摘要
根据CdZnTe(CZT)晶体的辐射探测理论,搭建了CZT像素阵列探测系统。采用241Am源研究了2×2像素阵列特性,得到了59.5keV能量γ射线能谱,最高能量分辨率为14.6%,并且各个像素性能差异明显,特别是边缘像素出现低能道区域计数增多,谱线向低能方向轻微漂移。为优化辐射成像,对实验数据作了进一步研究。结果表明,晶体内部不均匀的电场是造成各个像素性能偏差,和边缘像素谱漂移的主要原因。在成像过程中可以通过针对性的补偿加以修正,从而提高探测器有效成像面积,优化成像质量。
A pixellated CdZnTe detection system has been designed and fabricated.By using the 2×2 pixellated detector,the 59.5 keV gamma spectra has been gotten based on the 241Am source,the highest energy resolution is 14.6%,and the spectrum of the corner pixel has a little drift to the low energy region.In order to optimize radiation imaging,the data from the testing is investigated and analyzed.It shows that the uniformity of electric field within the crystal is the major reason making the differences among the different pixels and the spectrum drifting.However,the distortion can be weakened by compensation aiming to overcome the defect of the CdZnTe detectors.The quality of image on edge region of the detector can be improved by raising the valid area of CdZnTe detector.
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2010年第5期639-643,共5页
Journal of Optoelectronics·Laser
基金
国家自然科学基金资助项目(10876044)
