English
Related papers

Related papers: Aliasing-reduced Fresnel diffraction with scale an…

200 papers

One-dimensional optical waveguiding is revisited using the electromagnetic deduction of Fresnel formulas relating the incident, reflected, and transmitted waves on the abrupt interface between two different optical media. Throughout the…

Radio interferometers targeting the 21cm brightness temperature fluctuations at high redshift are subject to systematic effects that operate over a range of different timescales. These can be isolated by designing appropriate Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-09 Hugh Garsden , Philip Bull , Mike Wilensky , Zuhra Abdurashidova , Tyrone Adams , James E. Aguirre , Paul Alexander , Zaki S. Ali , Rushelle Baartman , Yanga Balfour , Adam P. Beardsley , Lindsay M. Berkhout , Gianni Bernardi , Tashalee S. Billings , Judd D. Bowman , Richard F. Bradley , Jacob Burba , Steven Carey , Chris L. Carilli , Kai-Feng Chen , Carina Cheng , Samir Choudhuri , David R. DeBoer , Eloy de Lera Acedo , Matt Dexter , Joshua S. Dillon , Scott Dynes , Nico Eksteen , John Ely , Aaron Ewall-Wice , Nicolas Fagnoni , Randall Fritz , Steven R. Furlanetto , Kingsley Gale-Sides , Bharat Kumar Gehlot , Abhik Ghosh , Brian Glendenning , Adelie Gorce , Deepthi Gorthi , Bradley Greig , Jasper Grobbelaar , Ziyaad Halday , Bryna J. Hazelton , Jacqueline N. Hewitt , Jack Hickish , Tian Huang , Daniel C. Jacobs , Alec Josaitis , Austin Julius , MacCalvin Kariseb , Nicholas S. Kern , Joshua Kerrigan , Honggeun Kim , Piyanat Kittiwisit , Saul A. Kohn , Matthew Kolopanis , Adam Lanman , Paul La Plante , Adrian Liu , Anita Loots , Yin-Zhe Ma , David H. E. MacMahon , Lourence Malan , Cresshim Malgas , Keith Malgas , Bradley Marero , Zachary E. Martinot , Andrei Mesinger , Mathakane Molewa , Miguel F. Morales , Tshegofalang Mosiane , Steven G. Murray , Abraham R. Neben , Bojan Nikolic , Chuneeta Devi Nunhokee , Hans Nuwegeld , Aaron R. Parsons , Robert Pascua , Nipanjana Patra , Samantha Pieterse , Yuxiang Qin , Eleanor Rath , Nima Razavi-Ghods , Daniel Riley , James Robnett , Kathryn Rosie , Mario G. Santos , Peter Sims , Saurabh Singh , Dara Storer , Hilton Swarts , Jianrong Tan , Nithyanandan Thyagarajan , Pieter van Wyngaarden , Peter K. G. Williams , Zhilei Xu , Haoxuan Zheng

The fractional Fourier transform (FrFT), which is a generalization of the Fourier transform, has become the focus of many research papers in recent years because of its applications in electrical engineering and optics. In this paper, we…

Functional Analysis · Mathematics 2020-08-21 Owais Ahmad , Neyaz A. Sheikh , Firdous A. Shah

The Fraunhofer diffraction of quantum particles from materials with sharp electron-density edges or symmetric bond structures is ubiquitous. In contrast, diffraction from atoms with characteristic asymptotically-diffused electron…

The Fourier-Transform ghost imaging of both amplitude-only and pure-phase objects was experimentally observed with classical incoherent light at Fresnel distance by a new lensless scheme. The experimental results are in good agreement with…

Quantum Physics · Physics 2015-06-26 Minghui Zhang , Qing Wei , Xia Shen , Yongfeng Liu , Honglin Liu , Jing Cheng , Shensheng Han

This paper concerns diffraction-tomographic reconstruction of an object characterized by its scattering potential. We establish a rigorous generalization of the Fourier diffraction theorem in arbitrary dimension, giving a precise relation…

Numerical Analysis · Mathematics 2026-03-30 Clemens Kirisits , Michael Quellmalz , Eric Setterqvist

Astrophysical lensing has typically been studied in two regimes: diffractive optics and refractive optics. Diffractive optics is characterized by a perturbative expansion of the Kirchhoff-Fresnel diffraction integral, while refractive…

High Energy Astrophysical Phenomena · Physics 2023-08-09 Dylan L. Jow , Ue-Li Pen , Job Feldbrugge

In this article, we study the properties of the nonlinear Fourier spectrum in order to gain better control of the temporal support of the signals synthesized using the inverse nonlinear Fourier transform (NFT). In particular, we provide…

Computational Physics · Physics 2018-09-17 Vishal Vaibhav

We propose a numerical interferometry method for identification of optical multiply-scattering systems when only intensity can be measured. Our method simplifies the calibration of optical transmission matrices from a quadratic to a linear…

Signal Processing · Electrical Eng. & Systems 2020-02-17 Sidharth Gupta , Rémi Gribonval , Laurent Daudet , Ivan Dokmanić

Correlation filters (CFs) are a class of classifiers that are attractive for object localization and tracking applications. Traditionally, CFs have been designed in the frequency domain using the discrete Fourier transform (DFT), where…

Computer Vision and Pattern Recognition · Computer Science 2016-11-18 Joseph A. Fernandez , Vishnu Naresh Boddeti , Andres Rodriguez , B. V. K. Vijaya Kumar

I derive in this paper theoretical expressions for biases on fringe contrast and fringe visibility phase for optical interferometers whose polarizing properties can be described by beam rotation, retardance, and diattenuation. The nature of…

Instrumentation and Methods for Astrophysics · Physics 2025-04-07 Guy Perrin

We present a method for measuring the transmission loss of an optical fiber using simplified optical correlation-domain reflectometry. By intentionally lowering the spatial resolution of the system, we observe the Rayleigh scattered signal…

Diffractive X-ray telescopes using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution several orders of magnitude better than available in…

Instrumentation and Methods for Astrophysics · Physics 2010-09-14 Gerald K. Skinner

The design of starshades, i.e. external occulters for stellar coronography, relies on the fast and precise computation of their associated diffraction patterns of incoming plane waves in the telescope aperture plane. We present here a…

Instrumentation and Methods for Astrophysics · Physics 2024-11-06 Simon Prunet , Claude Aime , André Ferrari , Céline Theys

Diffraction of coherent x-ray beams is treated through the Fractionnal Fourier transform. The transformation allow us to deal with coherent diffraction experiments from the Fresnel to the Fraunhofer regime. The analogy with the…

Other Condensed Matter · Physics 2025-01-08 David Le Bolloc'h , Jean-Francois Sadoc

We experimentally demonstrate that the transmission though rolled-up metal/semiconductor hyperlenses can be enhanced at desired frequencies utilizing Fabry-P\'erot resonances. By means of finite difference time domain simulations we prove…

The reported results for ultrasonic wave attenuation constant ({\alpha}) in pure water show noticeable inconsistency in magnitude. A "Propagating-Wave" model analysis of the most popular pulse-echo technique indicates that this is a…

Other Condensed Matter · Physics 2018-01-18 Barnana Pal

Features based on sparse representation, especially using the synthesis dictionary model, have been heavily exploited in signal processing and computer vision. However, synthesis dictionary learning typically involves NP-hard sparse coding…

Machine Learning · Computer Science 2017-10-17 Bihan Wen , Saiprasad Ravishankar , Yoram Bresler

The intersection of Astronomy and AI encounters significant challenges related to issues such as noisy backgrounds, lower resolution (LR), and the intricate process of filtering and archiving images from advanced telescopes like the James…

Computer Vision and Pattern Recognition · Computer Science 2024-05-24 Mohammed Talha Alam , Raza Imam , Mohsen Guizani , Fakhri Karray

In this paper, we focus on Fourier analysis and holographic transforms for signal representation. For instance, in the case of image processing, the holographic representation has the property that an arbitrary portion of the transformed…

Computer Vision and Pattern Recognition · Computer Science 2011-11-09 G. A. Giraldi , B. F. Moutinho , D. M. L. de Carvalho , J. C. de Oliveira