Abstract
IMAGING with hard X-rays is an important diagnostic tool in medicine, biology and materials science. Contact radiography and tomography using hard X-rays provide information on internal structures that cannot be obtained using other non-destructive methods. The image contrast results from variations in the X-ray absorption arising from density differences and variations in composition and thickness of the object. But although X-rays penetrate deeply into carbon-based compounds, such as soft biological tissue, polymers and carbon-fibre composites, there is little absorption and therefore poor image contrast. Here we describe a method for enhancing the contrast in hard X-ray images of weakly absorbing materials by resolving phase variations across the X-ray beam1–4. The phase gradients are detected using diffraction from perfect silicon crystals. The diffraction properties of the crystal determine the ultimate spatial resolution in the image; we can readily obtain a resolution of a fraction of a millimetre. Our method shows dramatic contrast enhancement for weakly absorbing biological and inorganic materials, compared with conventional radiography using the same X-ray energy. We present both bright-field and dark-field phase-contrast images, and show evidence of contrast reversal. The method should have the clinical advantage of good contrast for low absorbed X-ray dose.
Similar content being viewed by others
References
Somenkov, V. A., Tkalich, A. K. & Shil'shtein, S. Sh. Sov. Phys. Tech. Phys. 36, 1309–1311 (1991).
Mitrofanov, N. et al. Soviet Patent No. 1402871 (1986).
Belyaevskaya, E. A., Epfanov, V. P. & Ingal, V. Soviet Patent No. 4934958 (1991); US Patent No. 5319694 (1992).
Wilkins, S. W., Australian Patent Applic. PM0583/93 (1993) & PCT/AU94/00480 (1994).
Zernike, F. Z. Tech. Phys. 16, 454–457 (1935).
Steel, W. H. Interferometory 2nd edn (Cambridge Univ. Press, 1983).
Born, M. & Wolf, E. Principles of Optics 2nd edn (Pergamon, Oxford, 1964).
Hart, M. Rep. Prog. Phys. 34, 435–490 (1971).
Tanner, B. K. & Bowen, D. K. J. Cryst. Growth 126, 1–18 (1993).
Nakayama, K., Hashizume, H., Miyoshi, A., Kikuta, S. & Kohra, K. Z. Naturf. 28A, 632–638 (1973).
Matsushita, T. & Hashizume, H. in Handbook on Synchrotron Radiation Vol. 1 (ed. Koch, E. E.) Ch. 4 (North-Holland, Amsterdam, 1983).
Wilkins, S. W. Proc. R. Soc. 364, 569–589 (1978).
Azároff, L. V. et al. X-Ray Diffraction 180–191 (McGraw-Hill, Sydney, 1974).
Davis, T. J. Acta Cryst. A50, 686–690 (1994).
Authier, A. & Simon, D. Acta Cryst. A24, 517–526 (1968).
Uragami, T. J. phys. Soc. Japan 27, 147–154 (1969).
Afanas'ev, A. M. & Kohn, V. G. Acta Cryst. A27, 421–430 (1971).
Bonse, U. & Hart, M. Appl. Phys. Lett. 6, 155–156 (1965).
Wilkins, S. W. Australian Patent Applic. PM1519/93 (1993) & PCT/AU94/00480 (1994).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Davis, T., Gao, D., Gureyev, T. et al. Phase-contrast imaging of weakly absorbing materials using hard X-rays. Nature 373, 595–598 (1995). https://doi.org/10.1038/373595a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/373595a0
- Springer Nature Limited
This article is cited by
-
Parabolic gratings enhance the X-ray sensitivity of Talbot interferograms
Scientific Reports (2023)
-
On the quantification of sample microstructure using single-exposure x-ray dark-field imaging via a single-grid setup
Scientific Reports (2023)
-
The effect of a variable focal spot size on the contrast channels retrieved in edge-illumination X-ray phase contrast imaging
Scientific Reports (2022)
-
Crystal optics simulations for delineation of the three-dimensional cellular nuclear distribution using analyzer-based refraction-contrast computed tomography
Scientific Reports (2022)
-
Enhanced detection of threat materials by dark-field x-ray imaging combined with deep neural networks
Nature Communications (2022)