Abstract Based on the hybrid frequency-domain (FD) and time-domain (TD) radiative transfer equation (RTE), a novel reconstruction strategy is developed to retrieve the optical parameter fields in the participating medium. The discrete ordinate method is employed to solve the forward FD and TD RTE to simulate the radiative transfer process. The sequential quadratic programming is utilized to solve the inverse problem for obtaining the optical parameters combined with an adjoint method. The Otsu algorithm is applied to the FD reconstructed results to distinguish the target region and the background region. To overcome the ill-posedness of the inverse problem, the generalized Gaussian Markov random field model is employed as the regularization term in the objective function. Various numerical experiments are studied and all results demonstrate that the proposed hybrid reconstruction scheme is suitable for efficient and accurate optical tomography by combining the FD and TD radiative transfer models. Meanwhile, the crosstalk of the ill-posed inverse problem can be alleviated effectively.

中文翻译：

---

基于混合频域和时域辐射传递模型的改进光学层析成像

摘要 基于混合频域（FD）和时域（TD）辐射传递方程（RTE），提出了一种新的重建策略来检索参与介质中的光学参数场。采用离散纵坐标法求解前向FD和TD RTE以模拟辐射传输过程。利用序列二次规划结合伴随法求解获得光学参数的逆问题。对FD重建结果应用Otsu算法来区分目标区域和背景区域。为了克服逆问题的不适定性，在目标函数中采用广义高斯马尔可夫随机场模型作为正则化项。研究了各种数值实验，所有结果表明，通过结合 FD 和 TD 辐射传输模型，所提出的混合重建方案适用于高效和准确的光学断层扫描。同时，可以有效缓解不适定逆问题的串扰。