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Related papers: Single-Image Geometric-Flow X-Ray Speckle Tracking

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By utilizing the frequency anticorrelation of two-photon states produced via spontaneous parametric down conversion (SPDC), the working principle of a novel remote spectrometer is demonstrated. With the help of a local scanning…

Quantum Physics · Physics 2016-09-08 Giuliano Scarcelli , Alejandra Valencia , Samuel Gompers , Yanhua Shih

Propagation-based X-ray phase contrast enables nanoscale imaging of biological tissue by probing not only the attenuation, but also the real part of the refractive index of the sample. Since only intensities of diffracted waves can be…

Numerical Analysis · Mathematics 2017-09-11 Simon Maretzke , Thorsten Hohage

We demonstrate experimentally and theoretically that a coherent image of a pure phase object may be obtained by use of a spatially incoherent illumination beam. This is accomplished by employing a two-beam source of entangled photons…

A method to calculate particle fluxes applicable in most of the spectroscopy techniques is described. Flux intensities of backscattered or absorbed electrons and emitted photons are calculated using a method of convergence to solve the…

Materials Science · Physics 2015-06-05 C. Figueroa , N. Nieva , H. Brizuela , S. P. Heluani

A novel scheme for Zernike-type hard X-ray phase-contrast imaging is proposed. The scheme relies on X-ray dynamical diffraction in a two-block crystal system with parallel crystal plates of equal thickness. A phase shifter providing a…

Optics · Physics 2026-02-27 Levon Haroutunyan

We extend our previously proposed image reconstruction method, which allows confocal microscopes to capture periodically moving objects at frequencies beyond their frame rates, to three-dimensional and two-dimensional wide-field imaging.…

Optics · Physics 2026-03-03 Kanta Adachi , Soyoka Hemmi , Nobutomo Nakamura

Object pose tracking is one of the pivotal technologies in multimedia, attracting ever-growing attention in recent years. Existing methods employing traditional cameras encounter numerous challenges such as motion blur, sensor noise,…

Computer Vision and Pattern Recognition · Computer Science 2025-12-25 Zibin Liu , Banglei Guan , Yang Shang , Shunkun Liang , Zhenbao Yu , Qifeng Yu

Using higher-order coherence of thermal light sources, the resolution power of standard x-ray imaging techniques can be enhanced. In this work, we applied the higher-order measurement to far-field x-ray diffraction and near-field phase…

X-ray ptychography is a cutting edge imaging technique providing ultra-high spatial resolutions. In ptychography, phase retrieval, i.e., the recovery of a complex valued signal from intensity-only measurements, is enabled by exploiting a…

Image and Video Processing · Electrical Eng. & Systems 2022-09-14 Felix Wittwer , Peter Modregger

In support of art investigation, we propose a new source separation method that unmixes a single X-ray scan acquired from double-sided paintings. In this problem, the X-ray signals to be separated have similar morphological characteristics,…

Computer Vision and Pattern Recognition · Computer Science 2016-11-15 Nikos Deligiannis , Joao F. C. Mota , Bruno Cornelis , Miguel R. D. Rodrigues , Ingrid Daubechies

The point spread function (PSF) serves as a fundamental descriptor linking the real-world scene to the captured signal, manifesting as camera blur. Accurate PSF estimation is crucial for both optical characterization and computational…

Computer Vision and Pattern Recognition · Computer Science 2026-01-13 Jiajian He , Enjie Hu , Shiqi Chen , Tianchen Qiu , Huajun Feng , Zhihai Xu , Yueting Chen

We consider a variational method to solve the optical flow problem with varying illumination. We apply an adaptive control of the regularization parameter which allows us to preserve the edges and fine features of the computed flow. To…

Computer Vision and Pattern Recognition · Computer Science 2015-08-13 Diane Gilliocq-Hirtz , Zakaria Belhachmi

In this paper, we develop a novel phase retrieval approach to reconstruct x-ray differential phase shift induced by an object. A primary advantage of our approach is a higher-order accuracy over that with the conventional linear…

Medical Physics · Physics 2010-03-18 Wenxiang Cong , Ge Wang

Following the tracks of Malbet, Yu, & Shao (1995} on dark hole algorithms, we present analytical methods to measure and correct the speckle noise behind an ideal coronagraph. We show that, in a low aberration regime, wavefront sensing can…

Astrophysics · Physics 2009-11-11 Pascal Borde , Wesley Traub

Achieving high spatial resolution is the goal of many imaging systems. Designing a high-resolution lens with diffraction-limited performance over a large field of view remains a difficult task in imaging system design. On the other hand,…

One of the most powerful approaches to imaging at the nanometer or subnanometer length scale is coherent diffraction imaging using X-ray sources. For amorphous (non-crystalline) samples, the raw data can be interpreted as the modulus of the…

Numerical Analysis · Mathematics 2020-04-02 Alexander Barnett , Charles L. Epstein , Leslie Greengard , Jeremy Magland

In this paper we present a decomposition algorithm for computation of the spatial-temporal optical flow of a dynamic image sequence. We consider several applications, such as the extraction of temporal motion features and motion detection…

Computer Vision and Pattern Recognition · Computer Science 2017-01-31 Aniello Raffale Patrone , Otmar Scherzer

Tracing the motion of electrons has enormous relevance to understanding ubiquitous phenomena in ultrafast science, such as the dynamical evolution of the electron density during complex chemical and biological processes. Scattering of…

Atomic Physics · Physics 2013-03-28 Gopal Dixit , Jan Malte Slowik , Robin Santra

We present a numerical method for studying the normal modes of accretion flows around black holes. In this first paper, we focus on two-dimensional, viscous, hydrodynamic disks, for which the linear modes have been calculated analytically…

Astrophysics · Physics 2009-11-10 Chi-kwan Chan , Dimitrios Psaltis , Feryal Ozel

We present a simple and effective method to eliminate system aberrations and speckle noise in quantitative phase imaging. Using spiral integration, complete information about system aberration is calculated from three laterally shifted…

Biological Physics · Physics 2018-02-14 Inhyeok Choi , Kyeoreh Lee , YongKeun Park