Submicrometre resolution phase-contrast radiography with the beam from an X-ray waveguide

Abstract

Experimental data with unprecedented submicrometre resolution obtained in a phase-contrast radiography experiment in a magnifying con®guration are presented. The term`phase contrast' here indicates that the phase retardation of coherent light in matter was utilized as the contrast mechanism. The coherent and divergent beam exiting an X-ray waveguide was used in a lensless con®guration to magnify spatial variations in optical path length up to several hundred times. The defocused image of a nylon ®bre was measured with a resolution of 0.14 mm at the object. Suf®cient contrast was found for exposure times of 0.1 s, i.e. in the regime for real-time studies.

Imaging collagen packing dynamics during mineralization of engineered bone tissue

“…This multiscale approach is needed due to the fact that collagen fibrils organize into bundles at micrometer scale via interfibrillar cross-links. At this scale, high resolution XPClT is an appropriate tool to visualize collagen bundles since unlike conventional radiography and tomography it is able to image small density variations in weakly absorbing materials such as biological samples [26,27]. On the other hand, SlXRD technique allows to probe both the k-space and real space, visualizing structural features at atomic scale and nanoscale such as the lateral packing of collagen molecules and the size of mineral particles.…”

High aspect ratio x-ray waveguide channels fabricated by e-beam lithography and wafer bonding

“…In particular, in the monomodal regime they also enable the control of the wavefront phase highly desirable for coherent x-ray imaging and holography. 24,[27][28][29] To block the multi-keV photon energy beam in the cladding material, rather long channels are needed with aspect ratios in the range of 10 4 -10 6 , depending on the photon energy E and cross section d.…”

X-ray phase contrast tomography for the investigation of amyotrophic lateral sclerosis

“…In-line free space propagation imaging is based on Fresnel's diffraction patterns after free space propagation (Di Fonzo et al, 1998;Fratini et al, 2015). Despite the advantage offered by the easier experimental set-up compared with complex optical systems, propagation images contain both absorption and phase contribution.…”