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Phase retrieval via iterative spatial-frequency masking for ptychography
Optics Letters
|September 16, 2025
Summary
We developed a new ptychographic phase retrieval method called PRISM. It improves reconstruction quality and robustness to noise and low overlap, overcoming key challenges in imaging.
Area of Science:
- Computational imaging
- Phase retrieval algorithms
- Diffractive imaging techniques
Background:
- Ptychographic phase retrieval is crucial for high-resolution imaging but suffers from convergence issues, noise sensitivity, and low overlap ratios.
- Existing methods struggle to balance reconstruction quality with robustness under suboptimal conditions.
Purpose of the Study:
- To introduce a novel reconstruction framework, phase retrieval via iterative spatial-frequency masking for ptychography (PRISM).
- To enhance convergence, noise robustness, and overlap ratio tolerance in ptychographic reconstructions.
- To improve overall reconstruction quality in challenging imaging scenarios.
Main Methods:
- PRISM decomposes the reconstruction process into a frequency-progressive optimization.
- It leverages the inherent structure of frequency information for iterative refinement.
- The framework was validated using both simulated data and experimental measurements.
Main Results:
- PRISM demonstrated significantly improved convergence performance compared to traditional methods.
- The method showed enhanced robustness against noise and low overlap ratios.
- Reconstruction quality was superior, particularly under challenging low-overlap and high-noise conditions.
Conclusions:
- PRISM offers a novel and effective approach to ptychographic phase retrieval.
- The frequency-progressive strategy overcomes critical limitations of existing methods.
- PRISM provides a robust solution for high-quality imaging even in difficult experimental settings.
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