中国物理B ›› 2024, Vol. 33 ›› Issue (7): 78702-078702.doi: 10.1088/1674-1056/ad3dcc
Yuhang Tan(谭雨航)1, Xuebao Cai(蔡学宝)2, Jiecheng Yang(杨杰成)1, Ting Su(苏婷)1, Hairong Zheng(郑海荣)1,3, Dong Liang(梁栋)1,3, Peiping Zhu(朱佩平)4, and Yongshuai Ge(葛永帅)1,3,†
Yuhang Tan(谭雨航)1, Xuebao Cai(蔡学宝)2, Jiecheng Yang(杨杰成)1, Ting Su(苏婷)1, Hairong Zheng(郑海荣)1,3, Dong Liang(梁栋)1,3, Peiping Zhu(朱佩平)4, and Yongshuai Ge(葛永帅)1,3,†
摘要: The low-density imaging performance of a zone plate-based nano-resolution hard x-ray computed tomography (CT) system can be significantly improved by incorporating a grating-based Lau interferometer. Due to the diffraction, however, the acquired nano-resolution phase signal may suffer splitting problem, which impedes the direct reconstruction of phase contrast CT (nPCT) images. To overcome, a new model-driven nPCT image reconstruction algorithm is developed in this study. In it, the diffraction procedure is mathematically modeled into a matrix ${\bm B}$, from which the projections without signal splitting can be generated invertedly. Furthermore, a penalized weighted least-square model with total variation (PWLS-TV) is employed to denoise these projections, from which nPCT images with high accuracy are directly reconstructed. Numerical experiments demonstrate that this new algorithm is able to work with phase projections having any splitting distances. Moreover, results also reveal that nPCT images of higher signal-to-noise-ratio (SNR) could be reconstructed from projections having larger splitting distances. In summary, a novel model-driven nPCT image reconstruction algorithm with high accuracy and robustness is verified for the Lau interferometer-based hard x-ray nano-resolution phase contrast imaging.
中图分类号: (X-ray imaging)