A Comparison Of The Merits Of Open-Back, Symmetric Sandwich, And Contoured Back Mirrors As Light-Weighted Optics.

There is a need for reliable mirrors which are both light-weight and stiff. However very little documentation exists that compare different types of light weight mirrors. This lead to this parametric study to compare different mirror types, namely, contoured back mirrors, symmetric sandwich mirrors, and open back mirrors. This paper examines each mirror type as compared in each of several categories: 1) Self weight induced deflection, which is a product of stiffness and weight, for mirrors mounted on their backs and of equivalent thickness. 2) Efficiency of mirrors which are of equivalent weight, where efficiency is a function of self weight induced deflection and mirror thickness. 3) Fabrication constraints including ease of manufacture, ease of mounting, mirror thickness, and quilting or print-through of the mirror face plate. The results obtained in these categories can be used to design light-weight mirrors with greater confidence in preferred mirror type.