Working under a Collaborative Research and Development Agreement, a team of scientists and engineers from the Air Force and Michigan State University have built the first generation of smart material-based micro-electrical mechanical mirror devices (MEMS). They use MEMS mirrors for electro-optical applications and a vanadium dioxide components as a microactuator. Vanadium dioxide —also known as VO2—is considered a “smart” material, meaning it responds rapidly to stimulus, and it is also considered to be multifunctional because many of its properties change simultaneously to the stimulus. It requires little energy to power—at least, much less than other technologies.
MEMS mirrors are used in multiple fields including optical phased-arrays, spectroscopy, optical switches, track positioning, microscopy, optical displays, and medical imaging.
Michigan State University scientists have vast experience in depositing and characterizing VO2, as well as using material in micrometer-sized devices. Air Force personnel participated in testing the device testing, analyzing data analysis, and designing new processes.
The team developed a device that showed a great deal of movement from minimal power during phase transition. During testing it showed vertical movements and tilt angles of 75 micrometers and 5.5 deg. Through the course of the research the material displayed hysteretic behavior, meaning the response to force or stimuli depended on the previous response. The researchers can also predict how the device will react to certain electrical signals and can “program” the devices for specific responses.
“Our collaboration with Michigan State University has been invaluable in advancing the science and technology of micro actuators and micro mirrors,” said the Air Force’s John Ebel. “Their expertise combined with Air Force Research Lab’s unique fabrication capabilities and talents has greatly accelerated the pace of research for MEMS actuators and mirrors.”