A correction was developed for a misaligned cone beam computed tomography (CT) system. The cone beam CT system was modeled as a pin-hole camera. A camera imaging model was used to describe the mapping information between the 3D voxels and the 2D projection. This information was integrated into the cone beam CT reconstruction to correct the misaligned cone beam CT image. A computing camera calibration technique was used to build the imaging model. This technique is reliable and accurate. Simulations and real system tests show that this method effectively corrects geometric misalignments during cone beam CT reconstruction.
王梦蛟,丁辉,王广志. 基于相机模型的锥束CT重建误差校正[J]. 清华大学学报（自然科学版）, 2015, 55(1): 122-127.
Mengjiao WANG,Hui DING,Guangzhi WANG. Misaligned cone beam computed tomography reconstruction based on a camera model. Journal of Tsinghua University(Science and Technology), 2015, 55(1): 122-127.
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