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Signal Retrieval from Non-Sinusoidal Intensity Modulations in X-ray and Neutron Interferometry Using
Simon Pinzek1,2, Alex Gustschin1,2, Tobias Neuwirth3,4
1Chair of Biomedical Physics, Department of Physics, School of Natural Sciences, Technical University of Munich, 85748 Garching, Germany.
Journal of Imaging
|October 22, 2021
Summary
This study introduces a new model for grating-based imaging, improving artifact reduction in phase-contrast and dark-field techniques. The advanced method enhances data processing accuracy for various imaging conditions.
Area of Science:
- Physics
- Medical Imaging
- Materials Science
Background:
- Grating-based imaging systems (GBS) are crucial for phase-contrast and dark-field imaging.
- Conventional GBS analysis relies on sinusoidal intensity modulation models.
- Non-sinusoidal modulations in GBS can lead to processing artifacts.
Purpose of the Study:
- To develop an advanced model for grating-based imaging systems.
- To address artifacts caused by non-sinusoidal intensity modulations.
- To improve the accuracy of extracting transmission, differential-phase shift, and scatter information.
Main Methods:
- Introduced a piecewise-defined periodic polynomial function to model signal formation.
- Modeled convolutions of binary periodic functions.
- Extended the model with an iterative expectation-maximization algorithm for phase-stepping inaccuracies.
Main Results:
- The proposed model successfully processes non-sinusoidal intensity modulations.
- Artifacts commonly seen in conventional processing were significantly reduced.
- The approach demonstrated effectiveness on both simulated and experimental data.
Conclusions:
- The developed model offers a more robust approach to grating-based imaging analysis.
- It enhances the reliability of quantitative phase-contrast and dark-field imaging.
- This method broadens the applicability of GBS to more complex imaging scenarios.
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