Munro Peter R T, Ignatyev Konstantin, Speller Robert D, Olivo Alessandro
Department of Medical Physics and Bioengineering, University College London, London, UK.
Opt Express. 2010 Sep 13;18(19):19681-92. doi: 10.1364/OE.18.019681.
There is currently much interest in developing X-ray Phase Contrast Imaging (XPCI) systems which employ laboratory sources in order to deploy the technique in real world applications. The challenge faced by nearly all XPCI techniques is that of efficiently utilising the x-ray flux emitted by an x-ray tube which is polychromatic and possesses only partial spatial coherence. Techniques have, however, been developed which overcome these limitations. Such a technique, known as coded aperture XPCI, has been under development in our laboratories in recent years for application principally in medical imaging and security screening. In this paper we derive limitations imposed upon source polychromaticity and spatial extent by the coded aperture system. We also show that although other grating XPCI techniques employ a different physical principle, they satisfy design constraints similar to those of the coded aperture XPCI.
目前，人们对开发采用实验室光源的X射线相衬成像（XPCI）系统兴趣浓厚，以便将该技术应用于实际应用中。几乎所有XPCI技术面临的挑战是如何有效利用X射线管发出的多色且仅具有部分空间相干性的X射线通量。然而，已经开发出了克服这些限制的技术。这样一种技术，称为编码孔径XPCI，近年来一直在我们实验室中进行开发，主要应用于医学成像和安全筛查。在本文中，我们推导了编码孔径系统对源多色性和空间范围施加的限制。我们还表明，尽管其他光栅XPCI技术采用不同的物理原理，但它们满足与编码孔径XPCI类似的设计约束。
