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The performance of a wide-field adaptive optics system depends on input design parameters. Here we investigate the performance of a multi-object adaptive optics system design for the European Extremely Large Telescope, using an end-to-end…

Instrumentation and Methods for Astrophysics · Physics 2016-09-21 Alastair Basden , Tim Morris

The total variation method is widely used in image noise suppression. However, this method is easy to cause the loss of image details, and it is also sensitive to parameters such as iteration time. In this work, the total variation method…

Image and Video Processing · Electrical Eng. & Systems 2020-03-19 Shuo Huang , Suiren Wan

The total variation (TV) regularization has phenomenally boosted various variational models for image processing tasks. We propose to combine the backward diffusion process in the earlier literature of image enhancement with the TV…

Image and Video Processing · Electrical Eng. & Systems 2023-06-14 Congpei An , Hao-Ning Wu , Xiaoming Yuan

This contribution deals with image restoration in optical systems with coherent illumination, which is an important topic in astronomy, coherent microscopy and radar imaging. Such optical systems suffer from wavefront distortions, which are…

Instrumentation and Methods for Astrophysics · Physics 2017-04-04 Claudius Zelenka , Reinhard Koch

This study presents the development of a spatially adaptive weighting strategy for Total Variation regularization, aimed at addressing under-determined linear inverse problems. The method leverages the rapid computation of an accurate…

Numerical Analysis · Mathematics 2025-01-20 Elena Morotti , Davide Evangelista , Andrea Sebastiani , Elena Loli Piccolomini

Quantum noise limits the sensitivity of precision measurement devices, such as laser interferometer gravitational-wave observatories and axion detectors. In the shot-noise-limited regime, these resonant detectors are subject to a trade-off…

Quantum Physics · Physics 2021-06-16 Xiang Li , Jiri Smetana , Amit Singh Ubhi , Joe Bentley , Yanbei Chen , Yiqiu Ma , Haixing Miao , Denis Martynov

Respiratory sound classification is hindered by the limited size, high noise levels, and severe class imbalance of benchmark datasets like ICBHI 2017. While Transformer-based models offer powerful feature extraction capabilities, they are…

Audio and Speech Processing · Electrical Eng. & Systems 2025-12-30 Atakan Işık , Selin Vulga Işık , Ahmet Feridun Işık , Mahşuk Taylan

Quantum mechanics for many-body systems may be reduced to the evaluation of integrals in 3N dimensions using Monte-Carlo, providing the Quantum Monte Carlo ab initio methods. Here we limit ourselves to expectation values for trial…

Computational Physics · Physics 2010-11-22 John Robert Trail , Ryo Maezono

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang

Real-time seeing and outer scale estimation at the location of the focus of a telescope is fundamental for the adaptive optics systems dimensioning and performance prediction, as well as for the operational aspects of instruments. This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Patrice Martinez

Extreme adaptive optics systems are now in operation across the globe. These systems, capable of high order wavefront correction, deliver Strehl ratios of 90% in the near-infrared. Originally intended for the direct imaging of exoplanets,…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 Nemanja Jovanovic , Christian Schwab , Nick Cvetojevic , Olivier Guyon , Frantz Martinache

Pixels in image sensors have progressively become smaller, driven by the goal of producing higher-resolution imagery. However, ceteris paribus, a smaller pixel accumulates less light, making image quality worse. This interplay of…

Computer Vision and Pattern Recognition · Computer Science 2025-07-08 Anqi Yang , Eunhee Kang , Wei Chen , Hyong-Euk Lee , Aswin C. Sankaranarayanan

We present a liquid crystal method of correcting the phase of an aberrated wavefront using a spatial light modulator. A simple and efficient lab model has been demonstrated for wavefront correction. The crux of a wavefront correcting system…

Instrumentation and Methods for Astrophysics · Physics 2009-10-11 Akondi Vyas , M. B. Roopashree , Ravinder Kumar Banyal , B. Raghavendra Prasad

The highest three-dimensional (3D) resolution possible in in-vivo retinal imaging is achieved by combining optical coherence tomography (OCT) and adaptive optics (AO). However, this combination brings important limitations, such as small…

Medical Physics · Physics 2020-10-21 Jules Scholler , Kassandra Groux , Kate Grieve , Claude Boccara , Pedro Mecê

We demonstrate a wavefront sensor based on the compressive sensing, single-pixel camera. Using a high-resolution spatial light modulator (SLM) as a variable waveplate, we weakly couple an optical field's transverse-position and polarization…

Optics · Physics 2014-07-30 Gregory A. Howland , Daniel J. Lum , John C. Howell

This chapter gives an overview over recovery guarantees for total variation minimization in compressed sensing for different measurement scenarios. In addition to summarizing the results in the area, we illustrate why an approach that is…

Information Theory · Computer Science 2017-11-06 Felix Krahmer , Christian Kruschel , Michael Sandbichler

Phase estimates in adaptive-optics systems are computed by use of wavefront sensors such as Shack-Hartmann or curvature sensors. In either case the standard error of the phase estimates is proportional to the standard error of the…

Instrumentation and Detectors · Physics 2015-05-27 A. N. Kellerer , A. M. Kellerer

Sharpness-Aware Minimization (SAM) optimizer enhances the generalization ability of the machine learning model by exploring the flat minima landscape through weight perturbations. Despite its empirical success, SAM introduces an additional…

Machine Learning · Computer Science 2025-06-02 Yifei Cheng , Li Shen , Hao Sun , Nan Yin , Xiaochun Cao , Enhong Chen

Adaptive optics systems correct atmospheric turbulence in real time. Most adaptive optics systems used routinely correct in the near infrared, at wavelengths greater than 1 micron. MagAO- X is a new extreme adaptive optics (ExAO) instrument…

Nitrogen-vacancy (NV) centers in diamond are suitable sensors of high-sensitivity magnetometry which have attracted much interest in recent years. Here, we demonstrate sensitivity-enhanced ensembles magnetometry via adaptively complete…

Quantum Physics · Physics 2022-12-21 Bao Chen , Bing Chen , Xinyi Zhu , Zhifei Yu , Peng Qian , Nanyang Xu