Feasibility of a 3.5 m diameter, segmented, solid, exit window for a high-power laser beam director was investigated. Effects of laser heating, gravity, and differential pressure loads were analyzed. A design was found for which structural deflections and stresses were within allowable limits. The time-varying optical aberrations introduced by the window were less than 0.01 1.tm rms after removal of bias, tilt, and focus aberrations for two window materials. Static aberrations caused by differences in optical thickness of the finished window panels were found to be relatively large and potentially uncorrectable if common optical finishing tolerances were assumed. Three potential solutions for accommodating the optical thickness variations are discussed.
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