Robustness and Reliability of Micromachined Scanning Mirrors

In order to confirm the robustness and reliability of micromachined scanning mirrors, we have measured the mirror-scan repeatability, time-to-failure, temperature sensitivity, and shock durability of micromirrors designed for portable video display applications. The mirror lifetime was more than 45 billion cycles, in this case limited by the cleanliness of the operating environment. The mirror-positioning repeatability is better than 10 microradians, comparable to that of commercially available galvanometric scanners. The resonant frequency decreased by 2.2% for an 80 degree centigrade change in temperature, with a maximum temperature sensitivity of 500 ppm/degree centigrade. The mirrors were capable of withstanding the ANSI/ISA standard drop test for portable electronics with no noticeable change in performance.