Collimator based on a Schmidt camera mirror design and its application to the study of the wide-angle UV and VUV telescope

Abstract

The paper describes a wide-angle collimator based on a “Schmidt camera” mirror design, which is intended for resolution measurements of a telescope operating in the 120- to 380-nm wavelength range. The collimator consists of a test pattern, a spherical mirror, and a mirror wavefront corrector (planoid) compensating for spherical aberration and astigmatism. The test pattern is shifted from the optical axis of the collimator using a flat mirror. The main parameters of the device are as follows: working area diameter of the test pattern, 30 mm; aperture ratio, F/3.2; exit pupil diameter, 250 mm; angular resolution measured in “white light,” 1.4 arc sec; and field of view, 2ω=3 deg. The results of the angular resolution measurements of a two-channel Schmidt–Cassegrain mirror telescope, obtained with the use of the collimator, are given.