imaging

An electrostatic actuation-based resonating microelectromechanical systems (MEMS) polygonal mirror micro-scanner is developed for endoscopic probes used in clinical investigations. Microassembly technology is utilized to construct this device, which consists of a micro-actuator of four sets of electrostatic comb-drive resonators and an eight-slanted-facet highly reflective pyramidal polygon micro-reflector. The pyramidal polygon micro-reflector is developed using high precision diamond turning and soft lithography molding technologies. An optical scan angle of near-360 degrees is achieved at a resonant frequency of 180 Hz when driven by electrostatic comb-drive resonators with 80 Vpp ac voltage.