Revolutionary Beam Steering Technology for Imaging Laser Radar

Currently the development of ladar seekers is often limited by beam directing mechanisms, which are usually operated by costly, bulky and power hungry voice-coil or electro-mechanical actuators. Umachines proposes to demonstrate the innovative architectureof compact scanning mirrors with sub-millisecond response time based on MEMS technology. This architecture is the next logical evolution of our individual mirror technology and makes use of micromirror arrays to achieve large scanning angles and high-speedresponse independent of optical aperture sizes. Additionally, we are going to develop a new packaging scheme which could address large arrays of mirror pixels. In the Phase I effort, we propose the following techniques to replace the current mechanicalraster scan in the laser ladar systems:(1) Examine micromirror arrays architecture with sub-millisecond response time independent of aperture size(2) Develop practical I/O methods compatible with high resolution micromirror arrays by fabricating bottom electrodes with BSB (backside solder bump) to perform low temperature solder bonding with IC control circuits(3) Proof of concept of how the proposed micromirror arrays could be integrated into imaging ladar systems The MEMS fabrication process for making micromirror arrays with flat surfaces and hidden mirrors provides a solid basis for many optical MEMS devices. There is no doubt that feasible and low cost MEMS processes could also benefit other research works orcommercial products. MEMS micromirrors with flat surfaces and high fill factors are a must-have factor for practical applications such as displays or optical telecom communications systems.BSB provides a practical packaging solution for high resolution devices such as micromirror arrays. We expect that in the near future, more and more MEMS devices are going to be fabricated on a single chip with control electronics. As I/O number increases,the BSB could form the packaging cornerstone for other devices (not necessarily optical MEMS) that need large numbers of I/O.