title: Balloon telescope optics.
abstract: The article deals with optical problems associated with making infrared astrophysical observations with a balloon-borne telescope. Advantages and difficulties associated with such high altitude observations are reviewed. Topics treated are incandescence of components of the instrument in the infrared, infrared resolving power in the laboratory contrasted with that in the observatory; data documentation; collimator/planet-simulator; novel balloon telescope, and corrections of spherical aberration therein; vignetting and focusing; astigmatism correction; image slicer; grating spectrometer, and correction of aberrations therein; Benedictine slits; and detector-refrigerator and its optics.
authors.affiliation: The Laboratory of Astrophysics and Physical Meteorology, The Johns Hopkins University, Baltimore,Maryland 21218, USA.
authors.forename: J
authors.initials: J
authors.lastname: Strong