锥形束Micro-CT几何校正方法的实现

Realization of geometric calibration method of cone-beam Micro-CT

目的 :通过实现校正方法和设计校正体模,对锥形束Micro-CT系统进行几何校正,以实现高质量锥形束Micro-CT图像重建。方法 :使用特定体模,根据体模在探测器上的投影数据,利用线性拟合、几何关系等推导算法计算出锥形束Micro-CT系统几何位置参数,以实现系统几何校正。计算软件及仿真实验均使用VC++实现。结果:仿真实验表明,该算法具有较高精度,相对误差较小,证明了该校正体模和校正方法的有效性、可行性。结论:应用该校正方法能够准确计算锥形束Micro-CT系统几何位置参数误差,精度较高。通过对几何位置参数误差进行调整,能有效减少重建图像伪影,进一步提高成像分辨力。

Objective To execute geometric calibration and calibration phantom design to realize high-quality cone-beam Micro-CT image reconstruction. Methods The geometrical position parameters of cone-beam Micro-CT system were deduced by the data of the designed phantom projected on the detector by means of linear fitting and geometric relation,so as to realize the geometric calibration of the system.The calculation software and the simulation experiment were achieved by VC＋＋programming language.Results The validity and feasibility of the calibration model and method were proved by the experimental simulation. Conclusion The geometric calibration method can accurately calculate the geometrical position parameter errors of the cone-beam Micro-CT system.It can effectively reduce the artifacts in the reconstructed image and further improve the imaging resolution by adjusting the geometric position parameters.