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

  title={Phase-contrast imaging of weakly absorbing materials using hard X-rays},
  author={Timothy J. Davis and Da Chao Gao and Timur E Gureyev and Andrew W. Stevenson and Stephen W. Wilkins},
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… 

Phase retrieval and differential phase-contrast imaging with low-brilliance X-ray sources

X-ray radiographic absorption imaging is an invaluable tool in medical diagnostics and materials science. For biological tissue samples, polymers or fibre composites, however, the use of conventional

Phase-contrast imaging using polychromatic hard X-rays

IN conventional radiography, X-rays which pass through an object along different paths are differentially absorbed, and the intensity pattern of the emerging beam records the distribution of

Fine Biomedical Imaging Using X-Ray Phase-Sensitive Technique

X-ray imaging is widely used for non-destructive observations of the inner structures of samples in many fields, such as biological, clinical, and industrial ones. The transparency of X-rays is much

Quantitative multimodal x-ray tomography: absorption, phase, and darkfield contrast

The basic principles of x-ray image formation in radiography have remained essentially unchanged since R¨ontgen first discovered x-rays over a hundred years ago. The conventional approach relies on

Quantitative methods in phase-contrast x-ray imaging

The proposed technique allows rapid noninvasive characterization of the internal structure of thick optically opaque organic samples and should find wide-ranging applications in clinical radiology and medical research.

Dual energy phase contrast x-ray imaging with Talbot-Lau interferometer

In weakly absorbing materials such as polymers and soft tissue, x-ray phase sensitive imaging methods can provide substantially enhanced contrast compared to classical, absorption based radiography.

Laboratory-based X-ray phase-contrast imaging technique for material and medical science applications.

Low-dose phase contrast x-ray medical imaging

Low absorbing details such as thick nylon wires or thin calcium deposits within breast tissue, invisible with conventional techniques, are detected by means of the proposed phase contrast imaging method.

X-ray refraction-contrast computed tomography images using dark-field imaging optics

If an x-ray beam containing internal information derived from sample soft tissue is incident upon a Laue-case analyzer, the beam will subsequently split into a forwardly diffracted beam and a

Low-dose phase contrast x-ray medical imaging.

Low absorbing details within breast tissue, invisible with conventional techniques, are detected by means of the proposed phase contrast imaging method, and the use of a bending magnet radiation source relaxes the previously reported requirements on source size.



Bragg reflection x ray optics

After a brief summary of the properties of x rays and of materials in the x ray frequency range, the ray optics and microscopic wavefield optics of Bragg reflection in perfect crystals are reviewed.

Dynamical theory of X‐ray diffraction in crystals with defects

Sets of integral equations are obtained that describe the X-ray diffraction in defective crystals. A simple description of defects is suggested both for weakly and strongly distorted regions. In the

X-ray Bragg reflexion from perfect crystals – dependence on geometrical factors with particular regard to the zero-level-of-interaction limit

  • S. Wilkins
  • Mathematics
    Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences
  • 1978
The variation of X-ray Bragg reflexion properties of centro-symmetric perfect crystals (both absorbing and non-absorbing) with thickness and degree of asymmetry of the reflexion is explored

A unified treatment of small‐angle X‐ray scattering, X‐ray refraction and absorption using the Rytov approximation

The Helmholtz wave equation for X-rays in a dielectric medium is solved using the Rytov approximation for the X-ray phase perturbation. It is shown that under appropriate limits the solution yields

Pendellösung Fringes of X-Rays in Bragg Case

The dynamical theory of electron and X-rays for a deformed crystal reported by Takagi is applied to the Bragg case. The transmitted and diffracted waves are represented by the same integral forms as

Use of Asymmetric Dynamical Diffraction of X-rays for Multiple-Crystal Arrangements of the (n1, +n2)Setting

Asymmetric dynamical diffractions of X-rays are successively used for multiple crystals arranged in the (n1 , +n2) setting. Double successive asymetric diffractions of the (n1 , +n2) arrangement give

Application de la théorie dynamique de S. Tagaki au contraste d'un défaut plan en topographie par rayons X. I. Faute d'empilement

Tagaki's dynamical theory of X-ray diffraction by a perfect crystal is described for the two cases of an incident plane-wave and a spherical wave. Emphasis is put on the relation between these two

X-Ray diffraction

This t'e_r_t was prepared as an account of work sponsored by an agency of the United States : Government. Neither the United States Government nor any agency th,_reof, nor any of their *i empl.oyees