Physics-constrained reconstruction for super-resolution ptychographic structured modulation microscopy.

Area of Science:

• Optics and Photonics
• Biomedical Imaging
• Computational Microscopy

Background:

• Conventional optical microscopy is limited by diffraction, discarding phase information crucial for quantitative imaging.
• Existing ptychographic methods with diffuser modulation struggle with misalignment, noise, and weak priors, leading to image degradation.

Purpose of the Study:

• To present a novel physics-constrained inversion framework for quantitative phase imaging.
• To enhance spatial resolution beyond the diffraction limit using diffuser modulation and coherent propagation.

Main Methods:

• Developed a unified forward model incorporating diffuser modulation and coherent propagation.
• Implemented physics-constrained inversion with anisotropic complex regularization for stable convergence.
• Enforced amplitude-residual fidelity for robust reconstruction.

Main Results:

• Demonstrated robustness to lateral misregistration and additive Gaussian noise.
• Achieved stable reconstruction fidelity with up to ~61% sampling reduction.
• Enhanced spatial resolution by 1.26× compared to ePIE, surpassing the diffraction limit by 2.16×.

Conclusions:

• The proposed framework significantly improves spatial resolution and image quality in optical microscopy.
• It enables sharper reconstruction of cellular structures with reduced artifacts, even under challenging conditions.
• This method offers a powerful tool for quantitative phase imaging beyond conventional limitations.