Adaptive secondary mirror demonstrator: design and simulation

Atmospheric turbulence distorts the wavefront of the incom- ing light from an astronomical object and so limits the ability of a tele- scope to form perfect images. Adaptive optics is a combination of tech- nologies that enable the correction of the wavefront distortion in real time. Conventional adaptive optics operate like auxiliary instruments and use additional relay optics, which reduce total throughput and introduce extra IR emissivity and polarization. Adaptive secondary mirrors avoid additional optical surfaces by providing the optical correction at an exist- ing telescope surface (the secondary mirror). Previous studies have demonstrated the optical efficacy and mechanical feasibility of perform- ing the adaptive correction in this way. A technique demonstrator is be- ing developed to explore features and capabilities applicable to a large adaptive secondary mirror and to explore manufacturing, assembly/ disassembly, calibration, and measurement techniques. The paper de- scribes the design of the demonstrator and its predicted performance. © 1999 Society of Photo-Optical Instrumentation Engineers. (S0091-3286(99)00809-0) Subject terms: adaptive optics; deformable mirror; wavefront corrections; sec- ondary mirror.