脉冲X射线管研制及其成像应用研究  

Research and Imaging Application of Pulsed X-Ray Tubes

作　　者：谭承君 TAN Cheng-jun(Accelerator Laboratory,Department of Engineering Physics,Tsinghua University,Beijing 100084,China;Key Laboratory of Particle&Radiation Imaging(Tsinghua University),Ministry of Education,Beijing 100084,China)

机构地区：[1]清华大学工程物理系加速器实验室,北京100084 [2]粒子技术与辐射成像教育部重点实验室,北京100084

出　　处：《真空电子技术》2023年第6期17-22,共6页Vacuum Electronics

摘　　要：X射线管在安全检查和无损检测领域具有广泛的应用,传统X射线管工作时都是直流出束,本文研究的脉冲X射线管可以根据使用需求,触发射线管发射脉冲X射线,在脉冲持续期间提供高出直流射线源几倍到十倍的X射线剂量。脉冲X射线管选择钡钨阴极作为电子发射体,并在钡钨阴极前放置栅控电极,实现对电子束的控制。脉冲X射线管耐压225 kV,焦点小于2.0 mm,脉冲电流可达70 mA以上,脉宽20~5000μs连续可调。图像实验结果表明,由该脉冲射线源组成的成像系统具有良好的时间分辨率和空间分辨率,在获得相同图像指标的情况下,使用脉冲射线管所需的射线剂量约为直流射线管的40%,这可以降低被检物体的吸收剂量,同时减小设备体积、重量和辐射防护压力。X-ray tubes are widely used in safety inspection and nondestructive testing.The traditional X-ray tube usually generates continuously X-ray.The pulsed X-ray tube described in this paper can generate pulsed X-rays according to user demand,and provide X-ray dose several to ten times higher than that of the continuous X-ray tube during the pulse duration.A dispenser Ba-W cathode is selected as the electron emitter in the pulsed X-ray tube,and a grid electrode is placed in front of the Ba-W cathode to control the electron beam emission.The nominal tube voltage is 225 kV,the maximum pulse current is more than 70 mA,the focus spot is less than 2.0 mm,and the pulse width is adjustable from 20 to 5000μs.The imaging experiment results show that the imaging system composed of the pulsed X-ray tube has better temporal resolution and spatial resolution.Under the condition of obtaining the same image index,the ray dose required by using the pulsed ray tube is about 40%of that of the continuously ray tube,which can reduce the absorbed dose of the tested object,and reduce the size,weight and radiation protection pressure of the imaging equipment.

关 键 词：脉冲X射线管 栅控电子枪 钡钨阴极 X射线成像 

分 类 号：TN14[电子电信—物理电子学]