Geometries for Grazing Incidence Mirrors

Grazing incidence optics simultaneously provide X-ray images and high signal-to-noise sensitivity by focusing emission to a small detector region. The Wolter I geometry and derivatives from this optical prescription have been the design used by most X-ray telescopes flown on satellite missions. In this chapter, we will review the motivations for the broad adoption of the Wolter I design and study in detail the equations that govern the optical prescription of it, as well as the cone approximation of the Wolter I and a simple parabolic mirror. We conclude with a brief discussion of other telescope designs under consideration.