在大尺寸板状构件成像方面,计算机分层成像(CL)系统具有独特优势。提出并研究了相对平行直线扫描计算机分层成像(PTCL)系统,应用三维解析重建(FDK)算法对该系统进行了图像重建。受制于探测器尺寸,该系统只能采集物体感兴趣区域投影,因此引入基于图像全变差最小化的同时代数迭代重建(SART+TV)算法对物体进行成像。数值仿真实验和实际实验研究表明,FDK和本文算法均能实现系统图像重建,相比于FDK算法,本文算法能从截断的感兴趣区域获得高质量的重建图像。从而验证了系统的可行性。

The computed laminography (CL) system has a unique advantage in aspects of large and plate-like objects imaging. We propose the parallel translation computed laminography (PTCL) system. Then, aiming at the image reconstruction of the system, the Feldkamp, Davis and Kress (FDK) algorithm is applied in the system. Due to the limited size of the detector, the system can only collect the projections of the region of interest of the object and the the total variation minimization based simultaneous algebraic reconstruction technique (SART+TV) algorithm is introduced into the object imaging. The simulation and experimental results demonstrate that both FDK and proposed method can achieve image reconstruction for PTCL. Compared with the FDK algorithm, the proposed method can reconstruct high-quality images from truncated and region of interest projections. Furtherly, it also demonstrates the feasibility of the system.