工业CT大视野扫描的统一形式及其重建算法

A general form of large FOV scan model and reconstruction algorithm for industrial CT

摘要: 工业CT大视野扫描模式包括探测器偏置扫描和转台偏置扫描。实际应用中，大视野扫描通常同时存在探测器偏置和转台偏置。针对上述情况，本文提出了大视野扫描的统一形式，即探测器、转台联合偏置扫描。通过分析投影地址的重复采样次数，本文提出基于Parker函数加权的联合偏置重建算法，并对一个考古文物进行大视野扫描实验进行验证。实验结果表明，本文提出的大视野扫描统一模型及其重建算法切实可行，具有一定的工程实用价值。

Abstract: The scan model for enlarging the FOV of an industrial CT include detector displaced scanning and rotation center displaced scanning. In practice,it is common that both the detector center and rotation center are shifted in a large FOV scan model. In this work,aunified form of large FOV scan model is proposed for the scan with both the detector center and rotation center shifted. A Parker weighting based reconstruction algorithm is also formulated by analyzing the repeated sampling of projections. Experimental result shows that the unified form of large FOV scan model and the proposed reconstruction algorithm is feasible and valuable in practical engineering.