中国物理B ›› 2021, Vol. 30 ›› Issue (6): 64201-064201.doi: 10.1088/1674-1056/abee08

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Real time high accuracy phase contrast imaging with parallel acquisition speckle tracking

Zhe Hu(胡哲)1,2, Wen-Qiang Hua(滑文强)1,3, and Jie Wang(王 劼)1,3,†   

  1. 1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 SSRF, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
  • 收稿日期:2021-01-21 修回日期:2021-03-09 接受日期:2021-03-12 出版日期:2021-05-18 发布日期:2021-05-20
  • 通讯作者: Jie Wang E-mail:wangjie@zjlab.org.cn
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11675253 and 11505278).

Real time high accuracy phase contrast imaging with parallel acquisition speckle tracking

Zhe Hu(胡哲)1,2, Wen-Qiang Hua(滑文强)1,3, and Jie Wang(王 劼)1,3,†   

  1. 1 Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 SSRF, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
  • Received:2021-01-21 Revised:2021-03-09 Accepted:2021-03-12 Online:2021-05-18 Published:2021-05-20
  • Contact: Jie Wang E-mail:wangjie@zjlab.org.cn
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 11675253 and 11505278).

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.

关键词: phase contrast imaging, near field speckle, grating splitter

Abstract: 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.

Key words: phase contrast imaging, near field speckle, grating splitter

中图分类号:  (Imaging and optical processing)

  • 42.30.-d
42.30.Ms (Speckle and moiré patterns) 42.30.Rx (Phase retrieval)