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Related papers: Near-field speckle-scanning-based X-ray tomography

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Spectral computed tomography (CT) has recently emerged as an advanced version of medical CT and significantly improves conventional (single-energy) CT. Spectral CT has two main forms: dual-energy computed tomography (DECT) and…

X-ray computed tomography (CT) is one of the most common imaging techniques used to diagnose various diseases in the medical field. Its high contrast sensitivity and spatial resolution allow the physician to observe details of body parts…

Image and Video Processing · Electrical Eng. & Systems 2023-08-03 Daeun Kyung , Kyungmin Jo , Jaegul Choo , Joonseok Lee , Edward Choi

As computational tools for X-ray computed tomography (CT) become more quantitatively accurate, knowledge of the source-detector spectral response is critical for quantitative system-independent reconstruction and material characterization…

Image and Video Processing · Electrical Eng. & Systems 2023-02-28 Wenrui Li , Venkatesh Sridhar , K. Aditya Mohan , Saransh Singh , Jean-Baptiste Forien , Xin Liu , Gregery T. Buzzard , Charles A. Bouman

X-ray energy spectrum plays an essential role in imaging and related tasks. Due to the high photon flux of clinical CT scanners, most of the spectrum estimation methods are indirect and are usually suffered from various limitations. The…

Medical Physics · Physics 2016-04-19 Wei Zhao , Qiude Zhang , Tianye Niu

X-ray 3D tomography is So far limited to micron resolution because of the large focusing spot of the focused electron beam on the metal target. Here, we proposed a nanofocous X-ray 3D tomography system based on focused electrons from…

Instrumentation and Detectors · Physics 2018-03-14 Gholamreza Shayeganrad

Speckle imaging is a well known method to achieve diffraction-limited (DL) imaging from ground-based telescopes. The traditional observing method for speckle has been to observe a single, unresolved, source per telescope pointing over a…

Instrumentation and Methods for Astrophysics · Physics 2018-06-04 James W. Davidson , Elliott P. Horch , Steven R. Majewski

Sonography techniques use multiple transducer elements for tissue visualization. Signals detected at each element are sampled prior to digital beamforming. The sampling rates required to perform high resolution digital beamforming are…

Information Theory · Computer Science 2013-07-25 Tanya Chernyakova , Yonina C. Eldar

X-ray parametric down-conversion is a fundamental nonlinear effect that promises a wide range of possible applications. Nevertheless, it has been scarcely investigated and unequivocal evidence of the effect is still missing for certain…

This article begins with the discussions on the formation of speckles in the case of non-coherent quasi monochromatic source and of ways to detect them. Prior to this, a brief introduction on the behavior of the atmosphere and its effect on…

Astrophysics · Physics 2007-05-23 Swapan K. Saha

The spherical nature of the wavefronts exhibited in the near-field of antenna arrays enables advanced beamforming capabilities, such as beampointing and beamnulling. In this paper, we exploit these properties to design a near-field beam…

Signal Processing · Electrical Eng. & Systems 2026-02-16 Laurence Defraigne , Gilles Monnoyer , Jérôme Louveaux , Luc Vandendorpe

Circular aperture probes have been successfully used for high-resolution near-field microwave imaging. It has been established that circular aperture probes could conceivably provide higher image fidelity compared to rectangular aperture…

Systems and Control · Electrical Eng. & Systems 2022-12-13 Zubair Akhter , MS Rahman , M Aboukhousa

We propose X-NeRF, a novel method to learn a Cross-Spectral scene representation given images captured from cameras with different light spectrum sensitivity, based on the Neural Radiance Fields formulation. X-NeRF optimizes camera poses…

Computer Vision and Pattern Recognition · Computer Science 2022-09-02 Matteo Poggi , Pierluigi Zama Ramirez , Fabio Tosi , Samuele Salti , Stefano Mattoccia , Luigi Di Stefano

X-ray dark-field imaging visualises scattering from sample microstructure, and has found application in medical and security contexts. While most X-ray dark-field imaging techniques rely on masks, gratings, or crystals, recent work on the…

Elastic light scattering has been extensively used to study samples showing a non uniform refraction index on lengthscales from a fraction of a micrometer to a fraction of a millimeter. Typically, a wide laser beam is sent through the…

Optics · Physics 2009-07-21 Doriano Brogioli

X-ray photoelectron spectroscopy (XPS) is a widely used technique for chemical analysis of solid surfaces, sensitive to the chemical environments of atoms via core-level binding energy shifts. While modern instruments allow experimental…

Materials Science · Physics 2026-05-12 Jan Čechal

M\"ossbauer nuclei feature exceptionally narrow resonances at hard x-ray energies, which render them ideal probes for structure and dynamics in condensed-matter systems, and a promising platform for x-ray quantum optics and fundamental…

Quantum Physics · Physics 2020-07-01 Benedikt Herkommer , Jörg Evers

This work is concerned with applying iterative image reconstruction, based on constrained total-variation minimization, to low-intensity X-ray CT systems that have a high sampling rate. Such systems pose a challenge for iterative image…

Medical Physics · Physics 2016-11-17 Emil Y. Sidky , Rick Chartrand , Yuval Duchin , Christer Ullberg , Xiaochuan Pan

Paradoxically, imaging with resolution much below the wavelength $\lambda$ - now common place in the visible spectrum - remains challenging at lower frequencies, where arguably it is needed most due to the large wavelengths used. Techniques…

Optics · Physics 2023-12-12 Alessandro Tuniz , Boris T. Kuhlmey

Spectral imaging is a fundamental diagnostic technique with widespread application. Conventional spectral imaging approaches have intrinsic limitations on spatial and spectral resolutions due to the physical components they rely on. To…

Image and Video Processing · Electrical Eng. & Systems 2021-06-07 Figen S. Oktem , Oğuzhan Fatih Kar , Can Deniz Bezek , Farzad Kamalabadi

X-ray imaging, traditionally relying on attenuation contrast, struggles to differentiate materials with similar attenuation coefficients like soft tissues. X-ray phase contrast imaging (XPCI) and dark-field (DF) imaging provide enhanced…

Medical Physics · Physics 2025-06-05 Jingcheng Yuan , Mini Das