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Updated: May 11, 2026
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Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
Effects of missing low-frequency information on ptychographic and plane-wave coherent diffraction imaging
Haigang Liu1, Zijian Xu, Xiangzhi Zhang
1Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China.
Applied Optics
|May 15, 2013
Summary
Beamstops (BS) in coherent diffractive imaging (CDI) can hinder image reconstruction. Ptychographic CDI (PCDI) tolerates much larger BS than standard CDI, improving robustness with optimized parameters.
Area of Science:
- Coherent diffractive imaging
- X-ray microscopy
- Diffraction imaging
Background:
- Beamstops (BS) are crucial in coherent diffractive imaging (CDI) for extending detector exposure and capturing high-angle diffraction data.
- However, large beamstops can obscure low-frequency signals, leading to unstable or failed CDI reconstructions.
Purpose of the Study:
- To systematically investigate the impact of beamstop size on image reconstruction quality in both plane-wave CDI and ptychographic CDI (PCDI).
- To identify strategies for mitigating the negative effects of beamstops in PCDI experiments.
Main Methods:
- Conducted comprehensive simulations to analyze the influence of beamstop parameters on image reconstruction.
- Compared the performance of plane-wave CDI and PCDI under varying beamstop conditions.
Main Results:
- Ptychographic CDI demonstrated significantly enhanced robustness, tolerating beamstops at least 20 times larger than plane-wave CDI for comparable imaging quality.
- For PCDI, increased overlap ratio and reduced illumination spot size were found to substantially improve image reconstruction stability in the presence of beamstops.
Conclusions:
- Ptychography offers superior resilience to beamstop artifacts compared to conventional CDI.
- Optimizing overlap ratio and illumination spot size in PCDI is key to maximizing robustness against beamstop effects and enhancing spatial resolution.
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