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In High Contrast Imaging, a large instrumental, technological and algorithmic effort is made to reduce residual speckle noise and improve the detection capabilities. In this work, we explore the potential of using a precise physical…

Instrumentation and Methods for Astrophysics · Physics 2024-02-13 Dotan Gazith , Barak Zackay

Estimating uncertainty in image-to-image networks is an important task, particularly as such networks are being increasingly deployed in the biological and medical imaging realms. In this paper, we introduce a new approach to this problem…

Computer Vision and Pattern Recognition · Computer Science 2022-11-29 Gilad Kutiel , Regev Cohen , Michael Elad , Daniel Freedman

We develop a means for speckle-based phase imaging of the projected thickness of a single-material object, under the assumption of illumination by spatially random time-independent x-ray speckles. These speckles are generated by passing x…

We demonstrate two new approaches that have been developed to aid the production of future hard X-ray catalogs, and specifically to reduce the reliance on human intervention during the detection of faint excesses in maps that also contain…

High Energy Astrophysical Phenomena · Physics 2022-01-19 V. A. Lepingwell , A. J. Bird , S. R. Gunn

This paper is concerned with the inverse scattering problem by an unbounded rough surface. A direct imaging method is proposed to reconstruct the rough surface from the scattered near-field Cauchy data generating by point sources and…

Numerical Analysis · Mathematics 2018-05-01 Xiaoli Liu , Bo Zhang , Haiwen Zhang

X-ray dark-field imaging creates a representation of the sample where contrast is generated by subresolution features within the volume under inspection. These are detected by a local measurement of the radiation field's angular…

Classical methods for X-ray computed tomography are based on the assumption that the X-ray source intensity is known, but in practice, the intensity is measured and hence uncertain. Under normal operating conditions, when the exposure time…

Numerical Analysis · Mathematics 2017-07-17 Hari Om Aggrawal , Martin Skovgaard Andersen , Sean Rose , Emil Y. Sidky

Recent developments in x-ray science provide methods to probe deeply embedded mesoscale grain structures and spatially resolve them using dark field x-ray microscopy (DFXM). Extending this technique to investigate weak diffraction signals…

For nonlinear multispectral computed tomography (CT), accurate and fast image reconstruction is challenging when the scanning geometries under different X-ray energy spectra are inconsistent or mismatched. Motivated by this, we propose an…

Numerical Analysis · Mathematics 2025-07-28 Yu Gao , Chong Chen

X-ray fluorescence holography (XFH) is a method for obtaining diffraction-limited images of the local atomic structure around a given type of emitter. The reconstructed wave-field represents a distorted image of the scatterer electron…

Condensed Matter · Physics 2009-09-29 S. Marchesini , C. S. Fadley , F. J. Garcia de Abajo

We present the results of simulations of shadows cast by a zone plate telescope which may have one to four pairs of zone plates. From the shadows we reconstruct the images under various circumstances. We discuss physical basis of the…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 S. Palit , Sandip K. Chakrabarti , D. Debnath , A. R. Rao , A. Nandi , Vipin K. Yadav , V. Girish

Three-dimensional segmentation in magnetic resonance images (MRI), which reflects the true shape of the objects, is challenging since high-resolution isotropic MRIs are rare and typical MRIs are anisotropic, with the out-of-plane dimension…

Image and Video Processing · Electrical Eng. & Systems 2023-03-15 Hanxue Gu , Hongyu He , Roy Colglazier , Jordan Axelrod , Robert French , Maciej A Mazurowski

Super-resolution imaging has revolutionized the study of systems ranging from molecular structures to distant galaxies. However, existing super-resolution methods require extensive calibration and retraining for each imaging setup, limiting…

Optics · Physics 2026-03-24 Dominik Vašinka , Filip Juráň , Jaromír Běhal , Miroslav Ježek

We report the experimental super-resolution of pairs of point-like fluorescent sources using a modified image inversion interferometer microscope. The technique is inspired by recent developments in the application of quantum parameter…

Adaptive finite elements are the method of choice for accurate simulations of optical components. However as shown recently by Bienstman et al. many finite element mode solvers fail to compute the propagation constant's imaginary part of a…

Optics · Physics 2009-05-28 L. Zschiedrich , S. Burger , J. Pomplun , F. Schmidt

Traditional glass-based optics are typically optimized for narrow spectral bands, such as the visible (400-700nm) or shortwave infrared (1000-1800nm). While the emergence of VIS-SWIR sensors (400-1700nm) offers transformative potential,…

Image and Video Processing · Electrical Eng. & Systems 2026-05-04 Vishwanath Saragadam , Niki Nezakati , Amit Roy-Chowdhury , Vivek Boominathan

We describe an X-ray source detection method entirely based on the maximum likelihood analysis, in application to observations with the ART-XC telescope onboard the Spectrum Roentgen Gamma observatory. The method optimally combines the data…

High Energy Astrophysical Phenomena · Physics 2024-04-03 A. Semena , A. Vikhlinin , I. Mereminskiy , A. Lutovinov , A. Tkachenko , I. Lapshov , R. Burenin

We present a concept of the X-ray imaging system with high angular-resolution and moderate sensitivity. In this concept, a two-dimensional detector, i.e., imager, is put at a slightly out-of-focused position of the focusing mirror, rather…

Instrumentation and Methods for Astrophysics · Physics 2019-10-23 Yoshitomo Maeda , Ryo Iizuka , Takayuki Hayashi , Toshiki Sato , Nozomi Nakaniwa , Mai Takeo , Hitomi Suzuki , Manabu Ishida , Shiro Ikeda , Mikio Morii

The aim of this research is to reconstruct the 3D X-ray refractive index gradient maps by the proposed vector Radon transform and its inverse, assuming that the small-angle deviation condition is met. Theoretical analyses show that the…

Medical Physics · Physics 2023-09-20 Keliang Liao , Qili He , Panyun Li , Liang Luo , Peiping Zhu

We present a superpixel method for full spatial phase and amplitude control of a light beam using a digital micromirror device (DMD) combined with a spatial filter. We combine square regions of nearby micromirrors into superpixels by low…

Optics · Physics 2015-06-19 Sebastianus A. Goorden , Jacopo Bertolotti , Allard P. Mosk