Single-exposure X-ray phase imaging microscopy with a grating interferometer.

Area of Science:

• Optics
• Materials Science
• Physics

Background:

• Hard X-ray free-electron lasers (XFELs) provide unprecedented temporal resolution for nanoscopic imaging.
• X-ray grating interferometry (XGI) is a phase-sensitive technique suitable for single-exposure imaging.
• XFEL pulse instabilities present challenges for traditional imaging methods.

Purpose of the Study:

• To characterize the single-exposure phase imaging capabilities of XGI at a hard X-ray beamline.
• To compare XGI with propagation-based phase contrast imaging.
• To evaluate quantitativeness, contrast-to-noise ratio, and spatial resolution of XGI.

Main Methods:

• Implementation of XGI at the I13-1 beamline, Diamond Light Source.
• Performance of propagation-based phase contrast imaging for comparison.
• Application of a statistical image reconstruction scheme to XGI data.

Main Results:

• Quantification of phase reconstruction accuracy and contrast-to-noise ratio for single-exposure XGI.
• Assessment of achievable spatial resolution, demonstrating mitigation of previous limitations.
• Successful experimental applicability of XGI demonstrated at a synchrotron facility.

Conclusions:

• Single-exposure XGI is a viable and powerful technique for nanoscopic imaging at XFELs.
• Statistical reconstruction significantly improves spatial resolution and broadens the experimental utility of XGI.
• XGI offers a robust solution for phase-sensitive imaging in the presence of XFEL fluctuations.