The effect of the scattered photons was taken into account and the iterative deduction of the scattered photons was used to amend the scattering effect in the image restoration. The customization of AutoCAD was performed to achieve the three-dimensional arbitrary geometry pretreatment. On the basis of the model, IPOR (Iterative Procedure for image restORation code) was developed. Comparison of the results of IPOR code with those of MCNP shows that the scattering correction method of IPOR outperforms the MC method in terms of much less computing time by more than two orders of magnitude with comparable precision. Furthermore, IPOR code has a very high computational efficiency, and it is more accurate compared with the direct solution without scattering correction.%在客体材料密度重建过程中考虑散射光子的影响,研究了在重建过程中通过迭代扣除散射贡献进行散射修正的重建方法.针对三维任意几何结构问题,利用AutoCAD的二次开发功能实现几何前处理,开发了用于散射量计算的快速光子输运计算程序及基于三维任意几何结构的迭代法图像重建程序(IPOR).通过与蒙特卡罗程序MCNP进行数值比较,可知文中采用的散射修正方法在达到与蒙特卡罗方法相当精度的同时,其计算效率可提高2个数量级.重建计算结果表明,IPOR的重建精度远高于未进行散射修正的直接求解法的重建精度.
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