Publications
Ruiming Cao; Nikita S. Divekar; James K. Nuñez; Srigokul Upadhyayula; Laura Waller
Neural space–time model for dynamic multi-shot imaging Journal Article
In: Nature Methods, pp. 1–6, 2024, ISSN: 1548-7105, (Publisher: Nature Publishing Group).
Abstract | Links | BibTeX | Tags: Imaging, Phase-contrast microscopy, Super-resolution microscopy
@article{cao_neural_2024,
title = {Neural space–time model for dynamic multi-shot imaging},
author = {Ruiming Cao and Nikita S. Divekar and James K. Nuñez and Srigokul Upadhyayula and Laura Waller},
url = {https://www.nature.com/articles/s41592-024-02417-0},
doi = {10.1038/s41592-024-02417-0},
issn = {1548-7105},
year = {2024},
date = {2024-09-24},
urldate = {2024-09-01},
journal = {Nature Methods},
pages = {1--6},
abstract = {Computational imaging reconstructions from multiple measurements that are captured sequentially often suffer from motion artifacts if the scene is dynamic. We propose a neural space–time model (NSTM) that jointly estimates the scene and its motion dynamics, without data priors or pre-training. Hence, we can both remove motion artifacts and resolve sample dynamics from the same set of raw measurements used for the conventional reconstruction. We demonstrate NSTM in three computational imaging systems: differential phase-contrast microscopy, three-dimensional structured illumination microscopy and rolling-shutter DiffuserCam. We show that NSTM can recover subcellular motion dynamics and thus reduce the misinterpretation of living systems caused by motion artifacts.},
note = {Publisher: Nature Publishing Group},
keywords = {Imaging, Phase-contrast microscopy, Super-resolution microscopy},
pubstate = {published},
tppubtype = {article}
}
Tiffany Chien; Ruiming Cao; Fanglin Linda Liu; Leyla A. Kabuli; Laura Waller
Space-time reconstruction for lensless imaging using implicit neural representations Journal Article
In: Opt. Express, vol. 32, no. 20, pp. 35725–35732, 2024.
Abstract | Links | BibTeX | Tags: Computational imaging; Imaging systems; Inverse design; Machine learning; Machine vision; Neural networks
@article{Chien:24,
title = {Space-time reconstruction for lensless imaging using implicit neural representations},
author = {Tiffany Chien and Ruiming Cao and Fanglin Linda Liu and Leyla A. Kabuli and Laura Waller},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-32-20-35725},
doi = {10.1364/OE.530480},
year = {2024},
date = {2024-09-01},
journal = {Opt. Express},
volume = {32},
number = {20},
pages = {35725--35732},
publisher = {Optica Publishing Group},
abstract = {Many computational imaging inverse problems are challenged by noise, model mismatch, and other imperfections that decrease reconstruction quality. For data taken sequentially in time, instead of reconstructing each frame independently, space-time algorithms simultaneously reconstruct multiple frames, thereby taking advantage of temporal redundancy through space-time priors. This helps with denoising and provides improved reconstruction quality, but often requires significant computational and memory resources. Designing effective but flexible temporal priors is also challenging. Here, we propose using an implicit neural representation to model dynamics and act as a computationally tractable and flexible space-time prior. We demonstrate this approach on video captured with a lensless imager, DiffuserCam, and show improved reconstruction results and robustness to noise compared to frame-by-frame methods.},
keywords = {Computational imaging; Imaging systems; Inverse design; Machine learning; Machine vision; Neural networks},
pubstate = {published},
tppubtype = {article}
}
Guanghan Meng; Dekel Galor; Laura Waller; Martin S. Banks
BiPMAP: a toolbox for predicting perceived motion artifacts on modern displays Journal Article
In: Opt. Express, vol. 32, no. 7, pp. 12181–12199, 2024.
Abstract | Links | BibTeX | Tags:
@article{Meng:24,
title = {BiPMAP: a toolbox for predicting perceived motion artifacts on modern displays},
author = {Guanghan Meng and Dekel Galor and Laura Waller and Martin S. Banks},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-32-7-12181},
doi = {10.1364/OE.510985},
year = {2024},
date = {2024-03-01},
urldate = {2024-03-01},
journal = {Opt. Express},
volume = {32},
number = {7},
pages = {12181--12199},
publisher = {Optica Publishing Group},
abstract = {Viewers of digital displays often experience motion artifacts (e.g., flicker, judder, edge banding, motion blur, color breakup, depth distortion) when presented with dynamic scenes. We developed an interactive software tool for display designers that predicts how a viewer perceives motion artifacts for a variety of stimulus, display, and viewing parameters: the Binocular Perceived Motion Artifact Predictor (BiPMAP). The tool enables the user to specify numerous stimulus, display, and viewing parameters. It implements a model of human spatiotemporal contrast sensitivity in order to determine which artifacts will be seen by a viewer and which will not. The tool visualizes the perceptual effects of discrete space-time sampling on the display by presenting side by side the expected perception when the stimulus is continuous compared to when the same stimulus is presented with the spatial and temporal parameters of a prototype display.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Nathan Tessema Ersaro; Cem Yalcin; Liz Murray; Leyla Kabuli; Laura Waller; Rikky Muller
Fast non-iterative algorithm for 3D point-cloud holography Journal Article
In: Opt. Express, vol. 31, no. 22, pp. 36468–36485, 2023.
Abstract | Links | BibTeX | Tags: Diode pumped lasers; Fast Fourier transforms; Image quality; Phase retrieval; Spatial light modulators; Three dimensional imaging
@article{Ersaro:23,
title = {Fast non-iterative algorithm for 3D point-cloud holography},
author = {Nathan Tessema Ersaro and Cem Yalcin and Liz Murray and Leyla Kabuli and Laura Waller and Rikky Muller},
url = {https://opg.optica.org/oe/abstract.cfm?URI=oe-31-22-36468},
doi = {10.1364/OE.498302},
year = {2023},
date = {2023-10-01},
urldate = {2023-10-01},
journal = {Opt. Express},
volume = {31},
number = {22},
pages = {36468--36485},
publisher = {Optica Publishing Group},
abstract = {Recently developed iterative and deep learning-based approaches to computer-generated holography (CGH) have been shown to achieve high-quality photorealistic 3D images with spatial light modulators. However, such approaches remain overly cumbersome for patterning sparse collections of target points across a photoresponsive volume in applications including biological microscopy and material processing. Specifically, in addition to requiring heavy computation that cannot accommodate real-time operation in mobile or hardware-light settings, existing sampling-dependent 3D CGH methods preclude the ability to place target points with arbitrary precision, limiting accessible depths to a handful of planes. Accordingly, we present a non-iterative point cloud holography algorithm that employs fast deterministic calculations in order to efficiently allocate patches of SLM pixels to different target points in the 3D volume and spread the patterning of all points across multiple time frames. Compared to a matched-performance implementation of the iterative Gerchberg-Saxton algorithm, our algorithm’s relative computation speed advantage was found to increase with SLM pixel count, reaching >100,000x at 512 × 512 array format.},
keywords = {Diode pumped lasers; Fast Fourier transforms; Image quality; Phase retrieval; Spatial light modulators; Three dimensional imaging},
pubstate = {published},
tppubtype = {article}
}
Gautam Gunjala; Antoine Wojdyla; Kenneth A. Goldberg; Zhi Qiao; Xianbo Shi; Lahsen Assoufid; Laura Waller
Data-driven modeling and control of an X-ray bimorph adaptive mirror Journal Article
In: Journal of Synchrotron Radiation, vol. 30, no. 1, 2023.
Abstract | Links | BibTeX | Tags: adaptive optics, beamline optics, x ray imaging
@article{Gunjala:tv5041,
title = {Data-driven modeling and control of an X-ray bimorph adaptive mirror},
author = {Gautam Gunjala and Antoine Wojdyla and Kenneth A. Goldberg and Zhi Qiao and Xianbo Shi and Lahsen Assoufid and Laura Waller},
url = {https://doi.org/10.1107/S1600577522011080},
doi = {10.1107/S1600577522011080},
year = {2023},
date = {2023-01-01},
urldate = {2023-01-01},
journal = {Journal of Synchrotron Radiation},
volume = {30},
number = {1},
abstract = {Adaptive X-ray mirrors are being adopted on high-coherent-flux synchrotron and X-ray free-electron laser beamlines where dynamic phase control and aberration compensation are necessary to preserve wavefront quality from source to sample, yet challenging to achieve. Additional difficulties arise from the inability to continuously probe the wavefront in this context, which demands methods of control that require little to no feedback. In this work, a data-driven approach to the control of adaptive X-ray optics with piezo-bimorph actuators is demonstrated. This approach approximates the non-linear system dynamics with a discrete-time model using random mirror shapes and interferometric measurements as training data. For mirrors of this type, prior states and voltage inputs affect the shape-change trajectory, and therefore must be included in the model. Without the need for assumed physical models of the mirror's behavior, the generality of the neural network structure accommodates drift, creep and hysteresis, and enables a control algorithm that achieves shape control and stability below 2nm RMS. Using a prototype mirror and it ex situ metrology, it is shown that the accuracy of our trained model enables open-loop shape control across a diverse set of states and that the control algorithm achieves shape error magnitudes that fall within diffraction-limited performance.},
keywords = {adaptive optics, beamline optics, x ray imaging},
pubstate = {published},
tppubtype = {article}
}
Eric Li; Stuart Sherwin; Gautam Gunjala; Laura Waller
Exceeding the limits of algorithmic self-calibrated aberration recovery in Fourier ptychography Journal Article
In: Opt. Continuum, vol. 2, no. 1, pp. 119–130, 2023.
Abstract | Links | BibTeX | Tags: Computational imaging; Image quality; Imaging systems; Optical aberrations; Phase imaging; Reconstruction algorithms
@article{Li:23,
title = {Exceeding the limits of algorithmic self-calibrated aberration recovery in Fourier ptychography},
author = {Eric Li and Stuart Sherwin and Gautam Gunjala and Laura Waller},
url = {https://opg.optica.org/optcon/abstract.cfm?URI=optcon-2-1-119},
doi = {10.1364/OPTCON.475990},
year = {2023},
date = {2023-01-01},
journal = {Opt. Continuum},
volume = {2},
number = {1},
pages = {119--130},
publisher = {Optica Publishing Group},
abstract = {Fourier ptychographic microscopy is a computational imaging technique that provides quantitative phase information and high resolution over a large field-of-view. Although the technique presents numerous advantages over conventional microscopy, model mismatch due to unknown optical aberrations can significantly limit reconstruction quality. A practical way of correcting for aberrations without additional data capture is through algorithmic self-calibration, in which a pupil recovery step is embedded into the reconstruction algorithm. However, software-only aberration correction is limited in accuracy. Here, we evaluate the merits of implementing a simple, dedicated calibration procedure for applications requiring high accuracy. In simulations, we find that for a target sample reconstruction error, we can image without any aberration corrections only up to a maximum aberration magnitude of $łambda$/40. When we use algorithmic self-calibration, we can tolerate an aberration magnitude up to $łambda$/10 and with our proposed diffuser calibration technique, this working range is extended further to $łambda$/3. Hence, one can trade off complexity for accuracy by using a separate calibration process, which is particularly useful for larger aberrations.},
keywords = {Computational imaging; Image quality; Imaging systems; Optical aberrations; Phase imaging; Reconstruction algorithms},
pubstate = {published},
tppubtype = {article}
}
Joseph D. Malone; Neerja Aggarwal; Laura Waller; Audrey K. Bowden
DiffuserSpec: spectroscopy with Scotch tape Journal Article
In: Opt. Lett., vol. 48, no. 2, pp. 323–326, 2023.
Abstract | Links | BibTeX | Tags: Near infrared radiation; Optical components; Reconstruction algorithms; Speckle patterns; Spectrometers; Spectroscopy
@article{Malone:23,
title = {DiffuserSpec: spectroscopy with Scotch tape},
author = {Joseph D. Malone and Neerja Aggarwal and Laura Waller and Audrey K. Bowden},
url = {https://opg.optica.org/ol/abstract.cfm?URI=ol-48-2-323},
doi = {10.1364/OL.476472},
year = {2023},
date = {2023-01-01},
journal = {Opt. Lett.},
volume = {48},
number = {2},
pages = {323--326},
publisher = {Optica Publishing Group},
abstract = {Computational spectroscopy breaks the inherent one-to-one spatial-to-spectral pixel mapping of traditional spectrometers by multiplexing spectral data over a given sensor region. Most computational spectrometers require components that are complex to design, fabricate, or both. DiffuserSpec is a simple computational spectrometer that uses the inherent spectral dispersion of commercially available diffusers to generate speckle patterns that are unique to each wavelength. Using Scotch tape as a diffuser, we demonstrate narrowband and broadband spectral reconstructions with 2-nm spectral resolution over an 85-nm bandwidth in the near-infrared, limited only by the bandwidth of the calibration dataset. We also investigate the effect of spatial sub-sampling of the 2D speckle pattern on resolution performance.},
keywords = {Near infrared radiation; Optical components; Reconstruction algorithms; Speckle patterns; Spectrometers; Spectroscopy},
pubstate = {published},
tppubtype = {article}
}
Yi Xue; David Ren; Laura Waller
Three-dimensional bi-functional refractive index and fluorescence microscopy (BRIEF) Journal Article
In: Biomed. Opt. Express, vol. 13, no. 11, pp. 5900–5908, 2022.
Abstract | Links | BibTeX | Tags: Digital imaging; Fluorescence microscopy; Image quality; Imaging techniques; Optical imaging; Three dimensional imaging
@article{Xue:22,
title = {Three-dimensional bi-functional refractive index and fluorescence microscopy (BRIEF)},
author = {Yi Xue and David Ren and Laura Waller},
url = {https://opg.optica.org/boe/abstract.cfm?URI=boe-13-11-5900},
doi = {10.1364/BOE.456621},
year = {2022},
date = {2022-11-01},
journal = {Biomed. Opt. Express},
volume = {13},
number = {11},
pages = {5900--5908},
publisher = {Optica Publishing Group},
abstract = {Fluorescence microscopy is a powerful tool for imaging biological samples with molecular specificity. In contrast, phase microscopy provides label-free measurement of the sample’s refractive index (RI), which is an intrinsic optical property that quantitatively relates to cell morphology, mass, and stiffness. Conventional imaging techniques measure either the labeled fluorescence (functional) information or the label-free RI (structural) information, though it may be valuable to have both. For example, biological tissues have heterogeneous RI distributions, causing sample-induced scattering that degrades the fluorescence image quality. When both fluorescence and 3D RI are measured, one can use the RI information to digitally correct multiple-scattering effects in the fluorescence image. Here, we develop a new computational multi-modal imaging method based on epi-mode microscopy that reconstructs both 3D fluorescence and 3D RI from a single dataset. We acquire dozens of fluorescence images, each ‘illuminated’ by a single fluorophore, then solve an inverse problem with a multiple-scattering forward model. We experimentally demonstrate our method for epi-mode 3D RI imaging and digital correction of multiple-scattering effects in fluorescence images.},
keywords = {Digital imaging; Fluorescence microscopy; Image quality; Imaging techniques; Optical imaging; Three dimensional imaging},
pubstate = {published},
tppubtype = {article}
}
Henry Pinkard; Laura Waller
Microscopes are coming for your job Journal Article
In: Nature Methods, pp. 1–2, 2022.
@article{pinkard2022microscopes,
title = {Microscopes are coming for your job},
author = {Henry Pinkard and Laura Waller},
url = {https://www.nature.com/articles/s41592-022-01566-4},
year = {2022},
date = {2022-09-08},
urldate = {2022-01-01},
journal = {Nature Methods},
pages = {1--2},
publisher = {Nature Publishing Group},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Kristina Monakhova
Physics-Informed Machine Learning for Computational Imaging PhD Thesis
EECS Department, University of California, Berkeley, 2022.
Abstract | Links | BibTeX | Tags:
@phdthesis{Monakhova:EECS-2022-177,
title = {Physics-Informed Machine Learning for Computational Imaging},
author = {Kristina Monakhova},
url = {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2022/EECS-2022-177.html},
year = {2022},
date = {2022-07-01},
urldate = {2022-07-01},
number = {UCB/EECS-2022-177},
school = {EECS Department, University of California, Berkeley},
abstract = {A key aspect of many computational imaging systems, from compressive cameras to low light photography, are the algorithms used to uncover the signal from encoded or noisy measurements. Some computational cameras encode higher-dimensional information (e.g. different wavelengths of light, 3D, time) onto a 2-dimensional sensor, then use algorithms to decode and recover this high-dimensional information. Others capture measurements that are extremely noisy, or degraded, and require algorithms to extract the signal and make the images usable by people, or by higher-level downstream algorithms. In each case, the algorithms used to decode and extract information from raw measurements are critical and necessary to make computational cameras function. Over the years the predominant methods, classic methods, to recover information from computational cameras have been based on minimizing an optimization problem consisting of a data term and hand-picked prior term. More recently, deep learning has been applied to these problems, but often has no way to incorporate known optical characteristics, requires large training datasets, and results in black-box models that cannot easily be interpreted. In this dissertation, we present physics-informed machine learning for computational imaging, which is a middle ground approach that combines elements of classic methods with deep learning. We show how to incorporate knowledge of the imaging system physics into neural networks to improve image quality and performance beyond what is feasible with either classic or deep methods for several computational cameras. We show several different ways to incorporate imaging physics into neural networks, including algorithm unrolling, differentiable optical models, unsupervised methods, and through generative adversarial networks. For each of these methods, we focus on a different computational camera with unique challenges and modeling considerations. First, we introduce an unrolled, physics-informed network that improves the quality and reconstruction time of lensless cameras, improving these cameras and showing photorealistic image quality on a variety of scenes. Building up on this, we demonstrate a new reconstruction network that can improve the reconstruction time for compressive, single-shot 3D microscopy with spatially-varying blur by 1,600X, enabling interactive previewing of the scene. In cases where training data is hard to acquire, we show that an untrained physics-informed network can improve image quality for compressive single-shot video and hyperspectral imaging without the need for training data. Finally, we design a physics-informed noise generator that can realistically synthesize noise at extremely high-gain, low-light settings. Using this learned noise model, we show how we can push a camera past its typical limit and take photorealistic videos at starlight levels of illumination for the first time. Each case highlights how using physics-informed machine learning can improve computational cameras and push them to their limits.},
keywords = {},
pubstate = {published},
tppubtype = {phdthesis}
}
Michael L. Whittaker; David Ren; Colin Ophus; Yugang Zhang; Laura Waller; Benjamin Gilbert; Jillian F. Banfield
Ion complexation waves emerge at the curved interfaces of layered minerals Journal Article
In: Nature Communications volume , vol. 13, iss. 1, 2022.
Abstract | Links | BibTeX | Tags: tomography
@article{Ion2022,
title = {Ion complexation waves emerge at the curved interfaces of layered minerals},
author = {Michael L. Whittaker and David Ren and Colin Ophus and Yugang Zhang and Laura Waller and Benjamin Gilbert and Jillian F. Banfield },
doi = {https://doi.org/10.1038/s41467-022-31004-0},
year = {2022},
date = {2022-06-13},
urldate = {2022-06-13},
journal = {Nature Communications volume },
volume = {13},
issue = {1},
abstract = {Visualizing hydrated interfaces is of widespread interest across the physical sciences and is a particularly acute need for layered minerals, whose properties are governed by the structure of the electric double layer (EDL) where mineral and solution meet. Here, we show that cryo electron microscopy and tomography enable direct imaging of the EDL at montmorillonite interfaces in monovalent electrolytes with ångstrom resolution over micron length scales. A learning-based multiple-scattering reconstruction method for cryo electron tomography reveals ions bound asymmetrically on opposite sides of curved, exfoliated layers. We observe conserved ion-density asymmetry across stacks of interacting layers in cryo electron microscopy that is associated with configurations of inner- and outer-sphere ion-water-mineral complexes that we term complexation waves. Coherent X-ray scattering confirms that complexation waves propagate at room-temperature via a competition between ion dehydration and charge interactions that are coupled across opposing sides of a layer, driving dynamic transitions between stacked and aggregated states via layer exfoliation.},
keywords = {tomography},
pubstate = {published},
tppubtype = {article}
}
Regina Eckert
Robust 3D Quantitative Phase Imaging PhD Thesis
EECS Department, University of California, Berkeley, 2022.
Abstract | Links | BibTeX | Tags:
@phdthesis{Eckert:EECS-2022-29,
title = {Robust 3D Quantitative Phase Imaging},
author = {Regina Eckert},
url = {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2022/EECS-2022-29.html},
year = {2022},
date = {2022-05-01},
urldate = {2022-05-01},
number = {UCB/EECS-2022-29},
school = {EECS Department, University of California, Berkeley},
abstract = {Biomedical research relies upon quantitative imaging methods to measure functional and structural data about microscopic organisms. Recently-developed quantitative phase imaging (QPI) methods use jointly designed optical and computational systems to recover structural quantitative phase information for biological samples. However, these methods have not seen wide adoption in biological research because the optical systems can be difficult to use and the computational algorithms often require expert operation for consistently high-quality results. QPI systems are usually developed under a computational imaging framework, where the optical measurement system is jointly designed with the computational reconstruction algorithm. Designing QPI systems for robust and practical real-world use is often difficult, however, because each imaging and computational configuration has unique and difficult-to-quantify practical implications for the end-user.
In this dissertation, I present three frameworks for increasing the robustness and practicality of computational imaging systems, and I demonstrate the usefulness of these three frameworks by applying them to 2D and 3D quantitative phase imaging systems. First, algorithmic self-calibration directly recovers imaging system parameters from data measurements, doing away with the need for extensive pre-calibration steps and ensuring greater calibration accuracy for non-ideal, real-world systems. I present a robust and efficient self-calibration algorithm for angled coherent illumination, which has enabled new QPI system designs for 2D Fourier ptychographic microscopy (FPM) and 3D intensity optical diffraction tomography (ODT) that would have otherwise been infeasible. Second, increased measurement diversity better encodes useful information across measurements, which can reduce imaging system complexity, data requirements, and computation time. I present a novel pupil-coded intensity ODT system designed to increase measurement diversity of 3D refractive index (RI) information by including joint illumination- and detection-side coding for improved volumetric RI reconstructions. Finally, physics-based machine learning uses a data-driven approach to directly optimize imaging system parameters, which can improve imaging reconstructions and build intuition for better designs of complicated computational imaging systems. I show results from a physics-based machine learning algorithm to optimize pupil coding masks for 3D RI reconstructions of thick cell clusters in the pupil-coded intensity ODT system.
In addition, I provide practical methods for the design, calibration, and operation of Fourier ptychography, intensity-only ODT, and pupil-coded intensity ODT microscopes to aid in the future development of robust QPI systems. I additionally present a validation of joint system pupil recovery using FPM and a comparison of the accuracy and computational complexity of coherent light propagation models that are commonly used in 3D quantitative phase imaging. I also compare field-based 3D RI reconstructions to intensity-based RI reconstructions, concluding that the proposed pupil-coded intensity ODT system captures similarly diverse phase information to field-based ODT microscopes.
Throughout this work, I demonstrate that by using the frameworks of algorithmic self-calibration, increased system measurement diversity, and physics-based machine learning for computational imaging system design, we can develop more robust quantitative phase imaging systems that are practical for real-world use.},
keywords = {},
pubstate = {published},
tppubtype = {phdthesis}
}
In this dissertation, I present three frameworks for increasing the robustness and practicality of computational imaging systems, and I demonstrate the usefulness of these three frameworks by applying them to 2D and 3D quantitative phase imaging systems. First, algorithmic self-calibration directly recovers imaging system parameters from data measurements, doing away with the need for extensive pre-calibration steps and ensuring greater calibration accuracy for non-ideal, real-world systems. I present a robust and efficient self-calibration algorithm for angled coherent illumination, which has enabled new QPI system designs for 2D Fourier ptychographic microscopy (FPM) and 3D intensity optical diffraction tomography (ODT) that would have otherwise been infeasible. Second, increased measurement diversity better encodes useful information across measurements, which can reduce imaging system complexity, data requirements, and computation time. I present a novel pupil-coded intensity ODT system designed to increase measurement diversity of 3D refractive index (RI) information by including joint illumination- and detection-side coding for improved volumetric RI reconstructions. Finally, physics-based machine learning uses a data-driven approach to directly optimize imaging system parameters, which can improve imaging reconstructions and build intuition for better designs of complicated computational imaging systems. I show results from a physics-based machine learning algorithm to optimize pupil coding masks for 3D RI reconstructions of thick cell clusters in the pupil-coded intensity ODT system.
In addition, I provide practical methods for the design, calibration, and operation of Fourier ptychography, intensity-only ODT, and pupil-coded intensity ODT microscopes to aid in the future development of robust QPI systems. I additionally present a validation of joint system pupil recovery using FPM and a comparison of the accuracy and computational complexity of coherent light propagation models that are commonly used in 3D quantitative phase imaging. I also compare field-based 3D RI reconstructions to intensity-based RI reconstructions, concluding that the proposed pupil-coded intensity ODT system captures similarly diverse phase information to field-based ODT microscopes.
Throughout this work, I demonstrate that by using the frameworks of algorithmic self-calibration, increased system measurement diversity, and physics-based machine learning for computational imaging system design, we can develop more robust quantitative phase imaging systems that are practical for real-world use.
Gautam Gunjala
Towards diffraction-limited short-wavelength imaging systems PhD Thesis
EECS Department, University of California, Berkeley, 2022.
Abstract | Links | BibTeX | Tags:
@phdthesis{Gunjala:EECS-2022-117,
title = {Towards diffraction-limited short-wavelength imaging systems},
author = {Gautam Gunjala},
url = {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2022/EECS-2022-117.html},
year = {2022},
date = {2022-05-01},
urldate = {2022-05-01},
number = {UCB/EECS-2022-117},
school = {EECS Department, University of California, Berkeley},
abstract = {Modern applications of optics, especially those which require shorter wavelengths of light, place ever-increasing demands on the performance of optical tools and systems. Working with extreme ultraviolet, soft x-ray and hard x-ray light poses complex limitations and challenges to diagnosing and maintaining diffraction-limited performance by measuring and controlling optical aberrations. By utilizing computational methods such as optimization and machine learning, we show that some of these limitations can be circumvented without sacrificing accuracy or precision.
In this work, we discuss a method for aberration measurement that is based on an analysis of speckle images acquired in situ. By using a stationary random object, our method eliminates the need for precise manufacturing and alignment of a test target. Moreover, the method provides a full, dense characterization of the optical system under test using relatively few images. The method has been successfully applied to an EUV microscope system, and is shown to be accurate to within λ/180. We also discuss a method for aberration compensation via the characterization and control of an adaptive optical element for x-ray optical systems. Adaptive x-ray optics are a relatively new technology, and our work aims to enable their use within the specifications of synchrotron beamline systems. To this end, we demonstrate the ability to experimentally predict and control the behavior of the glancing-incidence deformable mirror surface to within 2 nm rms, allowing the application of sub-wavelength corrections to an incident wavefront.},
keywords = {},
pubstate = {published},
tppubtype = {phdthesis}
}
In this work, we discuss a method for aberration measurement that is based on an analysis of speckle images acquired in situ. By using a stationary random object, our method eliminates the need for precise manufacturing and alignment of a test target. Moreover, the method provides a full, dense characterization of the optical system under test using relatively few images. The method has been successfully applied to an EUV microscope system, and is shown to be accurate to within λ/180. We also discuss a method for aberration compensation via the characterization and control of an adaptive optical element for x-ray optical systems. Adaptive x-ray optics are a relatively new technology, and our work aims to enable their use within the specifications of synchrotron beamline systems. To this end, we demonstrate the ability to experimentally predict and control the behavior of the glancing-incidence deformable mirror surface to within 2 nm rms, allowing the application of sub-wavelength corrections to an incident wavefront.
Ruiming Cao; Michael Kellman; David Ren; Regina Eckert; Laura Waller
Self-calibrated 3D differential phase contrast microscopy with optimized illumination Journal Article
In: Biomed. Opt. Express, vol. 13, no. 3, pp. 1671–1684, 2022.
Abstract | Links | BibTeX | Tags: Discrete Fourier transforms; Illumination design; Inverse problems; LED lighting; Phase contrast; Three dimensional imaging
@article{Cao:22,
title = {Self-calibrated 3D differential phase contrast microscopy with optimized illumination},
author = {Ruiming Cao and Michael Kellman and David Ren and Regina Eckert and Laura Waller},
url = {http://opg.optica.org/boe/abstract.cfm?URI=boe-13-3-1671},
doi = {10.1364/BOE.450838},
year = {2022},
date = {2022-03-01},
urldate = {2022-03-01},
journal = {Biomed. Opt. Express},
volume = {13},
number = {3},
pages = {1671--1684},
publisher = {OSA},
abstract = {3D phase imaging recovers an object’s volumetric refractive index from intensity and/or holographic measurements. Partially coherent methods, such as illumination-based differential phase contrast (DPC), are particularly simple to implement in a commercial brightfield microscope. 3D DPC acquires images at multiple focus positions and with different illumination source patterns in order to reconstruct 3D refractive index. Here, we present a practical extension of the 3D DPC method that does not require a precise motion stage for scanning the focus and uses optimized illumination patterns for improved performance. The user scans the focus by hand, using the microscope’s focus knob, and the algorithm self-calibrates the axial position to solve for the 3D refractive index of the sample through a computational inverse problem. We further show that the illumination patterns can be optimized by an end-to-end learning procedure. Combining these two, we demonstrate improved 3D DPC with a commercial microscope whose only hardware modification is LED array illumination.},
keywords = {Discrete Fourier transforms; Illumination design; Inverse problems; LED lighting; Phase contrast; Three dimensional imaging},
pubstate = {published},
tppubtype = {article}
}
Yi Xue; Laura Waller; Hillel Adesnik; Nicolas Pégard
Three-dimensional multi-site random access photostimulation (3D-MAP) Journal Article
In: eLife, vol. 2022, no. 11, pp. e73266, 2022.
Links | BibTeX | Tags: 3D imaging
@article{Xue:2022,
title = {Three-dimensional multi-site random access photostimulation (3D-MAP)},
author = {Yi Xue and Laura Waller and Hillel Adesnik and Nicolas Pégard},
doi = {10.7554/eLife.73266},
year = {2022},
date = {2022-02-14},
journal = {eLife},
volume = { 2022},
number = {11},
pages = {e73266},
keywords = {3D imaging},
pubstate = {published},
tppubtype = {article}
}
Vivek Boominathan; Jacob T Robinson; Laura Waller; Ashok Veeraraghavan
Recent advances in lensless imaging Journal Article
In: Optica, vol. 9, no. 1, pp. 1–16, 2022.
Abstract | Links | BibTeX | Tags: Charge coupled devices; Image processing; Imaging systems; Three dimensional imaging; Vertical cavity surface emitting lasers; X ray imaging, lensless imaging
@article{Boominathan:22,
title = {Recent advances in lensless imaging},
author = {Vivek Boominathan and Jacob T Robinson and Laura Waller and Ashok Veeraraghavan},
url = {http://www.osapublishing.org/optica/abstract.cfm?URI=optica-9-1-1},
doi = {10.1364/OPTICA.431361},
year = {2022},
date = {2022-01-01},
journal = {Optica},
volume = {9},
number = {1},
pages = {1--16},
publisher = {OSA},
abstract = {Lensless imaging provides opportunities to design imaging systems free from the constraints imposed by traditional camera architectures. Due to advances in imaging hardware, fabrication techniques, and new algorithms, researchers have recently developed lensless imaging systems that are extremely compact and lightweight or able to image higher-dimensional quantities. Here we review these recent advances and describe the design principles and their effects that one should consider when developing and using lensless imaging systems.},
keywords = {Charge coupled devices; Image processing; Imaging systems; Three dimensional imaging; Vertical cavity surface emitting lasers; X ray imaging, lensless imaging},
pubstate = {published},
tppubtype = {article}
}
Kyrollos Yanny; Kristina Monakhova; Richard W Shuai; Laura Waller
Deep learning for fast spatially varying deconvolution Journal Article
In: Optica, vol. 9, no. 1, pp. 96–99, 2022.
Abstract | Links | BibTeX | Tags: 3D imaging, Hyperspectral imaging; Image quality; Imaging systems; Neural networks; Reconstruction algorithms; Three dimensional reconstruction, spatially-varying
@article{Yanny:22,
title = {Deep learning for fast spatially varying deconvolution},
author = {Kyrollos Yanny and Kristina Monakhova and Richard W Shuai and Laura Waller},
url = {http://www.osapublishing.org/optica/abstract.cfm?URI=optica-9-1-96},
doi = {10.1364/OPTICA.442438},
year = {2022},
date = {2022-01-01},
journal = {Optica},
volume = {9},
number = {1},
pages = {96--99},
publisher = {OSA},
abstract = {Deconvolution can be used to obtain sharp images or volumes from blurry or encoded measurements in imaging systems. Given knowledge of the system's point spread function (PSF) over the field of view, a reconstruction algorithm can be used to recover a clear image or volume. Most deconvolution algorithms assume shift-invariance; however, in realistic systems, the PSF varies laterally and axially across the field of view due to aberrations or design. Shift-varying models can be used, but are often slow and computationally intensive. In this work, we propose a deep-learning-based approach that leverages knowledge about the system's spatially varying PSFs for fast 2D and 3D reconstructions. Our approach, termed MultiWienerNet, uses multiple differentiable Wiener filters paired with a convolutional neural network to incorporate spatial variance. Trained using simulated data and tested on experimental data, our approach offers a 625textminus1600texttimes increase in speed compared to iterative methods with a spatially varying model, and outperforms existing deep-learning-based methods that assume shift invariance.},
keywords = {3D imaging, Hyperspectral imaging; Image quality; Imaging systems; Neural networks; Reconstruction algorithms; Three dimensional reconstruction, spatially-varying},
pubstate = {published},
tppubtype = {article}
}
Sylvain Gigan; Ori Katz; Hilton Barbosa de Aguiar; Esben Andresen; Alexandre Aubry; Jacopo Bertolotti; Emmanuel Bossy; Dorian Bouchet; Josh Brake; Sophie Brasselet; Yaron Bromberg; Hui Cao; Thomas Chaigne; Zhongtao Cheng; Won-Shik Choi; Tomas Cizmar; Meng Cui; Vincent Curtis; Hugo Defienne; Matthias Hofer; Ryoichi Horisaki; Roarke Horstmeyer; Na Ji; Aaron LaViolette; Jerome Mertz; Christophe Moser; Allard P. Mosk; Nicolas Pégard; Rafael Piestun; Sébastien Popoff; Dave Phillips; D Psaltis; Babak Rahmani; Herve Rigneault; Stefan Rotter; Lei Tian; Ivo M Vellekoop; Laura Waller; Lihong V Wang; Timothy Weber; Sheng Xiao; Chris Xu; Alexey Yamilov; Changhuei Yang; Hasan Yılmaz
Roadmap on Wavefront Shaping and deep imaging in complex media Journal Article
In: Journal of Physics: Photonics, 2022.
Abstract | Links | BibTeX | Tags:
@article{10.1088/2515-7647/ac76f9,
title = {Roadmap on Wavefront Shaping and deep imaging in complex media},
author = {Sylvain Gigan and Ori Katz and Hilton Barbosa de Aguiar and Esben Andresen and Alexandre Aubry and Jacopo Bertolotti and Emmanuel Bossy and Dorian Bouchet and Josh Brake and Sophie Brasselet and Yaron Bromberg and Hui Cao and Thomas Chaigne and Zhongtao Cheng and Won-Shik Choi and Tomas Cizmar and Meng Cui and Vincent Curtis and Hugo Defienne and Matthias Hofer and Ryoichi Horisaki and Roarke Horstmeyer and Na Ji and Aaron LaViolette and Jerome Mertz and Christophe Moser and Allard P. Mosk and Nicolas Pégard and Rafael Piestun and Sébastien Popoff and Dave Phillips and D Psaltis and Babak Rahmani and Herve Rigneault and Stefan Rotter and Lei Tian and Ivo M Vellekoop and Laura Waller and Lihong V Wang and Timothy Weber and Sheng Xiao and Chris Xu and Alexey Yamilov and Changhuei Yang and Hasan Yılmaz},
url = {http://iopscience.iop.org/article/10.1088/2515-7647/ac76f9},
year = {2022},
date = {2022-01-01},
urldate = {2022-01-01},
journal = {Journal of Physics: Photonics},
abstract = {The last decade has seen the development of a wide set of tools, such as wavefront shaping, computational or fundamental methods, that allow to understand and control light propagation in a complex medium, such as biological tissues or multimode fibers. A vibrant and diverse community is now working on this field, that has revolutionized the prospect of diffraction-limited imaging at depth in tissues. This roadmap highlights several key aspects of this fast developing field, and some of the challenges and opportunities ahead.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Yonghuan David Ren
Three-Dimensional Phase Contrast Electron Tomography For Multiple Scattering Samples PhD Thesis
EECS Department, University of California, Berkeley, 2021.
Abstract | Links | BibTeX | Tags:
@phdthesis{Ren:EECS-2021-250,
title = {Three-Dimensional Phase Contrast Electron Tomography For Multiple Scattering Samples},
author = {Yonghuan David Ren},
url = {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2021/EECS-2021-250.html},
year = {2021},
date = {2021-12-01},
urldate = {2021-12-01},
number = {UCB/EECS-2021-250},
school = {EECS Department, University of California, Berkeley},
abstract = {Three-dimensional (3D) electron tomography (ET) is used to understand the structure and properties of samples, for applications in chemistry, materials science, and biology. By illuminating the sample at many tilt angles using an electron probe and modelling the image formation model, 3D information can be reconstructed at a resolution beyond the optical diffraction limit. However, as samples become thicker and more scattering, simple image formation models assuming projections or single scattering are no longer valid, causing the reconstruction quality to degrade. In this work, we develop a framework that takes the non-linear image formation process into account by modelling multiple-scattering events between the electron probe and the sample. First, the general acquisition and inverse model to recover multiple-scattering samples is introduced. We mathematically derive both the forward multi-slice scattering method as well as the gradient calculations in order to solve the inverse problem with optimization. As well, with the addition of regularization, the framework is robust against low dose tomography applications. Second, we demonstrate in simulation the validity of our method by varying different experimental parameters such as tilt angles, defocus values and dosage. Next, we test our ET framework experimentally on a multiple-scattering Montemorillonite clay, a 2D material submerged in aqueous solution and vitrified under cryogenic temperature. The results demonstrate the ability to observe the electric double layer (EDL) of this material for the first time. Last but not least, because modern electron detectors have large pixel counts and current imaging applications require large volume reconstructions, we developed a distributed computing method that can be directly applied to our framework for seeing multiple-scattering samples. Instead of solving for the 3D sample on a single computer node, we utilize tens or hundreds of nodes on a compute cluster simultaneously, with each node solving for part of the volume. As a result, both high resolution sample features and macroscopic sample topology can be visualized at the same time.},
keywords = {},
pubstate = {published},
tppubtype = {phdthesis}
}
Kristina Monakhova; Vi Tran; Grace Kuo; Laura Waller
Untrained networks for compressive lensless photography Journal Article
In: Opt. Express, vol. 29, no. 13, pp. 20913–20929, 2021.
Links | BibTeX | Tags: compressive imaging, compressive photography, high speed video, hyperspectral imaging, Hyperspectral imaging; Image quality; Imaging systems; Optical imaging; Phase imaging; Three dimensional imaging, learning-based
@article{Monakhova:21,
title = {Untrained networks for compressive lensless photography},
author = {Kristina Monakhova and Vi Tran and Grace Kuo and Laura Waller},
url = {http://www.opticsexpress.org/abstract.cfm?URI=oe-29-13-20913},
doi = {10.1364/OE.424075},
year = {2021},
date = {2021-06-01},
journal = {Opt. Express},
volume = {29},
number = {13},
pages = {20913--20929},
publisher = {OSA},
keywords = {compressive imaging, compressive photography, high speed video, hyperspectral imaging, Hyperspectral imaging; Image quality; Imaging systems; Optical imaging; Phase imaging; Three dimensional imaging, learning-based},
pubstate = {published},
tppubtype = {article}
}
Henry Pinkard; Hratch Baghdassarian; Adriana Mujal; Ed Roberts; Kenneth H Hu; Daniel Haim Friedman; Ivana Malenica; Taylor Shagam; Adam Fries; Kaitlin Corbin; others
Learned adaptive multiphoton illumination microscopy for large-scale immune response imaging Journal Article
In: Nature communications, vol. 12, no. 1, pp. 1–14, 2021.
Links | BibTeX | Tags: learning-based, microscopy, multiphoton
@article{pinkard2021learned,
title = {Learned adaptive multiphoton illumination microscopy for large-scale immune response imaging},
author = {Henry Pinkard and Hratch Baghdassarian and Adriana Mujal and Ed Roberts and Kenneth H Hu and Daniel Haim Friedman and Ivana Malenica and Taylor Shagam and Adam Fries and Kaitlin Corbin and others},
doi = {https://doi.org/10.1038/s41467-021-22246-5},
year = {2021},
date = {2021-01-01},
journal = {Nature communications},
volume = {12},
number = {1},
pages = {1--14},
publisher = {Nature Publishing Group},
keywords = {learning-based, microscopy, multiphoton},
pubstate = {published},
tppubtype = {article}
}
Henry Pinkard; Nico Stuurman; Ivan E Ivanov; Nicholas M Anthony; Wei Ouyang; Bin Li; Bin Yang; Mark A Tsuchida; Bryant Chhun; Grace Zhang; others
Pycro-Manager: open-source software for customized and reproducible microscope control Journal Article
In: Nature Methods, vol. 18, no. 3, pp. 226–228, 2021.
Links | BibTeX | Tags: microsopy, open-source software
@article{pinkard2021pycro,
title = {Pycro-Manager: open-source software for customized and reproducible microscope control},
author = {Henry Pinkard and Nico Stuurman and Ivan E Ivanov and Nicholas M Anthony and Wei Ouyang and Bin Li and Bin Yang and Mark A Tsuchida and Bryant Chhun and Grace Zhang and others},
doi = {https://doi.org/10.1038/s41592-021-01087-6},
year = {2021},
date = {2021-01-01},
journal = {Nature Methods},
volume = {18},
number = {3},
pages = {226--228},
publisher = {Nature Publishing Group},
keywords = {microsopy, open-source software},
pubstate = {published},
tppubtype = {article}
}
Stuart Sherwin; Isvar Cordova; Ryan Miyakawa; Markus Benk; Laura Waller; Andrew Neureuther; Patrick Naulleau
Picometer sensitivity metrology for EUV absorber phase Journal Article
In: Journal of Micro/Nanopatterning, Materials, and Metrology, vol. 20, no. 3, pp. 1 – 19, 2021.
Links | BibTeX | Tags: attenuated phase-shift mask, Carbon, Contamination, Etching, EUV absorber, extreme ultraviolet, mask three-dimensional, Metrology, Modulation, Multilayers, phase measurement, Phase shift keying, photomask contamination, Reflection, Reflectivity, Reflectometry
@article{10.1117/1.JMM.20.3.031011,
title = {Picometer sensitivity metrology for EUV absorber phase},
author = {Stuart Sherwin and Isvar Cordova and Ryan Miyakawa and Markus Benk and Laura Waller and Andrew Neureuther and Patrick Naulleau},
url = {https://doi.org/10.1117/1.JMM.20.3.031011},
doi = {10.1117/1.JMM.20.3.031011},
year = {2021},
date = {2021-01-01},
journal = {Journal of Micro/Nanopatterning, Materials, and Metrology},
volume = {20},
number = {3},
pages = {1 -- 19},
publisher = {SPIE},
keywords = {attenuated phase-shift mask, Carbon, Contamination, Etching, EUV absorber, extreme ultraviolet, mask three-dimensional, Metrology, Modulation, Multilayers, phase measurement, Phase shift keying, photomask contamination, Reflection, Reflectivity, Reflectometry},
pubstate = {published},
tppubtype = {article}
}
Stuart Sherwin; Isvar A Cordova; Ryan H Miyakawa; Markus P Benk; Laura Waller; Andrew R Neureuther; Patrick Naulleau
Picometer sensitivity metrology for EUV absorber phase Journal Article
In: Journal of Micro/Nanopatterning, Materials, and Metrology, vol. 20, no. 3, pp. 1 – 19, 2021.
Links | BibTeX | Tags: attenuated phase-shift mask, Carbon, Contamination, Etching, EUV absorber, extreme ultraviolet, mask three-dimensional, Metrology, Modulation, Multilayers, phase measurement, Phase shift keying, photomask contamination, Reflection, Reflectivity, Reflectometry
@article{10.1117/1.JMM.20.3.031011b,
title = {Picometer sensitivity metrology for EUV absorber phase},
author = {Stuart Sherwin and Isvar A Cordova and Ryan H Miyakawa and Markus P Benk and Laura Waller and Andrew R Neureuther and Patrick Naulleau},
url = {https://doi.org/10.1117/1.JMM.20.3.031011},
doi = {10.1117/1.JMM.20.3.031011},
year = {2021},
date = {2021-01-01},
journal = {Journal of Micro/Nanopatterning, Materials, and Metrology},
volume = {20},
number = {3},
pages = {1 -- 19},
publisher = {SPIE},
keywords = {attenuated phase-shift mask, Carbon, Contamination, Etching, EUV absorber, extreme ultraviolet, mask three-dimensional, Metrology, Modulation, Multilayers, phase measurement, Phase shift keying, photomask contamination, Reflection, Reflectivity, Reflectometry},
pubstate = {published},
tppubtype = {article}
}
Grace Kuo
Exploiting Randomness in Computational Cameras and Displays PhD Thesis
EECS Department, University of California, Berkeley, 2020.
Abstract | Links | BibTeX | Tags:
@phdthesis{Kuo:EECS-2020-218,
title = {Exploiting Randomness in Computational Cameras and Displays},
author = {Grace Kuo},
url = {http://www2.eecs.berkeley.edu/Pubs/TechRpts/2020/EECS-2020-218.html},
year = {2020},
date = {2020-12-01},
number = {UCB/EECS-2020-218},
school = {EECS Department, University of California, Berkeley},
abstract = {Despite its desirability, capturing and displaying higher dimensional content is still a novelty since image sensors and display panels are inherently 2D. A popular option is to use scanning mechanisms to sequentially capture 3D data or display content at a variety of depths. This approach is akin to directly measuring (or displaying) the content of interest, which has low computational cost but sacrifices temporal resolution and requires complex physical hardware with moving parts. The exacting specifications on the hardware make it challenging to miniaturize these optical systems for demanding applications such as neural imaging in animals or head-mounted augmented reality displays.
In this dissertation, I propose moving the burden of 3D capture from hardware into computation by replacing the physical scanning mechanisms with a simple static diffuser (a transparent optical element with pseudorandom thickness) and formulating image recovery as an optimization problem. First, I highlight the versatility of the diffuser by showing that it can replace a lens to create an easy-to-assemble, compact camera that is robust to missing pixels; although the raw data is not intelligible by a human, it contains information that we extract with optimization using an efficient physically-based model of the optics. Next, I show that the randomness of the diffuser makes the system well-suited for compressed sensing; we leverage this to recover 3D volumes from a single acquisition of raw data. Additionally, I extend our lensless 3D imaging system to fluorescence microscopy and introduce a new diffuser design with improved noise performance. Finally, I show how incorporating the diffuser in a 3D holographic display expands the field-of-view, and I demonstrate state-of-the-art performance by using perceptually inspired loss functions when optimizing the display panel pattern. These results show how randomness in the optical system in conjunction with optimization-based algorithms can both improve the physical form factor and expand the capabilities of cameras, microscopes, and displays.},
keywords = {},
pubstate = {published},
tppubtype = {phdthesis}
}
In this dissertation, I propose moving the burden of 3D capture from hardware into computation by replacing the physical scanning mechanisms with a simple static diffuser (a transparent optical element with pseudorandom thickness) and formulating image recovery as an optimization problem. First, I highlight the versatility of the diffuser by showing that it can replace a lens to create an easy-to-assemble, compact camera that is robust to missing pixels; although the raw data is not intelligible by a human, it contains information that we extract with optimization using an efficient physically-based model of the optics. Next, I show that the randomness of the diffuser makes the system well-suited for compressed sensing; we leverage this to recover 3D volumes from a single acquisition of raw data. Additionally, I extend our lensless 3D imaging system to fluorescence microscopy and introduce a new diffuser design with improved noise performance. Finally, I show how incorporating the diffuser in a 3D holographic display expands the field-of-view, and I demonstrate state-of-the-art performance by using perceptually inspired loss functions when optimizing the display panel pattern. These results show how randomness in the optical system in conjunction with optimization-based algorithms can both improve the physical form factor and expand the capabilities of cameras, microscopes, and displays.