Liquid crystal optical phased arrays are an enabling technology for a variety of photonic and electronic beam manipulation functions, including steering, control of polarization, and amplitude and phase modulation. For applications in the emerging field of space laser communications, such devices would need to survive in the space environment for 10 to 15 years. To assess suitability and identify potential issues, a series of experiments were conducted in which nematic liquid crystal devices were subjected to three radiation environments: total dose (gamma), prompt dose (x rays), and fast neutrons. Tests were conducted using simple phase retarder devices, which served as surrogates for beamsteering devices. Impacts to optical and electrical characteristics of the devices at 1.55 μm were measured after incremental exposure trials. Modest effects were observed, but none were deemed significant enough to impact performance of the devices for space communication beamsteering applications.
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