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Long-Wavelength Beam Steerer Based on a Micro-Electromechanical Mirror



Eyal Gerecht, Anthony B. Kos


Commercially available mirrors for scanning THz beams are too large to allow high-speed THz imaging. There is a need for smaller, more agile pointing apparatus to provide THz images in seconds, not minutes or hours. We have developed a fast THz beam steerer using a commercially available micro- electro-mechanical system (MEMS) mirror controlled by a high-performance digital signal processor (DSP). The DSP allows high-speed raster scanning of the THz radiation, which is focused down to a small waist onto the 9mm2, gold-coated, MEMS mirror surface, while simultaneously acquiring an undistorted and high spatial-resolution image of a sample with a large number of pixels. The beam steerer hardware and software are described, and we discuss the performance of the assembled system. An additional feature of the system is that it can serve as a miniaturized, high-performance THz beam chopper, to be used for lock-in detection.
Journal of Research (NIST JRES) - 118.006
Report Number


DSP, image raster-scanning, MEMS, quasi-optical coupling, terahertz, terahertz beams, terahertz imaging, terahertz switching elements


Gerecht, E. and Kos, A. (2013), Long-Wavelength Beam Steerer Based on a Micro-Electromechanical Mirror, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed May 22, 2024)


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Created February 28, 2013, Updated October 12, 2021