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- 2016
用单一光源标定光子计数探测器
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Abstract:
光子计数探测器在X光能谱CT成像中应用越来越广泛。受到脉冲堆叠、 电荷共享等物理作用的影响, 目前的光子计数探测器的能量标定方法具有一定的局限性。该文提出了一种只用一个单能光源对探测器进行标定的方法, 通过充分挖掘及利用有限的数据, 运用迭代的方法, 最终确定探测器各阈值所对应的能量。该方法不仅实验量小, 操作简单, 标定结果较准确, 还考虑了对小像素探测器标定有较大影响的电荷共享问题, 且具有普适性, 对其他光子计数探测器的标定也有一定的帮助。
Abstract：Photon counting detectors (PCDs) are important in spectral X-ray imaging and computed tomography (CT) systems. Various PCD energy calibration methods have been developed but have many limitations because of the influences of the pulse pileup, charge sharing and other physical effects. This paper describes a calibration method using only one monochromatic source. An iterative technique is used to fully analyze the data to determine the energy for various thresholds. The method gives good results with fewer tests than other calibration methods. The charge sharing effect is implicitly corrected, which is an important factor in the calibration of small pixel detectors. This method is quite universal and can be used to calibrate other PCDs.
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