Aberration effects in curved multilayers for hard X rays are studied using a simple analytical approach. The method is based on geometrical ray tracing including refraction effects up to the first order of the refractive index decrement δ. The interpretation of the underlying equations provides fundamental insight into the focusing properties of these devices. Using realistic values for the multilayer parameters the impact on spot broadening and chromaticity is evaluated. The work is complemented by a comparison with experimental focusing results obtained with a W/B4C multilayer mirror.
International Society for Optics and Photonics
3 Sep 2008
Volume: 7077 Pages: 70770T
Advances in X-Ray/EUV Optics and Components III