Dark-field X-rays Dissipate Structural Fog
Now they have been obtained using conventional X-ray tubes, an advance that could pave the way to revealing micro-cracks in aircraft or boat hulls, bone splinters and on the analytical side , identifying explosives Pfeiffer et al., Nature Materials.
A team from Switzerland and Denmark has incorporated a nanostructured grating interferometer into an X-ray setup that allows brightness and bandwidth restrictions to be overcome.
Nanostructured gratings permit the use of a broad energy spectrum, including the standard range of energies that are used in traditional X-ray equipment. Current imaging equipment can be adapted to include dark-field imaging data obtained from small-angle scattering, revealing information on the microporous or microcrystalline structure of the material. Another possibility is Lang topographs to fingerprint gemstones.
Potential applications include security screening as explosives with microcrystalline structures can be identified by their ability to scatter X-rays.The literally stark contrast between these chicken wing images demonstrates the potential of dark-field imaging in medical applications.
“In cases of complicated bone fractures, where small splinters can intrude into the surrounding tissue, dark-field contrast could provide the necessary specificity to visualize subtle details"
lead author Franz Pfeiffer of the Paul Scherrer Institut, Switzerland, told Nature