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Related papers: Sparse Image Reconstruction for the SPIDER Optical…

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A new principle of subwavelength imaging based on frequency scanning is considered. It is shown that it is possible to reconstruct the spatial profile of an external field exciting an array (or coupled arrays) of subwavelength-sized…

Optics · Physics 2008-06-27 Stanislav Maslovski , Pekka Alitalo , Sergei Tretyakov

Inferring sky surface brightness distributions from noisy interferometric data in a principled statistical framework has been a key challenge in radio astronomy. In this work, we introduce Imaging for Radio Interferometry with Score-based…

Instrumentation and Methods for Astrophysics · Physics 2025-01-07 Noé Dia , M. J. Yantovski-Barth , Alexandre Adam , Micah Bowles , Laurence Perreault-Levasseur , Yashar Hezaveh , Anna Scaife

Nowadays, analyzing and reducing the ever larger astronomical datasets is becoming a crucial challenge, especially for long cumulated observation times. The INTEGRAL/SPI X-gamma-ray spectrometer is an instrument for which it is essential to…

Instrumentation and Methods for Astrophysics · Physics 2013-05-27 L. Bouchet , P. Amestoy , A. Buttari , F. -H. Rouet , M. Chauvin

The detection and characterisation of extra-solar planets is a major theme driving modern astronomy, with the vast majority of such measurements being achieved by Doppler radial-velocity and transit observations. Another technique -- direct…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Barnaby Norris , Nick Cvetojevic , Simon Gross , Nemanja Jovanovic , Paul N. Stewart , Ned Charles , Jon S. Lawrence , Michael J. Withford , Peter Tuthill

SPIDER is a balloon-borne instrument designed to map the cosmic microwave background at degree-angular scales in the presence of Galactic foregrounds. SPIDER has mapped a large sky area in the Southern Hemisphere using more than 2000…

Faraday tomography (or rotation measure synthesis) is a procedure to convert linear polarization spectra into the Faraday dispersion function, which provides us with unique information of magneto-ionic media along the line of sight.…

Instrumentation and Methods for Astrophysics · Physics 2018-12-03 Kazunori Akiyama , Takuya Akahori , Yoshimitsu Miyashita , Shinsuke Ideguchi , Ryosuke Yamaguchi , Shiro Ikeda , Keitaro Takahashi

Sparse representation of astronomical images is discussed. It is shown that a significant gain in sparsity is achieved when particular mixed dictionaries are used for approximating these types of images with greedy selection strategies.…

Mathematical Physics · Physics 2015-06-11 Laura Rebollo-Neira , James Bowley

A novel interferometric method - SLIVER (Super Localization by Image inVERsion interferometry) - is proposed for estimating the separation of two incoherent point sources with a mean squared error that does not deteriorate as the sources…

Optics · Physics 2016-02-16 Ranjith Nair , Mankei Tsang

We present a fast and accurate method for dense depth reconstruction from sparsely sampled light fields obtained using a synchronized camera array. In our method, the source images are over-segmented into non-overlapping compact superpixels…

Image and Video Processing · Electrical Eng. & Systems 2018-12-18 Aleksandra Chuchvara , Attila Barsi , Atanas Gotchev

Spatial Heterodyne Spectroscopy (SHS) is a relatively novel interferometric technique similar to the Fourier transform spectroscopy with heritage from the Michelson Interferometer. An imaging detector is used at the output of a SHS to…

Photoacoustic tomography is a hybrid biomedical technology, which combines the advantages of acoustic and optical imaging. However, for the conventional image reconstruction method, the image quality is affected obviously by artifacts under…

Image and Video Processing · Electrical Eng. & Systems 2024-06-26 Bowei Yao , Yi Zeng , Haizhao Dai , Qing Wu , Youshen Xiao , Fei Gao , Yuyao Zhang , Jingyi Yu , Xiran Cai

Given the incomplete sampling of spatial frequencies by radio interferometers, achieving precise restoration of astrophysical information remains challenging. To address this ill-posed problem, compressive sensing(CS) provides a robust…

Instrumentation and Methods for Astrophysics · Physics 2025-05-09 Lei Yu , Bin Liu , Cheng-Jin Jin , Ru-Rong Chen , Hong-Wei Xi , Bo Peng

In traditional optical imaging systems, the spatial resolution is limited by the physics of diffraction, which acts as a low-pass filter. The information on sub-wavelength features is carried by evanescent waves, never reaching the camera,…

Optics · Physics 2018-12-13 Oren Solomon , Yonina C. Eldar , Maor Mutzafi , Mordechai Segev

The direct imaging and characterization of Earth-like planets is among the most sought-after prizes in contemporary astrophysics, however current optical instrumentation delivers insufficient dynamic range to overcome the vast contrast…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 T. Kotani , S. Lacour , G. Perrin , G. Robertson , P. Tuthill

Imaging in a broad light-intensity regime with a high signal-to-noise ratio is a key capability in fields as diverse as Quantum Metrology and Astronomy. Achieving high signal-to-noise ratios in quantum imaging leads to surpassing the…

Instrumentation and Detectors · Physics 2023-01-27 Q. Pears Stefano , A. G. Magnoni , J. Estrada , C. Iemmi , D. Rodrigues , J. Tiffenberg

Integral Field Spectroscopy (IFS) is a technique that gives simultaneously the spectrum of each spatial sampling element in a given object field. It is a powerful tool which rearranges the data cube (x, y, lambda) represented by two spatial…

Instrumentation and Methods for Astrophysics · Physics 2016-12-07 Florence Laurent , Francois Henault

The next generation of adaptive optics (AO) systems will require tomographic reconstruction techniques to map the optical refractive index fluctuations, generated by the atmospheric turbulence, along the line of sight to the astronomical…

Instrumentation and Methods for Astrophysics · Physics 2014-01-07 H. W. Shepherd , J. Osborn , R. W. Wilson , T. Butterley , R. Avila , V. S. Dhillon , T. J. Morris

Optical imaging of quantum emitters is essential for a wide range of quantum applications. Conventional confocal imaging relies on point-by-point raster scanning, which is inherently time-consuming and photon-inefficient, particularly for…

We propose a new method for reconstruction of sparse signals with and without noisy perturbations, termed the subspace pursuit algorithm. The algorithm has two important characteristics: low computational complexity, comparable to that of…

Numerical Analysis · Computer Science 2009-01-08 Wei Dai , Olgica Milenkovic

Speckle Imaging based on triple correlation is a very efficient image reconstruction technique which is used to retrieve Fourier phase information of the object in presence of atmospheric turbulence. We have developed both Direct Bispectrum…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha