Reconstructive colour X-ray diffraction imaging - a novel TEDDI imaging method
Reconstructive colour X-ray diffraction imaging - a novel TEDDI imaging method
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DOI：
10.1039/b901726g
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发表时间：
2009-01-01
期刊：
影响因子：
4.2
通讯作者：
Barnes, Paul
中科院分区：
文献类型：
--
作者：
Lazzari, Olivier;Jacques, Simon;Barnes, Paul
层析能量色散衍射成像（TEDDI）能够利用记录的全方位X射线信号（衍射、荧光、散射、背景），对块状物体内部进行独特的非破坏性映射。与光学成像类似，分散在X射线波长中的各种各样的特征（结构、成分、取向、应变）可以被提取并进行颜色编码以帮助解释。这种方法的最终目标是实现实时高清晰度彩色X射线衍射成像，时间尺度为秒，这样人们就能够“看到”光学不透明的设备，并解开材料化学发生的空间/时间演化。这将对许多科学领域产生强烈影响，但目前这一目标存在两个障碍：数据采集速度（2D扫描目前需要几分钟到几小时）和X射线采样体积空间失真导致的图像清晰度损失。在这里，我们提出了一个数据收集方案和重建例程，克服了后者的障碍，并已成功地应用到一个幻影测试对象和真实的材料系统，如碳酸化水泥块。这些程序可以立即转移到多能量色散探测器阵列的有前途的技术，计划提供另一个突破，即数据采集速率的一到两个数量级的改进，这将需要实现实时高清晰度彩色X射线衍射成像。
Tomographic Energy-Dispersive Diffraction Imaging (TEDDI) enables a unique non-destructive mapping of the interior of bulk objects, exploiting the full range of X-ray signals (diffraction, fluorescence, scattering, background) recorded. By analogy to optical imaging, a wide variety of features (structure, composition, orientation, strain) dispersed in X-ray wavelengths can be extracted and colour-coded to aid interpretation. The ultimate aim of this approach is to realise real-time high-definition colour X-ray diffraction imaging, on the timescales of seconds, so that one will be able to 'look inside' optically opaque apparatus and unravel the space/time-evolution of the materials chemistry taking place. This will impact strongly on many fields of science but there are currently two barriers to this goal: speed of data acquisition (a 2D scan currently takes minutes to hours) and loss of image definition through spatial distortion of the X-ray sampling volume. Here we present a data-collection scenario and reconstruction routine which overcomes the latter barrier and which has been successfully applied to a phantom test object and to real materials systems such as a carbonating cement block. These procedures are immediately transferable to the promising technology of multi-energy-dispersive-detector-arrays which are planned to deliver the other breakthrough, that of one-two orders of magnitude improvement in data acquisition rates, that will be needed to realise real-time high-definition colour X-ray diffraction imaging.