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Related papers: Speckle Imaging: a boon for astronomical observati…

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The simple physics of microlensing provides a well-understood tool with which to probe the atmospheres of distant stars in the Galaxy and Local Group with high magnification and resolution. Recent results in measuring stellar surface…

Astrophysics · Physics 2007-05-23 Penny D. Sackett

One of the well-known problems of producing instruments for Extremely Large Telescopes is that their size (and hence cost) scales rapidly with telescope aperture. To try to break this relation alternative new technologies have been…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 R. J. Harris , J. R. Allington-Smith

We briefly present the history of technical solutions aimed at improving the efficiency of spectroscopy on small- and moderate-diameter telescopes. We assess the current state of spectroscopy techniques and some of the perspectives.

Solar and Stellar Astrophysics · Physics 2021-05-27 V. E. Panchuk , V. G. Klochkova , E. V. Emelianov

Astronomical objects frequently exhibit structure over a wide range of scales whereas many telescopes, especially interferometer arrays, only sample a limited range of spatial scales. In order to properly image these objects, images from a…

Instrumentation and Methods for Astrophysics · Physics 2017-07-26 W. D. Cotton

In many practical applications of long-range imaging such as biometrics and surveillance, thermal imagining modalities are often used to capture images in low-light and nighttime conditions. However, such imaging systems often suffer from…

Computer Vision and Pattern Recognition · Computer Science 2022-04-08 Kangfu Mei , Yiqun Mei , Vishal M. Patel

We present a graphical interface designed to demonstrate the techniques of radio interferometry used by telescopes like ALMA, e-Merlin, the JVLA and SKA, in a manner accessible to the general public. Interferometry is an observational tech-…

Instrumentation and Methods for Astrophysics · Physics 2012-11-02 Adam Avison , Samuel J George

Optical interferometry provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Through direct observation of rotationally distorted photospheres at sub-milliarcsecond scales, we are now able to…

Solar and Stellar Astrophysics · Physics 2012-04-13 Gerard T. van Belle

Extra-solar planets have not been imaged directly with existing ground or space telescopes because they are too faint to be seen against the halo of the nearby bright star. Most techniques being explored to suppress the halo are achromatic,…

Astrophysics · Physics 2009-11-10 Johanan L. Codona , Roger Angel

This is the third article in a series of three dealing with the exploitation of speckle for imaging purposes. In complex media, a fundamental limit is the multiple scattering phenomenon that completely blurs the imaging process in depth.…

Applied Physics · Physics 2026-02-06 Elsa Giraudat , Flavien Bureau , William Lambert , Mathias Fink , Alexandre Aubry

Spectrograph is an optical device that is used to disperse photons of different energies $E$ into distinct directions and space locations, and to take a snapshot of the whole spectrum of photon energies with a spatially sensitive photon…

Optics · Physics 2015-06-03 Yuri Shvyd'ko

In this paper we analyze an imaging technique based on intensity speckle correlations over incident field position proposed in [J. A. Newmann and K. J. Webb, Phys. Rev. Lett. 113, 263903 (2014)]. Its purpose is to reconstruct a field…

Analysis of PDEs · Mathematics 2018-08-01 Josselin Garnier , Knut Solna

Imaging through scattering media is a longstanding issue in a wide range of applications, including biomedicine, security, and astronomy. Speckle-correlation imaging is promising for non-invasively seeing through scattering media by…

Optics · Physics 2022-10-13 Yuto Endo , Jun Tanida , Makoto Naruse , Ryoichi Horisaki

Imaging with optical resolution through highly scattering media is a long sought-after goal with important applications in deep tissue imaging. Although being the focus of numerous works, this goal was considered impractical until recently.…

Optics · Physics 2012-02-10 Ori Katz , Eran Small , Yaron Silberberg

Speckle noise is an inherent disturbance in coherent imaging systems such as digital holography, synthetic aperture radar, optical coherence tomography, or ultrasound systems. These systems usually produce only single observation per view…

Image and Video Processing · Electrical Eng. & Systems 2022-05-19 Tsung-Ming Tai , Yun-Jie Jhang , Wen-Jyi Hwang , Chau-Jern Cheng

Fluorescence imaging is an essential diagnostic tool in many fields, but diffraction-limited optical imaging at depth is limited by scattering. Here, we present a method based on multiple random illuminations, combined with a computational…

Optics · Physics 2026-03-30 Lei Zhu , Tengfei Wu , Bernhard Rauer , Hilton B. de Aguiar , Sylvain Gigan

A new technique is presented for producing images from interferometric data. The method, ``smear fitting'', makes the constraints necessary for interferometric imaging double as a model, with uncertainties, of the sky brightness…

Astrophysics · Physics 2009-11-11 Robert I. Reid

In recent years, there has been a proliferation of wide-field sky surveys to search for a variety of transient objects. Using relatively short focal lengths, the optics of these systems produce undersampled stellar images often marred by a…

Astrophysics · Physics 2009-11-13 Fang Yuan , Carl W. Akerlof

The spatial coherence wavefront outer scale (L_0) characterizes the size of the largest turbulence eddies in Earth's atmosphere, determining low spatial frequency perturbations in the wavefront of the light captured by ground-based…

Instrumentation and Methods for Astrophysics · Physics 2024-07-03 Begoña García-Lorenzo , Donaji Esparza-Arredondo , Jose A. Acosta-Pulido , Julio A. Castro-Almazán

Point Spread Function (PSF) for imaging through inhomogeneous refractive medium, such as atmospheric turbulence is bounded by three constraints [Charnotskii, Opt. Eng., 52, 04600, (2013)]. PSF is non-negative, band-limited, and the third…

Optics · Physics 2022-07-06 Mikhail Charnotskii

Incoherently illuminated or luminescent objects give rise to a low-contrast speckle-like pattern when observed through a thin diffusive medium, as such a medium effectively convolves their shape with a speckle-like point spread function…

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