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Fourier ptychography (FP) is a powerful light-based synthetic aperture imaging technique that allows one to reconstruct a high-resolution, wide field-of-view image by computationally integrating a diverse collection of low-resolution,…

Image and Video Processing · Electrical Eng. & Systems 2025-07-21 Matthew A. Chan , Casey J. Pellizzari , Christopher A. Metzler

Fourier ptychography microscopy (FPM), sharing its roots with synthetic aperture technique and phase retrieval method, is a recently developed computational microscopic super-resolution technique. By turning on the light-emitting diode…

Optics · Physics 2021-05-07 G. Zhou , S. Zhang , C. Zheng , T. Li , Y. Hu , Q. Hao

Assume you encounter an inverse problem that shall be solved for a large number of data, but no ground-truth data is available. To emulate this encounter, in this study, we assume it is unknown how to solve the imaging problem of Computed…

The use of Fourier methods in wave-front reconstruction can significantly reduce the computation time for large telescopes with a high number of degrees of freedom. However, Fourier algorithms for discrete data require a rectangular data…

Instrumentation and Methods for Astrophysics · Physics 2017-06-07 Charlotte Z. Bond , Carlos M. Correia , Jean-François Sauvage , Benoit Neichel , Thierry Fusco

We present an extension of the Coronal Reconstruction Onto B-Aligned Regions (CROBAR) method to Linear Force Free Field (LFFF) extrapolations, and apply it to the reconstruction of a set of AIA, MDI, and STEREO EUVI data. The results…

Solar and Stellar Astrophysics · Physics 2026-01-29 Joseph Plowman , Daniel B. Seaton , Amir Caspi , J. Marcus Hughes , Matthew J. West

The large availability and rich spectral coverage of today's observational data of the solar corona, and the high spatial and temporal resolution of many instruments, has enabled the evolution of three-dimensional (3D) physical models to a…

Solar and Stellar Astrophysics · Physics 2015-03-10 Alberto Marcos Vásquez

The quality of images of the Sun obtained from the ground are severely limited by the perturbing effect of the turbulent Earth's atmosphere. The post-facto correction of the images to compensate for the presence of the atmosphere require…

Solar and Stellar Astrophysics · Physics 2018-12-05 A. Asensio Ramos , J. de la Cruz Rodriguez , A. Pastor Yabar

We report on the initial results obtained with an image convolution/deconvolution computer code that we developed and used to study the image formation capabilities of the solar gravitational lens (SGL). Although the SGL of a spherical Sun…

General Relativity and Quantum Cosmology · Physics 2021-06-15 Viktor T. Toth , Slava G. Turyshev

Computed Tomography (CT) reconstruction of objects with cylindrical symmetry can be performed with a single projection. When the measured rays are parallel, and the axis of symmetry is perpendicular to the optical axis, the data can be…

Medical Physics · Physics 2024-10-15 Kyle M. Champley , Ibrahim Oksuz , Matthew G. Bisbee , Joseph W. Tringe , Brian Maddox

Deep sub-diffraction exoplanet discovery currently lies beyond the reach of state-of-the-art direct imaging coronagraphs, which typically have an inner working angle larger than the diffraction scale. We present an experimental…

Instrumentation and Methods for Astrophysics · Physics 2025-05-06 Nico Deshler , Itay Ozer , Amit Ashok , Saikat Guha

The inference of the magnetic field vector from spectropolarimetric observations is crucial for understanding the physical processes governing the solar corona. We investigate which information on the magnetic fields of coronal bright…

Solar and Stellar Astrophysics · Physics 2025-08-27 Ernest Alsina Ballester , Daniel Nóbrega-Siverio , Fernando Moreno-Insertis , Supriya Hebbur Dayananda

The image reconstruction of chromophore concentrations using Diffuse Optical Tomography (DOT) data can be described mathematically as an ill-posed inverse problem. Recent work has shown that the use of hyperspectral DOT data, as opposed to…

Numerical Analysis · Mathematics 2014-10-16 Arvind K. Saibaba , Misha Kilmer , Eric Miller , Sergio Fantini

We consider both facial reduction, \FRp, and symmetry reduction, \SRp, techniques for semidefinite programming, \SDPp. We show that the two together fit surprisingly well in an alternating direction method of multipliers, \ADMMp, approach.…

Optimization and Control · Mathematics 2022-02-04 Hao Hu , Renata Sotirov , Henry Wolkowicz

We present preliminary reconstructions of the EUV from 26 to 34\,nm from February 1997 to May 2005, covering most of solar cycle 23. The reconstruction is based on synthetic EUV spectra calculated with the spectral synthesis code Solar…

Solar and Stellar Astrophysics · Physics 2015-06-05 Margit Haberreiter

We introduce a new CT image reconstruction algorithm that is less affected by various artifacts. The new reconstruction algorithm is a method of minimizing the difference between synchrotron X-ray tomography data and sinograms generated…

Medical Physics · Physics 2021-11-22 Byung Chun Kim , Hyunju Lee , Kyungtaek Jun

Point-spread function (PSF) estimation in spatially undersampled images is challenging because large pixels average fine-scale spatial information. This is problematic when fine-resolution details are necessary, as in optimal photometry…

Instrumentation and Methods for Astrophysics · Physics 2021-02-03 Teresa Symons , Michael Zemcov , James Bock , Yun-Ting Cheng , Brendan Crill , Christopher Hirata , Stephanie Venuto

Fluorescence molecular tomography (FMT) has potential of providing high contrast images for breast tumor detection. Computational phantom provides a convenient way to a wide variety of fluorophore distribution configurations in patients and…

Medical Physics · Physics 2018-04-02 Yansong Zhu , Abhinav K. Jha , Arman Rahmim

The Atmospheric Imaging Assembly in the Solar Dynamics Observatory provides full Sun images every 1 seconds in each of 7 Extreme Ultraviolet passbands. However, for a significant amount of these images, saturation affects their most intense…

Instrumentation and Methods for Astrophysics · Physics 2015-09-02 Gabriele Torre , Richard A Schwartz , Federico Benvenuto , Anna Maria Massone , Michele Piana

We present a fast iterative FFT-based reconstruction algorithm that allows for non- parallel redshift-space distortions (RSD). We test our algorithm on both N-body dark matter simulations and mock distributions of galaxies designed to…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-17 Angela Burden , Will J. Percival , Cullan Howlett

Speckle Imaging based on triple correlation is a very efficient image reconstruction technique which is used to retrieve Fourier phase information of the object in presence of atmospheric turbulence. We have developed both Direct Bispectrum…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha
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