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Anisotropic regularization for sparsely sampled and noise-robust Fourier ptychography
Optics Express
|November 14, 2024
Summary
Fourier ptychography (FP) reconstruction is improved with a new algorithm using anisotropic total variation and Tikhonov regularizations. This method enhances image quality under noisy and sparse data conditions, crucial for high-throughput imaging.
Area of Science:
- Computational imaging
- Microscopy
- Image reconstruction
Background:
- Fourier ptychography (FP) offers super-resolution and quantitative phase imaging.
- FP reconstruction is ill-posed with noisy or insufficient data.
- High-throughput imaging demands robust FP reconstruction.
Purpose of the Study:
- To develop a regularized FP reconstruction algorithm for improved performance under challenging conditions.
- To enhance image quality and data recovery in sparse and noisy FP measurements.
Main Methods:
- Proposed a regularized FP reconstruction algorithm.
- Utilized anisotropic total variation (TV) for object function regularization.
- Employed Tikhonov regularization for pupil function.
- Formulated reconstruction using the alternating direction method of multipliers (ADMM).
Main Results:
- Successfully recovered high-quality images from sparsely sampled and noisy measurements.
- Demonstrated effective noise suppression and edge preservation with TV regularization.
- Retrieved accurate amplitude and phase images under insufficient sampling.
- Outperformed other FP reconstruction algorithms under harsh conditions.
Conclusions:
- The proposed regularized FP algorithm significantly improves reconstruction quality.
- Anisotropic TV and Tikhonov regularizations are effective for noisy and sparse FP data.
- The method is validated on real experimental FP microscopy images, showing practical utility.
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