中国物理B ›› 2021, Vol. 30 ›› Issue (6): 64201-064201.doi: 10.1088/1674-1056/abee08
Zhe Hu(胡哲)1,2, Wen-Qiang Hua(滑文强)1,3, and Jie Wang(王 劼)1,3,†
Zhe Hu(胡哲)1,2, Wen-Qiang Hua(滑文强)1,3, and Jie Wang(王 劼)1,3,†
摘要: X-ray speckle tracking based methods can provide results with best reported angular accuracy up to 2 nrad. However, duo to the multi-frame requirement for phase retrieval and the possible instability of the x-ray beam, mechanical and background vibration, the actual accuracy will inevitably be degraded by these time-dependent fluctuations. Therefore, not only spatial position, but also temporal features of the speckle patterns need to be considered in order to maintain the superiority of the speckle-based methods. In this paper, we propose a parallel acquisition method with advantages of real time and high accuracy, which has potential applicability to dynamic samples imaging as well as on-line beam monitoring. Through simulations, we demonstrate that the proposed method can reduce the phase error caused by the fluctuations to 1% at most compared with current speckle tracking methods. Meanwhile, it can keep the accuracy deterioration within 0.03 nrad, making the high theoretical accuracy a reality. Also, we find that waveforms of the incident beam have a little impact on the phase retrieved and will not influence the actual accuracy, which relaxes the requirements for speckle-based experiments.
中图分类号: (Imaging and optical processing)