The mechanical and optical arrangement of the 160-cm aperture, 90-m focal length, McMath Solar Telescope is described. Efforts have been made to obtain good images by thermal control of the optical paths and by selection of fused quartz or metal-based mirrors for the optical components. The optical paths and performances of a vacuum double-pass spectrometer and single-pass spectrograph are illustrated. Resolution of 600,000 and a total scattered light of 3% are obtained in double-pass.
A. Keith Pierce, "The McMath Solar Telescope of Kitt Peak National Observatory," Appl. Opt. 3, 1337-1346 (1964)