Imaging Optics for electromagnetic radiation above 0.05 keV (X-rays and gamma-rays) offer brand-new astrophysical insights. The radiation of interest ranges from the highly red-shifted X-rays emitted by primeval black holes to characteristic supernova Ia Gamma-ray emission lines providing insight in the processes of explosive nucleosynthesis or the deceleration of the cosmic expansion.

Two instrument types offer the possibility to efficiently focus high-energy radiation:

Grazing angle mirrors make use of small angle reflection of X-ray and low-energy gamma-rays. In order to overcome heavy and bulky solid metal reflectors, ongoing technology research is investigating lighter but nonetheless stiff mirror structures, leading to the design of pore optics. Silicon pore optics ("high precision optics, HPO") are currently developed for astrophysics missions on satellites in earth orbit, the lighter but less precise glass pore optics ("micro-pore optics, MPO") are under investigation for missions into the solar system. Additionally, single- and multi-layer coatings are developed to enhance the reflectivity.

Crystal diffraction lenses make use of Laue diffraction in order to focus high-energy gamma-rays.