Abstract

The University of Arizona is building the Large Binocular Telescope (LBT) which requires twin 8.4-meter diameter, f/1.14 paraboloidal primary mirrors that have 1.38 mm departure from the best fitting sphere, more than any other existing or proposed astronomical mirrors. The design, manufacture, and qualification of the optical system that allows interferometric testing of these mirrors poses considerable difficulty. This paper shows four different types of designs and discusses the relative merits of each.

© 1998 Optical Society of America