Surface scatter effects in grazing incidence x-ray telescopes

Abstract

Non-intuitive surface scatter effects resulting from practical optical fabrication tolerances frequently dominate both diffraction effects and geometrical aberrations in high resolution grazing incidence x-ray telescopes. The resulting reduction optical performance due to scattering is a strong function of x-ray energy, residual surface characteristics, incident angle, and the optical performance criterion appropriate to the application. A simple Fourier treatment of surface scatter phenomena, based upon a non-paraxial scalar diffraction theory, is referenced and utilized to produce parametric performance predictions that provide physical insight and understanding into the surface scatter phenomenon and its effect upon image quality. The optical prescription for the Solar X-ray Imager will be used as an example.