Review and experimental comparison of speckle-tracking algorithms for X-ray phase contrast imaging

Area of Science:

• Physics
• Optics
• Materials Science

Background:

• X-ray speckles are utilized in diverse applications like imaging, tomography, and ptychography.
• Retrieving phase information from X-ray speckles is crucial for advanced applications.

Purpose of the Study:

• To review and experimentally compare X-ray near-field speckle grain tracking methods.
• To unify concepts and terminology across different speckle tracking algorithms.
• To provide a didactic and accessible guide for a broad audience.

Main Methods:

• Focus on X-ray near-field speckle grains as wavefront markers.
• Numerical methods for phase information retrieval.
• Comparison of common tracking algorithms and their specifications.
• Experimental validation using phantoms and complex samples.

Main Results:

• Performance comparison of various speckle tracking algorithms under different experimental conditions.
• Assessment of image quality and quantitative analysis for different sample types.
• Demonstration of consistent terminology and formalism for speckle tracking methods.

Conclusions:

• X-ray speckle tracking offers a powerful approach for phase retrieval in various X-ray experiments.
• Standardized methods and consistent terminology enhance the accessibility and application of speckle tracking.
• This work provides a foundation for further advancements in X-ray imaging and analysis.