Phase and absorption retrieval using incoherent X-ray sources

X-ray phase contrast imaging has overcome the limitations of X-ray absorption imaging in many fields. Particular effort has been directed towards developing phase retrieval methods: These reveal quantitative information about a sample, which is a requirement for performing X-ray phase tomography, allows material identification and better distinction between tissue types, etc. Phase retrieval seems impossible with conventional X-ray sources due to their low spatial coherence. In the only previous example where conventional sources have been used, collimators were employed to produce spatially coherent secondary sources. We present a truly incoherent phase retrieval method, which removes the spatial coherence constraints and employs a conventional source without aperturing, collimation, or filtering. This is possible because our technique, based on the pixel edge illumination principle, is neither interferometric nor crystal based. Beams created by an X-ray mask to image the sample are smeared due to the incoherence of the source, yet we show that their displacements can still be measured accurately, obtaining strong phase contrast. Quantitative information is extracted from only two images rather than a sequence as required by several coherent methods. Our technique makes quantitative phase imaging and phase tomography possible in applications where exposure time and radiation dose are critical. The technique employs masks which are currently commercially available with linear dimensions in the tens of centimeters thus allowing for a large field of view. The technique works at high photon energy and thus promises to deliver much safer quantitative phase imaging and phase tomography in the future.

[1]  F Arfelli,et al.  An innovative digital imaging set-up allowing a low-dose approach to phase contrast applications in the medical field. , 2001, Medical physics.

[2]  Ziyu Wu,et al.  Low-dose, simple, and fast grating-based X-ray phase-contrast imaging , 2010, Proceedings of the National Academy of Sciences.

[3]  Robert D. Speller,et al.  Coded apertures allow high-energy x-ray phase contrast imaging with laboratory sources , 2011 .

[4]  Tokiko Endo,et al.  A Comparison between Film-Screen Mammography and Full-Field Digital Mammography Utilizing Phase Contrast Technology in Breast Cancer Screening Programs , 2008, Digital Mammography / IWDM.

[5]  Gabor T. Herman,et al.  Image reconstruction from projections : the fundamentals of computerized tomography , 1980 .

[6]  R. Speller,et al.  A coded-aperture technique allowing x-ray phase contrast imaging with conventional sources , 2007 .

[7]  Atsushi Momose,et al.  Demonstration of X-Ray Talbot Interferometry , 2003 .

[8]  R D Speller,et al.  Effects of signal diffusion on x-ray phase contrast images. , 2011, The Review of scientific instruments.

[9]  A. A. Fosbinder.  X-ray interactions , 2002 .

[10]  S. Wilkins,et al.  Hard x-ray quantitative non-interferometric phase-contrast microscopy , 1999 .

[11]  A. Snigirev,et al.  On the possibilities of x-ray phase contrast microimaging by coherent high-energy synchrotron radiation , 1995 .

[12]  Timur E. Gureyev,et al.  Quantitative diffraction-enhanced x-ray imaging of weak objects , 2004 .

[13]  E. Pisano,et al.  Diffraction enhanced x-ray imaging. , 1997, Physics in medicine and biology.

[14]  Tetsuya Yuasa,et al.  DIGITAL MAMMOGRAPHY WITH SYNCHROTRON RADIATION , 1998 .

[15]  S. Wilkins,et al.  Phase-contrast imaging of weakly absorbing materials using hard X-rays , 1995, Nature.

[16]  P. Meystre.  Introduction to the Theory of Coherence and Polarization of Light , 2007 .

[17]  B. L. Henke,et al.  X-Ray Interactions: Photoabsorption, Scattering, Transmission, and Reflection at E = 50-30,000 eV, Z = 1-92 , 1993 .

[18]  T. Gureyev,et al.  Phase retrieval using coherent imaging systems with linear transfer functions , 2004 .

[19]  P. Munro,et al.  Noninterferometric phase-contrast images obtained with incoherent x-ray sources. , 2011, Applied optics.

[20]  Alessandro Olivo,et al.  Source size and temporal coherence requirements of coded aperture type x-ray phase contrast imaging systems. , 2010, Optics express.

[21]  T. R. Fewell,et al.  Molybdenum, rhodium, and tungsten anode spectral models using interpolating polynomials with application to mammography. , 1997, Medical physics.

[22]  R. Lewis,et al.  Medical phase contrast x-ray imaging: current status and future prospects. , 2004, Physics in medicine and biology.

[23]  E. Vallazza,et al.  A single-photon counting “edge-on” silicon detector for synchrotron radiation mammography , 2009 .

[24]  Timur E. Gureyev,et al.  Refracting Röntgen’s rays: Propagation-based x-ray phase contrast for biomedical imaging , 2009 .

[25]  Kentaro Uesugi,et al.  X-ray phase, absorption and scatter retrieval using two or more phase contrast images. , 2010, Optics express.

[26]  Emilio Quaia,et al.  Clinical mammography at the SYRMEP beam line , 2007 .

[27]  Alessandro Olivo,et al.  The relationship between wave and geometrical optics models of coded aperture type x-ray phase contrast imaging systems. , 2010, Optics express.

[28]  O. Bunk,et al.  Phase retrieval and differential phase-contrast imaging with low-brilliance X-ray sources , 2006 .

[29]  P. Cloetens,et al.  Holotomography: Quantitative phase tomography with micrometer resolution using hard synchrotron radiation x rays , 1999 .

[30]  L. Mandel,et al.  Optical Coherence and Quantum Optics , 1995 .

[31]  D. Vine,et al.  Analyzer-based phase contrast imaging and phase retrieval using a rotating anode x-ray source , 2007 .

[32]  A Olivo,et al.  Modelling of a novel x-ray phase contrast imaging technique based on coded apertures , 2007, Physics in medicine and biology.

[33]  Franz Pfeiffer,et al.  X-ray phase imaging with a grating interferometer. , 2005, Optics express.