大面积、高效率和高空间分辨的伽马成像系统在核辐射诊断、核医学成像、空间科学等领域具有重要的应用前景，CdZnTe像素探测器被认为是高能射线成像技术的重要支撑。本项目拟针对高成像精度、高探测效率等关键技术指标，重点围绕CdZnTe像素探测器的边缘效应和串扰效应，系统开展探测器的设计、制备以及成像算法研究。主要研究内容包括：（1）研究晶体表面处理、电极结构、射线散射等因素对像素探测器边缘效应的影响机理；（2）研究像素探测器电荷串扰机理及其基本物理过程，在此基础上通过中心权重优化算法实现探测器的“亚像素”位置分辨能力；（3）通过晶体表面缺陷态及处理工艺研究解决探测器侧向信号损失及干扰等问题，建立探测器封装、集成与测评体系；（4）结合DOI深度信息提取算法和康普顿散射效应的角度分辨算法实现高分辨伽马射线成像技术。通过本项目的实施，最终研制出高分辨的伽马成像用CdZnTe像素探测器，并实现初步应用。

Gama imaging system, with large area, high efficiency and high space resolution, has shown important application prospects in nuclear diagnostic, nuclear medicine imaging and space science, etc. The high performance CdZnTe crystal serves as the important timbering materials for the development of room temperature high energy γ-ray detection and imaging technique. This project focus on the key specification of high image precision and high efficiency, systemically developing the research on the CdZnTe pixel detector design, preparation and gamma imaging algorithms, considering the edge effect and charge sharing effect of CdZnTe pixel detector. Main research proposals are as follows: (1) Developing a systematic study on the mechanism of surface processing, electrodes structure and γ-ray scattering on the edge effect of pixel detector. (2) An in-depth research will be given on the charge sharing effect and its physical process. Through the optimization of center weighted algorithm, detectors with the capability of sub-pixel positioning will be achieved. (3) Problems like lateral signal loss and interference of detectors will be solved through the investigation of crystal surface defects and processing procedure. Developing the detector packaging, integration and evaluation system. (4) On the basis of the above studies, the high spatial resolution gamma imaging technique will be realized, combining the algorithms of depth of interaction (DOI) extraction and angular resolution based on Compton scattering effect. Through the implementation of this project, we aim to develop the CdZnTe pixel detector for high spatial resolution gamma imaging detector and technique use, and to achieve its primary application.