a-Si FPD在闪光X光照相中的应用可行性实验研究

Experimental Study of the Application Feasibility of a-Si FPD for Flash x-ray Radiography

非晶硅平板探测器(a-Si Flat Panel Detector)已在无损检测、医疗领域的连续式X光照相中得到了广泛应用,但在脉冲式(ns量级)闪光X光照相中的应用可行性及成像性能却未见报导。本文利用Varian公司生产的PaxScan 2520 HE型非晶硅平板探测器为接收系统,在450keV脉冲X光机上开展了闪光照相实验,考察了该探测器的应用可行性,测量了其探测灵敏度、像质计灵敏度、线扩散函数(LSF)及调制传递函数(MTF)。实验结果表明该探测器可应用于闪光X光照相,且探测灵敏度较高,空间分辨率较好,是一种有前景的闪光X光照相图像接收系统。

Although a-Si FPD has proven to be quick and efficient for producing high quality digital images for continuous x-ray radiography, it has not been reported about the application feasibility of a-Si FPD in flash （from several to tens nanoseconds） x-ray radiography. In this paper, an a-Si FPD （Varian PaxScan 2520 HE） was used as imaging system in 450keV flash x-ray radiography to investigate the application feasibility. The detecting sensitivity was evaluated by step method. Imaging Quality Index （IQI） sensitivity was measured. Line spread function （ISF） and modulation transfer function （MTF） were acquired by knife-edge method and Fourier transform. The results demonstrated that a-Si FPD is an attractive detector for flash x-ray radiography with quality images.