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Title: High-resolution differential phase contrast imaging using a magnifying projection geometry with a microfocus x-ray source

Abstract

Differential x-ray phase contrast imaging using a grating interferometer was combined with a magnifying cone beam geometry using a conventional microfocus x-ray tube. This brings the advantages of a magnifying cone beam setup, namely, a high spatial resolution in the micron range and the possibility of using an efficient, low resolution detector, into differential phase contrast imaging. The authors present methodical investigations which show how the primary measurement signal depends on the magnification factor. As an illustration of the potential of this quantitative imaging technique, a high-resolution x-ray phase contrast tomography of an insect is presented.

Authors:
; ; ; ; ; ;  [1];  [2];  [3]
  1. Siemens AG, Corporate Technology, 81739 Munich, Germany and Physik Department, Technische Universitaet Muenchen, 85747 Garching (Germany)
  2. (Germany)
  3. (Switzerland)
Publication Date:
OSTI Identifier:
20971949
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 22; Other Information: DOI: 10.1063/1.2743928; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; COMPUTERIZED TOMOGRAPHY; DIFFRACTION GRATINGS; INSECTS; INTERFEROMETERS; SPATIAL RESOLUTION; X RADIATION; X-RAY SOURCES; X-RAY TUBES

Citation Formats

Engelhardt, Martin, Baumann, Joachim, Schuster, Manfred, Kottler, Christian, Pfeiffer, Franz, Bunk, Oliver, David, Christian, Siemens AG, Corporate Technology, 81739 Munich, and Paul Scherrer Institut, 5232 Villigen PSI. High-resolution differential phase contrast imaging using a magnifying projection geometry with a microfocus x-ray source. United States: N. p., 2007. Web. doi:10.1063/1.2743928.
Engelhardt, Martin, Baumann, Joachim, Schuster, Manfred, Kottler, Christian, Pfeiffer, Franz, Bunk, Oliver, David, Christian, Siemens AG, Corporate Technology, 81739 Munich, & Paul Scherrer Institut, 5232 Villigen PSI. High-resolution differential phase contrast imaging using a magnifying projection geometry with a microfocus x-ray source. United States. doi:10.1063/1.2743928.
Engelhardt, Martin, Baumann, Joachim, Schuster, Manfred, Kottler, Christian, Pfeiffer, Franz, Bunk, Oliver, David, Christian, Siemens AG, Corporate Technology, 81739 Munich, and Paul Scherrer Institut, 5232 Villigen PSI. Mon . "High-resolution differential phase contrast imaging using a magnifying projection geometry with a microfocus x-ray source". United States. doi:10.1063/1.2743928.
@article{osti_20971949,
title = {High-resolution differential phase contrast imaging using a magnifying projection geometry with a microfocus x-ray source},
author = {Engelhardt, Martin and Baumann, Joachim and Schuster, Manfred and Kottler, Christian and Pfeiffer, Franz and Bunk, Oliver and David, Christian and Siemens AG, Corporate Technology, 81739 Munich and Paul Scherrer Institut, 5232 Villigen PSI},
abstractNote = {Differential x-ray phase contrast imaging using a grating interferometer was combined with a magnifying cone beam geometry using a conventional microfocus x-ray tube. This brings the advantages of a magnifying cone beam setup, namely, a high spatial resolution in the micron range and the possibility of using an efficient, low resolution detector, into differential phase contrast imaging. The authors present methodical investigations which show how the primary measurement signal depends on the magnification factor. As an illustration of the potential of this quantitative imaging technique, a high-resolution x-ray phase contrast tomography of an insect is presented.},
doi = {10.1063/1.2743928},
journal = {Applied Physics Letters},
number = 22,
volume = 90,
place = {United States},
year = {Mon May 28 00:00:00 EDT 2007},
month = {Mon May 28 00:00:00 EDT 2007}
}
  • A refractive x-ray lens was characterized using a magnifying cone beam setup for differential phase contrast imaging in combination with a microfocus x-ray tube. Thereby, the differential and the total phase shift of x rays transmitted through the lens were determined. Lens aberrations have been characterized based on these refractive properties.
  • Phase-contrast methods increase contrast, detail, and selectivity in x-ray imaging. Present compact x-ray sources do not provide the necessary spatial coherence with sufficient power to allow the laboratory-scale high-resolution phase-contrast imaging with adequate exposure times. In this letter, the authors demonstrate phase-contrast imaging with few-micron detail employing a compact {approx}6.5 {mu}m spot liquid-metal-jet-anode high-brightness microfocus source. The 40 W source is operated at more than ten times higher electron-beam power density than present microfocus sources and is shown to provide sufficient spatial coherence as well as scalability to high power, thereby enabling the application of phase-contrast x-ray imaging with shortmore » exposure times in clinics and laboratories.« less
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  • A general treatment of x-ray image formation by direct Fresnel diffraction with partially coherent hard x rays is presented. Contrast and resolution are the criteria used to specify the visibility of an image, which depend primarily on the spatial coherence of the illumination and the distance from object to the image, with chromatic coherence of lesser importance. The dependence of the quality of phase-contrast images on the parameters of in-line imaging configuration is described quantitatively. The influence of spatial coherence of hard x-ray source on the imaging quality is also discussed based on the partially coherent direct Fresnel diffraction phase-contrastmore » imaging theory. Experimental results are also presented for phase-contrast x-ray images with partially coherent hard x rays.« less