X-ray diffraction can be used as the signal for tomographic reconstruction and provides a cross-sectional map of the
crystallographic phases and related quantities. Diffraction tomography has been developed over the last decade using
monochromatic x-radiation and an area detector. This paper reports tomographic reconstruction with polychromatic
radiation and an energy sensitive detector array. The energy dispersive diffraction (EDD) geometry, the instrumentation
and the reconstruction process are described and related to the expected resolution. Results of EDD tomography are
presented for two samples containing hydroxyapatite (hAp). The first is a 3D-printed sample with an elliptical crosssection
and contains synthetic hAp. The second is a human second metacarpal bone from the Roman-era cemetery at
Ancaster, UK and contains bio-hAp which may have been altered by diagenesis. Reconstructions with different
diffraction peaks are compared. Prospects for future EDD tomography are also discussed.
We have developed microstructured Lu2O3:Eu scintillator films that provide spatial resolution on the order of micrometers for hard X-ray imaging. In addition to their outstanding resolution, Lu2O3:Eu films also exhibits both high absorption efficiency for 20 to 100 keV X-rays, and bright 610 nm emission whose intensity rivals that of the brightest known scintillators. At present, high spatial resolution of such a magnitude is achieved using ultra-thin scintillators measuring only about 1 to 5 μm in thickness, which limits absorption efficiency to ~3% for 12 keV X-rays and less than 0.1% for 20 to 100 keV X-rays; this results in excessive measurement time and exposure to the specimen. But the absorption efficiency of Lu2O3:Eu (99.9% @12 keV and 30% @ 70 keV) is much greater, significantly decreasing measurement time and radiation exposure. Our Lu2O3:Eu scintillator material, fabricated by our electron-beam physical vapor deposition (EB-PVD) process, combines superior density of 9.5 g/cm3, a microcolumnar structure for higher spatial resolution, and a bright emission (48000 photons/MeV) whose wavelength is an ideal match for the underlying CCD detector array. We grew thin films of this material on a variety of matching substrates, measuring some 5–10μm in thickness and covering areas up to 1 x 1 cm2, which can be a suitable basis for microtomography, digital radiography as well as CT and hard X-ray Micro-Tomography (XMT). The microstructure and optical transparency of such screens was optimized, and their imaging performance was evaluated in the Argonne National Laboratory’s Advanced Photon Source. Spatial resolution and efficiency were also characterized.