TABLE OF CONTENTS The goal of this chapter is to describe the state of the art in membrane mirrors with a strong emphasis on the development of primary mirrors for space telescopes. The term membrane mirror is used here in reference to a reflector with large diameter-to-thickness ratio larger than 10 4 and envisioned possibly to be as high as 10 7. The term membrane indicates the mechanical response is dominated by extension rather than bending, and the term mirror indicates an absolute position tolerance on the reflecting surface that is generally only a fraction of the wavelength of the light being observed. The optical portion of the spectrum is the most typical wavelength band of interest for telescopes. What follows is a discussion of the technology areas important to membrane mirrors, from both the top-down perspective of what is required to make the system work and the bottom-up perspective of what research progress has been made toward realizing the technology.
This chapter should be seen as a complementary extension and update to the membrane optics chapter in a previous volume on gossamer spacecraft.1 The previous work contains a significant amount of relevant content; the current effort has a different organization and different emphasis on technology. Notable discussions in the previous chapter cover the following topics.
Challenges of using initially-planar surfaces as doubly curved mirrors both the analytical background and experimental evidence.
Optical layouts for metrology of the surface quality.
Wavefront compensation by real-time...
