Table of Contents
X-Ray Optics and Instrumentation
Volume 2010, Article ID 421945, 7 pages
Research Article

Focusing X-Rays with Curved Multiplate Crystal Cavity

1Department of Physics, National Tsing Hua University, Hsinchu 300, Taiwan
2Experiment Facility Division, National Synchrotron Radiation Research Center, Hsinchu 300, Taiwan
3RIKEN, XFEL Project Head Office, Experimental Facility Group, Spring-8/RIKEN, Mikazuki, Hyogo 679-5148, Japan

Received 26 January 2010; Accepted 23 July 2010

Academic Editor: Gene Ice

Copyright © 2010 Ying-Yi Chang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


An overview is given of the study on X-ray focusing using the Fabry-Perot type multi-plate silicon crystal cavities consisting of compound refractive lenses. Silicon (12 4 0) is used as the back reflection for cavity resonance at the photon energy of 14.4388 keV. Measurements of focal length of the transmitted beam through the crystal cavities show enhanced focusing effect due to the presence of back diffraction. Also, an incident beam with ultrahigh energy resolution can improve the focusing owing to the wider acceptance angle of the back diffraction. Considerations based on the excitation of dispersion surface within the framework of X-ray dynamical diffraction theory are also presented to reveal the origin of this enhanced focusing.