Measurement system for full three-dimensional motion characterization of MEMS

Advanced testing methods for the dynamics of mechanical microdevices are necessary to develop reliable, marketable microelectromechanical systems (MEMS). A key purpose for mechanically testing MEMS is to provide feedback of measurements that can help the designer progress in an iterative process from prototypes to fully developed products. The effectiveness of these procedures is markedly enhanced if the measurements include high-speed dynamic visualizations of mechanical structures in the microsystem. These data can be obtained using a measurement system that is capable of stroboscopic imaging, interferometry, and digital-image processing. We present such a system and demonstrate its capabilities in three disparate MEMS applications: a gimballed microactuator built for a miniaturized magnetic-disk information-storage system; a micromirror array for an adaptive-optics system; and a microgyroscope that can be applied in a number of microsystems.