一种通过有理分式函数的CT成像用X射线能谱获取方法  

A Method of X-ray Energy Spectrum Acquisition for CT Imaging by Rational Fraction Function

作　　者：申利飞[1] 王文清[2] 白林绪[1] 田子建[1] SHEN Li-fei;WANG Wen-qing;BAI Lin-xu;TIAN Zi-jian(School of Electromechanical and Information Engineering,China University of Mining and Technology(Beijing),Beijing 100083 China;Beijing Polytechnic College,Beijing 100042 China)

机构地区：[1]中国矿业大学(北京)机电与信息工程学院,北京100083 [2]北京工业职业技术学院,北京100042

出　　处：《自动化技术与应用》2020年第3期131-133,142,共4页Techniques of Automation and Applications

基　　金：国家自然科学基金资助项目(编号51674269);北京工业职业技术学院重点课题(编号bgzykyz201605、bgzykyz201780z)。

摘　　要：为了提高量多组投影数据中X射线能谱的获取精度,本文构建得到了一种可以对X射线能谱进行间接估计的方法,并采用仿真测试以及对实际数据的分析表明此方法能够满足有效性要求。利用开源软件来开展仿真测试得到了X射线能谱,对140KV电压下的球管穿过1mm的Cu滤波片的能谱进行了仿真,得到加入1mm滤波片的能谱属于待估计能谱。当铝板厚度达到7cm时,穿透率低于5%。对各个厚度的测量点进行了能谱估计,同时利用剩余测量点验证估计谱精度。对多能投影曲线进行拟合产生的测量点,之后对估计谱准确性进行分析,本文方法可以对多能投影曲线上各个厚度采样点进行拟合构造,从而可以达到更高精度。In order to improve the accuracy of X-ray energy spectrum acquisition in multi-group projection data, a method for indirect estimation of X-ray energy spectrum is constructed in this paper, and simulation test and analysis of actual data show that this method could meet the requirements of validity. The X-ray energy spectrum is obtained by using open source software to carry out simulation test. The energy spectrum of the ball tube under 140 KV voltage passing through 1 mm Cu filter is simulated, and the energy spectrum added with 1 mm filter belongs to the energy spectrum to be estimated. When the thickness of aluminum plate reaches 7 cm, the penetration rate is less than 5%. The energy spectrum estimation of the measured points with different thickness is carried out, and the accuracy of the estimation spectrum is verified by using the remaining measurement points. The measured points generated by fitting the multi-energy projection curve are analyzed for the accuracy of the estimated spectrum. In this paper, the method can be used to fit various thickness sampling points on the multi-energy projection curve, so as to achieve higher accuracy.

关 键 词：X射线能谱估计 CT成像 能谱获取 有理分式函数 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]