Posture correction of dual-energy micro-CT system

In the dual-energy micro-CT system, the ideal posture relation is a necessary condition for high-quality imaging. However, existing posture calibration methods are not able to correct all the posture parameters of the dual-energy micro-CT system utilizing the optical coupler detector. To address this issue, we propose a posture correction method based on a single-sided nine-grids phantom. Scanning experiments and projection data reconstruction are conducted to validate the effectiveness of the proposed method. After posture correction, the absolute values of the coordinate offsets of dual-energy projection points in two directions are less than the unit pixel size of the detector. Besides, artifacts in the reconstruction images of both optical paths are reduced, leading to improved accuracy in material discrimination results from reconstruction images. The proposed method can correct all the posture parameters of the optical coupler detector, making it certainly practical for the micro-CT system utilizing the optical coupler detector.