Open AccessA desktop X‐ray monochromator for synchrotron radiation based on refraction in mosaic prism lenses
Author(s) -
Liu Tao,
Simon Rolf,
Batchelor David,
Nazmov Vladimir,
Hagelstein Michael
Publication year - 2012
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049511052307
Subject(s) - optics , pinhole (optics) , lens (geology) , focal length , prism , x ray optics , monochromator , achromatic lens , aperture (computer memory) , beamline , refractive index , physics , photon energy , synchrotron radiation , materials science , photon , beam (structure) , x ray , wavelength , acoustics
Focusing planar refractive mosaic lenses based on triangular prism microstructures have been used as an alternative approach for wide‐bandpass monochromatization of high‐energy X‐rays. The strong energy dependence of the refractive index of the lens material leads to an analogous energy dependence of the focal length of the lens. The refractive mosaic lens, in comparison with the refractive lens of continuous parabolic profile, is characterized by a higher aperture because of reduced passive material. In combination with a well defined pinhole aperture in the focal plane, the transmittance of photons of an appropriate energy can be relatively high and photons of deviating energy can be efficiently suppressed. The photon energy can be tuned by translating the pinhole along the optical axis, and the bandwidth changed by selecting appropriate pinhole aperture and beam stop. This method of monochromatization was realised at the ANKA FLUO beamline using a mosaic lens together with a 20 µm pinhole and beam stop. An energy resolution of 2.0% at 16 keV has been achieved.