Phase-contrast imaging of weakly absorbing materials using hard X-rays

Davis, Timothy J.; Gao, Dachao; Gureyev, T. E.; Stevenson, Andrew W.; Wilkins, S. W.

doi:10.1038/373595a0

Cited by 963 publications

(586 citation statements)

References 9 publications

Supporting

Mentioning

580

Contrasting

Unclassified

Order By: Relevance

“…The most usual contrast mechanism is via X-ray attenuation from interactions with electrons in a material, producing twodimensional images of the projected electron density on the detector (imaging the bright-field). Electrons also scatter X-rays which, if collected, can add additional contrast and sensitivity to the projected image (imaging the dark-field) [2][3][4]. By using X-ray diffractometers or spectrometers, the scattered or the emitted radiation can be analysed and exploited to obtain quantitative information about the sample, for example, its crystalline or chemical content [5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Dark-field hyperspectral X-ray imaging

et al. 2014

View full text Add to dashboard Cite

In recent times, there has been a drive to develop nondestructive X-ray imaging techniques that provide chemical or physical insight. To date, these methods have generally been limited; either requiring raster scanning of pencil beams, using narrow bandwidth radiation and/or limited to small samples. We have developed a novel full-field radiographic imaging technique that enables the entire physiochemical state of an object to be imaged in a single snapshot. The method is sensitive to emitted and scattered radiation, using a spectral imaging detector and polychromatic hard X-radiation, making it particularly useful for studying large dense samples for materials science and engineering applications. The method and its extension to three-dimensional imaging is validated with a series of test objects and demonstrated to directly image the crystallographic preferred orientation and formed precipitates across an aluminium alloy friction stir weld section.

show abstract

Section: Introductionmentioning

confidence: 99%

Dark-field hyperspectral X-ray imaging

et al. 2014

View full text Add to dashboard Cite

show abstract

“…This can offer a promising alternative to conventional, attenuation-based x-ray imaging for the visualization of weakly attenuating specimens, due to the fact that phase effects are often stronger in this case 1 . To date, several XPCi modalities have been developed [2][3][4][5][6][7] . The edge illumination (EI) method stands out due to its high phase sensitivity and versatility [8][9][10] .…”

Section: Introductionmentioning

confidence: 99%

A continuous sampling scheme for edge illumination x-ray phase contrast imaging

Hagen

Coan

Bravin

et al. 2015

Journal of Applied Physics

View full text Add to dashboard Cite

We discuss an alternative acquisition scheme for edge illumination (EI) x-ray phase contrast imaging (XPCi) based on a continuous scan of the object, and compare its performance to that of a previously used scheme, which involved scanning the object in discrete steps rather than continuously. By simulating signals for both continuous and discrete methods under realistic experimental conditions, the effect of the spatial sampling rate is analysed with respect to metrics such as image contrast and accuracy of the retrieved phase shift. Experimental results confirm the theoretical predictions.Despite being limited to a specific example, the results indicate that continuous schemes present advantageous features compared to discrete ones. Not only can they be used to speed up the acquisition, but they also prove superior in terms of accurate phase retrieval. The theory and experimental results provided in this study will guide the design of future EI experiments through the implementation of optimized acquisition schemes and sampling rates.

show abstract

“…Another category is analyser-based imaging (ABI), which makes use of the rocking curve of an analyser crystal to develop contrast [10]. A number of algorithms have been developed that enable phase and absorption information to be separated [11][12][13][14][15][16][17].…”

Section: Introductionmentioning

confidence: 99%

Medicine, material science and security: the versatility of the coded-aperture approach

Munro

Endrizzi

Diémoz

et al. 2014

Phil. Trans. R. Soc. A.

View full text Add to dashboard Cite

The principal limitation to the widespread deployment of X-ray phase imaging in a variety of applications is probably versatility. A versatile X-ray phase imaging system must be able to work with polychromatic and non-microfocus sources (for example, those currently used in medical and industrial applications), have physical dimensions sufficiently large to accommodate samples of interest, be insensitive to environmental disturbances (such as vibrations and temperature variations), require only simple system set-up and maintenance, and be able to perform quantitative imaging. The coded-aperture technique, based upon the edge illumination principle, satisfies each of these criteria. To date, we have applied the technique to mammography, materials science, small-animal imaging, non-destructive testing and security. In this paper, we outline the theory of coded-aperture phase imaging and show an example of how the technique may be applied to imaging samples with a practically important scale.

show abstract

Phase-contrast imaging of weakly absorbing materials using hard X-rays

Cited by 963 publications

References 9 publications

Dark-field hyperspectral X-ray imaging

Dark-field hyperspectral X-ray imaging

A continuous sampling scheme for edge illumination x-ray phase contrast imaging

Medicine, material science and security: the versatility of the coded-aperture approach

Contact Info

Product

Resources

About