Image analysis of CdZnTe detectors for digital radiography

In this study, the temporal response of a planar Cd_1-xZn_xTe sample at each frequency of a scanning square-wave test pattern, have been measured. The experimental arrangement, although is not offered for large field-of-view imaging applications, offers potential capabilities for feasibility studies, research and evaluation of the temporal response and noise characteristics of a Cd_1-xZn_xTe detector, for fast digital radiographic and CT applications. The dependence of the modulation transfer function (MTF(f)) of the experimental x-ray detector system of both the applied electric field and thickness has been determined experimentally. The results of this study indicate that the overall MTF(f) of the CdZnTe detector system improves both with increasing applied bias voltage and decreasing the detector thickness. Further improvement of the geometrical and signal collection parameters will improve the spatial resolution of the x-ray system significantly.