Development of microperiodic mirrors for hard x-ray phase-contrast imaging.
Differential phase-contrast imaging with hard x rays can have important applications in medicine, material sciences, and energy research. Phase-contrast methods based on microperiodic optics, such as shearing interferometry, are particularly attractive because they allow the use of conventional x-ray tubes. To enable shearing interferometry with x rays up to 100?keV, we propose using grazing-incidence microperiodic mirrors. In addition, a simple lithographic method is proposed for the production of the microperiodic x-ray mirrors, based on the difference in grazing-incidence reflectivity between a low-Z substrate and a high-Z film. Using this method, we produced prototype mirrors with 5-100?mum periods and 90?mm active length. Experimental tests with x rays up to 60?keV indicate good microperiodic mirror reflectivity and high-contrast fringe patterns, encouraging further development of the proposed imaging concept.
Stutman
Dan
D
Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21030, USA. stutman@pha.jhu.edu
Finkenthal
Michael
M
Moldovan
Nicolae
N