CLESSIDRA: Focusing Hard X-Rays Efficiently with Small Prism Arrays

Abstract

CLESSIDRA is Italian for hourglass, which is a good description of the appearance of the optical components discussed in this chapter. In these optics, many small prisms are arranged to form two large prisms, which almost touch each other at their tips, giving rise to the focusing of X-rays in one direction. From the optical point of view, CLESSIDRA is a type of Fresnel transmission lens, containing less absorbing material than normal transmission lenses. Its aperture can thus be larger. In this contribution experimental data on the focusing properties will be compared to the predicted characteristics.