Prototype Telescope Subassembly For The High Resolution Doppler Imager For The Upper Atmospheric Research Satellite

The Prototype Telescope Subassembly (PTS) is a two-axis gimballed telescope that has been designed and built for the University of Michigan. The function of the PTS is to collect light from the earth's upper atmosphere for the High Resolution Doppler Imager (HRDI), a white light interferometer built by the University of Michigan. The PTS/HRDI instrument's mission on the Upper Atmosphere Research Satellite (UARS) is to measure upper atmosphere wind velocities. This paper describes the reflective optics design, first-order fabrication, and test of the PTS. The telescope optics consist of an off-axis Gregorian afocal telecentric design. The gimbal relay optics incorporate additional fiber optics and mirrors for image transfer to the interferometer. The telescope optics and gimbal were manufactured primarily from 5000 series aluminum with the exception of two fiber optics components and one relay lens. The reflective optics are nickel-coated diamond-turned low-scatter postpolished components. The telescope incorporates an extensive low-scatter Lyot stop baffle design.