Image motion analyses of a wide field telescope

Abstract

An image motion analysis is essential for estimating the optical and the opto-mechanical performances of a wide field telescope optical system under a severe windy environment. A wide field telescope is a Richey-Chretien telescope that covers a 2° field of view with two hyperbolic mirrors, a 0.5 m primary mirror and a 0.2 m secondary mirror, and correction lenses. In this design and development study, the telescope structure had to be optimized with the minimal image motion of less than 9 µm during operation environment. To fulfill this design requirement, we performed the image motion analyses from the dynamic response based on the line of sight (LOS) sensitivity equations, which had been derived from the optical design program Code V, integrated in the finite element models by using the NX NASTRAN.