Journal papers
Martin Zach; Kuan-Chen Shen; Ruiming Cao; Michael Unser; Laura Waller; Jonathan Dong
Perturbative Fourier ptychographic microscopy for fast quantitative phase imaging Journal Article
In: Opt. Express, vol. 33, no. 18, pp. 38984–38996, 2025.
Abstract | Links | BibTeX | Tags: Computational imaging; Illumination design; Image resolution; Microlens arrays; Phase contrast; Phase imaging
@article{Zach:25,
title = {Perturbative Fourier ptychographic microscopy for fast quantitative phase imaging},
author = {Martin Zach and Kuan-Chen Shen and Ruiming Cao and Michael Unser and Laura Waller and Jonathan Dong},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-33-18-38984},
doi = {10.1364/OE.560811},
year = {2025},
date = {2025-09-01},
journal = {Opt. Express},
volume = {33},
number = {18},
pages = {38984–38996},
publisher = {Optica Publishing Group},
abstract = {In computational phase imaging with a microscope equipped with an array of light emitting diodes as the illumination unit, conventional Fourier ptychographic microscopy achieves high resolution and wide-field reconstructions but is constrained by a lengthy acquisition time. Conversely, differential phase contrast (DPC) offers fast imaging but is limited in resolution. Here, we introduce perturbative Fourier ptychographic microscopy (pFPM). pFPM is an extension of DPC that incorporates dark-field illumination to enable fast, high-resolution, wide-field quantitative phase imaging with few measurements. We interpret DPC as the initial iteration of a Gauss-Newton algorithm with quadratic regularization and generalize it to multiple iterations and more sophisticated regularizers. This broader framework is not restricted to bright-field measurements and allows us to overcome resolution limitations of DPC. We develop tailored dark-field illumination patterns with ring shapes, that align with the perturbative interpretation and lead to an improvement in the quality of reconstruction with respect to other common illumination schemes. Consequently, our methodology combines an enhanced phase reconstruction algorithm with a specialized illumination strategy and offers significant advantages in both imaging speed and resolution.},
keywords = {Computational imaging; Illumination design; Image resolution; Microlens arrays; Phase contrast; Phase imaging},
pubstate = {published},
tppubtype = {article}
}
In computational phase imaging with a microscope equipped with an array of light emitting diodes as the illumination unit, conventional Fourier ptychographic microscopy achieves high resolution and wide-field reconstructions but is constrained by a lengthy acquisition time. Conversely, differential phase contrast (DPC) offers fast imaging but is limited in resolution. Here, we introduce perturbative Fourier ptychographic microscopy (pFPM). pFPM is an extension of DPC that incorporates dark-field illumination to enable fast, high-resolution, wide-field quantitative phase imaging with few measurements. We interpret DPC as the initial iteration of a Gauss-Newton algorithm with quadratic regularization and generalize it to multiple iterations and more sophisticated regularizers. This broader framework is not restricted to bright-field measurements and allows us to overcome resolution limitations of DPC. We develop tailored dark-field illumination patterns with ring shapes, that align with the perturbative interpretation and lead to an improvement in the quality of reconstruction with respect to other common illumination schemes. Consequently, our methodology combines an enhanced phase reconstruction algorithm with a specialized illumination strategy and offers significant advantages in both imaging speed and resolution.