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REDWOODS on ShaneAO at Lick Observatory implements a second-stage, 3-sided reflective pyramid wavefront sensor (PWFS), which, under low-light conditions, offers an improved signal-to-noise ratio for deformable mirror commands to correct…

Instrumentation and Methods for Astrophysics · Physics 2025-08-21 Joel Hurtado , Benjamin Gerard , Cesar Laguna , Dominic Francisco Sanchez

Convolutional neural networks (CNNs) have shown remarkable performance in various computer vision tasks in recent years. However, the increasing model size has raised challenges in adopting them in real-time applications as well as mobile…

Computer Vision and Pattern Recognition · Computer Science 2018-11-20 Van-Thanh Hoang , Kang-Hyun Jo

We present a reference-free computational wavefront sensor based on binary amplitude modulation and phase retrieval. The method employs Digital Micro-mirror Device as a programmable amplitude modulator and reconstructs the complex optical…

Optics · Physics 2026-02-12 Ondrej Denk , Jan Pilar , Martin Divoky , Miroslav Cech , Tomas Mocek

Wavefront sensors (WFS) are now core components in the fields of metrology of optical systems, biomedical optics and adaptive optics systems for astronomy. Nowadays, the most popular WFS is the Shack-Hartmann, which is fully static but…

Optics · Physics 2025-07-21 Francois Hénault , Yan Feng , Alain Spang , Laura Schreiber

In ground-based astronomy, Adaptive Optics (AO) is a pivotal technique, engineered to correct wavefront phase distortions and thereby enhance the quality of the observed images. Integral to an AO system is the wavefront sensor (WFS), which…

Instrumentation and Methods for Astrophysics · Physics 2026-05-07 Yutong Wu , Roland Wagner , Ronny Ramlau , Raymond H. Chan

A new deep neural network based on the WaveNet architecture (WNN) is presented, which is designed to grasp specific patterns in the NMR spectra. When trained at a fixed non-uniform sampling (NUS) schedule, the WNN benefits from pattern…

Biomolecules · Quantitative Biology 2022-12-05 Amir Jahangiri , Xiao Han , Dmitry Lesovoy , Tatiana Agback , Peter Agback , Adnane Achour , Vladislav Orekhov

Although using convolutional neural networks (CNNs) as backbones achieves great successes in computer vision, this work investigates a simple backbone network useful for many dense prediction tasks without convolutions. Unlike the…

Computer Vision and Pattern Recognition · Computer Science 2021-08-12 Wenhai Wang , Enze Xie , Xiang Li , Deng-Ping Fan , Kaitao Song , Ding Liang , Tong Lu , Ping Luo , Ling Shao

We present numerical characterizations of the wavefront sensing performance for few-mode photonic lantern wavefront sensors (PLWFSs). These characterizations include calculations of throughput, control space, sensor linearity, and an…

Instrumentation and Methods for Astrophysics · Physics 2023-11-06 Jonathan Lin , Michael P. Fitzgerald , Yinzi Xin , Yoo Jung Kim , Olivier Guyon , Sergio Leon-Saval , Barnaby Norris , Nemanja Jovanovic

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

Wavefront sensors encode phase information of an incoming wavefront into an intensity pattern that can be measured on a camera. Several kinds of wavefront sensors (WFS) are used in astronomical adaptive optics. Amongst them, Fourier-based…

Feature pyramid networks (FPN) are widely exploited for multi-scale feature fusion in existing advanced object detection frameworks. Numerous previous works have developed various structures for bidirectional feature fusion, all of which…

Computer Vision and Pattern Recognition · Computer Science 2021-10-26 Zhuofan Zong , Qianggang Cao , Biao Leng

The Moore-Penrose Pseudo-inverse (PInv) serves as the fundamental solution for linear systems. In this paper, we propose a natural generalization of PInv to the nonlinear regime in general and to neural networks in particular. We introduce…

Machine Learning · Computer Science 2026-02-06 Yamit Ehrlich , Nimrod Berman , Assaf Shocher

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…

Blind image restoration processors based on convolutional neural network (CNN) are intensively researched because of their high performance. However, they are too sensitive to the perturbation of the degradation model. They easily fail to…

Computer Vision and Pattern Recognition · Computer Science 2018-09-12 Kazutaka Uchida , Masayuki Tanaka , Masatoshi Okutomi

Full waveform inversion (FWI) is a powerful tool for reconstructing material fields based on sparsely measured data obtained by wave propagation. For specific problems, discretizing the material field with a neural network (NN) improves the…

Machine Learning · Computer Science 2024-08-02 Divya Shyam Singh , Leon Herrmann , Qing Sun , Tim Bürchner , Felix Dietrich , Stefan Kollmannsberger

This work introduces pyramidal convolution (PyConv), which is capable of processing the input at multiple filter scales. PyConv contains a pyramid of kernels, where each level involves different types of filters with varying size and depth,…

Computer Vision and Pattern Recognition · Computer Science 2020-06-23 Ionut Cosmin Duta , Li Liu , Fan Zhu , Ling Shao

Physics-informed neural networks (PINNs) and neural operators (NOs) for solving the problem of diffraction of Extreme Ultraviolet (EUV) electromagnetic waves from contemporary lithography masks are presented. A novel hybrid Waveguide Neural…

Machine Learning · Computer Science 2026-03-18 Vasiliy A. Es'kin , Egor V. Ivanov

The advent of deep-learning-based registration networks has addressed the time-consuming challenge in traditional iterative methods.However, the potential of current registration networks for comprehensively capturing spatial relationships…

Computer Vision and Pattern Recognition · Computer Science 2024-02-15 Zhuoyuan Wang , Haiqiao Wang , Yi Wang

Several telescopes include large Deformable Mirrors (DM) located directly inside the telescope. These adaptive telescopes trigger new constraints for the calibration of the Adaptive Optics (AO) systems as they usually offer no access to an…

Instrumentation and Methods for Astrophysics · Physics 2019-01-10 C. T. Heritier , S. Esposito , T. Fusco , B. Neichel , S. Oberti , R. Briguglio , G. Agapito , A. Puglisi , E. Pinna , P. -Y. Madec

High-contrast imaging instruments need extreme wavefront control to directly image exoplanets. This requires highly sensitive wavefront sensors which optimally make use of the available photons to sense the wavefront. Here, we propose to…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Rico Landman , Christoph Keller , Emiel H. Por , Sebastiaan Haffert , David Doelman , Thijs Stockmans