PURPOSE Biological soft tissues encountered in clinical and preclinical imaging mainly consists of atoms of light elements with low atomic numbers and their elemental composition is nearly uniform with little density variation. Hence, x-ray attenuation contrast is relatively poor and cannot achieve satisfactory sensitivity and specificity. In contrast, x-ray phase-contrast provides a new mechan...

This paper summarizes the theory of Fresnel diffraction by plane rectangular and circular apertures with a view toward numerical computations. Approximations found in the earlier literature, and now obsolete, have been eliminated and replaced by algorithms suitable for use on a personal computer.

We propose an efficient algorithm using layered stereogram based inverse Fresnel diffraction for 3-D computer-generated holograms. Experiments demonstrate the proposed method can reconstruct quality 3-D images with accurate depth cues. OCIS codes: (090.1760) Computer holography; (090.2870) Holographic display.

In the near field regime of diffractive atom optics, amplitude corrugations of the de Broglie wave front are important and can lead to interesting effects. One class of near field phenomena is the formation of Fresnel images. We study this effect and possible applications in atom lithography using wave packet simulations. Diffraction of atoms most clearly demonstrates the ultimate wave characte...

Propagation within optical waveguides is re-examined in terms of diffraction-free propagation. The concept of the general diffraction-free mode is introduced. It is suggested that the optimised photonic bandgap waveguide must generate such a mode for loss-free propagation to be achieved. The invention of the ‘‘Fresnel’’ waveguide is described. 2002 Elsevier Science B.V. All rights reserved. Whe...