Speckle-based X-ray microtomography via preconditioned Wirtinger flow.

Area of Science:

• Medical Imaging
• Materials Science
• Physics

Background:

• Quantitative phase imaging in X-ray microtomography enhances sensitivity for low atomic number materials.
• Current methods often require extra measurements or assumptions, limiting practical use.

Purpose of the Study:

• To introduce preconditioned Wirtinger flow (PWF) for assumption-free, single-shot quantitative X-ray microtomography.
• To enable accurate phase retrieval with a single X-ray scan, improving applicability.

Main Methods:

• Developed a specialized gradient-based algorithm incorporating an accurate physical model.
• Accounted for partial coherence of the X-ray source.
• Utilized preconditioned Wirtinger flow (PWF) for phase retrieval.

Main Results:

• Demonstrated accurate phase retrieval in a single shot.
• Achieved improved accuracy and spatial resolution compared to conventional speckle tracking.
• Showcased robustness and versatility across various samples.

Conclusions:

• PWF offers a practical solution for quantitative X-ray microtomography without prior assumptions.
• The method is compatible with bench-top sources due to partial coherence consideration.
• PWF significantly advances the field for imaging low atomic number materials.