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We proposed a real time Total-Variation denosing method with an automatic choice of hyper-parameter $\lambda$, and the good performance of this method provides a large application field. In this article, we adapt the developed method to the…

Signal Processing · Electrical Eng. & Systems 2021-01-29 Zhanhao Liu , Marion Perrodin , Thomas Chambrion , Radu Stoica

Stellar intensity interferometers will achieve stellar imaging with a tenth of a milli- arcsecond resolution in the optical band by taking advantage of the large light collect- ing area and broad range of inter-telescope distances offered…

Instrumentation and Methods for Astrophysics · Physics 2013-03-19 Janvida Rou , Paul D. Nuñez , David Kieda , Stephan LeBohec

To directly image Earth-like planets, contrast levels of 10^-8 - 10^-10 are required. The next generation of instruments will need wavefront control below the nanometer level to achieve these goals. The Zernike wavefront sensor (ZWFS) is a…

Instrumentation and Methods for Astrophysics · Physics 2025-10-01 M. Darcis , S. Y. Haffert , V. Chambouleyron , D. S. Doelman , P. J. de Visser , M. A. Kenworthy

Monitoring turbulence parameters is crucial in high-angular resolution astronomy for various purposes, such as optimising adaptive optics systems or fringe trackers. The former are present at most modern observatories and will remain…

Instrumentation and Methods for Astrophysics · Physics 2023-10-25 Nuno Morujão , Carlos Correia , Paulo Andrade , Julien Woillez , Paulo Garcia

Current designs for all three extremely large telescopes show the overwhelming adoption of the pyramid wavefront sensor (P-WFS) as the WFS of choice for adaptive optics (AO) systems sensing on natural guide stars (NGS) or extended objects.…

Multi-object adaptive optics (MOAO) has been demonstrated by the CANARY instrument on the William Herschel Telescope. However, for proposed MOAO systems on the next generation Extremely Large Telescopes, such as EAGLE, many challenges…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 A. G. Basden , N. A. Bharmal , R. M. Myers , S. L. Morris , T. J. Morris

The estimation and compensation of quasi-static aberrations is mandatory to reach the ultimate performance of high-contrast imaging systems. COFFEE is a focal plane wave-front sensing method that consists in the extension of phase diversity…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 B. Paul , L. M. Mugnier , J. -F. Sauvage , K. Dohlen

The increased use of low-cost gyroscopes within inertial sensors for navigation purposes, among others, has brought to the development of a considerable amount of research in improving their measurement precision. Aside from developing…

Applications · Statistics 2021-07-01 Yuming Zhang , Davide A. Cucci , Roberto Molinari , Stéphane Guerrier

Shack-Hartmann wavefront sensing relies on accurate spot centre measurement. Several algorithms were developed with this aim, mostly focused on precision, i.e. minimizing random errors. In the solar and extended scene community, the…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 Narsireddy Anugu , Paulo J. V. Garcia , Carlos M. Correia

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

Deploying Vision Transformers (ViTs) on near-sensor analog accelerators demands training pipelines that are explicitly aligned with device-level noise and energy constraints. We introduce a compact framework for silicon-photonic execution…

Emerging Technologies · Computer Science 2026-04-07 Xuming Chen , Deniz Najafi , Chengwei Zhou , Pietro Mercati , Arman Roohi , Mohsen Imani , Mahdi Nikdast , Shaahin Angizi , Gourav Datta

Confocal Raman microscopy, a highly specific and label-free technique for the microscale study of thick samples, often presents difficulties due to weak Raman signals. Inhomogeneous samples introduce wavefront aberrations that further…

Digital co-addition of astronomical images is a common technique for increasing signal-to-noise and image depth. A modification of this simple technique has been applied to the detection of minor bodies in the Solar System: first stationary…

Earth and Planetary Astrophysics · Physics 2015-05-18 Alex H. Parker , JJ. Kavelaars

Images obtained by microscopes are generally degraded by aberrations. Adaptive optics (AO) has been widely used in to compensate for aberrations and improve reduced image quality. Requiring no separate wavefront sensor, sensorless AO…

Optics · Physics 2025-09-23 Biwei Zhang , Qi Hu , Jingyu Wang , Martin J. Booth

We consider variational inequalities coming from monotone operators, a setting that includes convex minimization and convex-concave saddle-point problems. We assume an access to potentially noisy unbiased values of the monotone operators…

Machine Learning · Computer Science 2019-02-06 Francis Bach , Kfir Y. Levy

We present a novel variational approach to image restoration (e.g., denoising, inpainting, labeling) that enables to complement established variational approaches with a histogram-based prior enforcing closeness of the solution to some…

Optimization and Control · Mathematics 2013-07-18 Paul Swoboda , Christoph Schnörr

We report an extensive numerical study and supporting experimental results on the spectral characterization of optical aberrations in macroscopic fluidic lenses with tunable focal distance and aperture shape. Using a Shack-Hartmann…

Optics · Physics 2023-12-19 Graciana Puentes , Fernando Minotti

Consistent operation of adaptive optics (AO) systems requires the use of a wavefront sensor (WFS) with high sensitivity and low noise. The nonlinear curvature WFS (nlCWFS) has been shown both in simulations and lab experiments to be more…

Instrumentation and Methods for Astrophysics · Physics 2023-12-05 Sam Potier , Justin Crepp , Stanimir Letchev

We present an experimental test of the use of stress engineered optics incorporated into a Shack-Hartmann wavefront sensor in such a way that the shape of the point spread function (PSF) provides polarization information while the…

Instrumentation and Detectors · Physics 2026-03-17 David E. Spiecker , Thomas G. Brown

Super-resolution (SR) refers to a combination of optical design and signal processing techniques jointly employed to obtain reconstructed wave-fronts at a higher-resolution from multiple low-resolution samples, overcoming the intrinsic…

Instrumentation and Methods for Astrophysics · Physics 2025-12-22 Carlos M. Correia , Charlotte Z. Bond , João Aveiro , François Leroux , Cédric Taïssir Heritier , Christophe Vérinaud
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