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Related papers: Peak-locking centroid bias in Shack-Hartmann wavef…

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High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky…

Instrumentation and Methods for Astrophysics · Physics 2021-07-19 Steven P. Bos , Michael Bottom , Sam Ragland , Jacques-Robert Delorme , Sylvain Cetre , Laurent Pueyo

Synthetic aperture sonar (SAS) requires precise time-of-flight measurements of the transmitted/received waveform to produce well-focused imagery. It is not uncommon for errors in these measurements to be present resulting in image…

Computer Vision and Pattern Recognition · Computer Science 2021-06-02 Isaac D. Gerg , Vishal Monga

Conventional methods of wavefront reconstruction from the raw data of the Shack-Hartmann sensor use the focal spot shifts and discard the high-frequency information about the wavefront. Phase-retrieval-based methods treat the Hartmann…

Direct imaging of exoplanets relies on complex wavefront sensing and control architectures. In addition to fast adaptive optics systems, most of the future high-contrast imaging instruments will soon be equipped with focal plane wavefront…

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

The development of large-area homogeneous photo-detectors with sub-millimeter path lengths for direct Cherenkov light and for secondary-electrons opens the possibility of large time-of-flight systems for relativistic particles with…

Instrumentation and Detectors · Physics 2009-08-05 Jean-Francois Genat , Gary Varner , Fukun Tang , Henry Frisch

Most existing object detectors suffer from class imbalance problems that hinder balanced performance. In particular, anchor free object detectors have to solve the background imbalance problem due to detection in a per-pixel prediction…

Computer Vision and Pattern Recognition · Computer Science 2020-12-29 Hopyong Gil , Sangwoo Park , Yusang Park , Wongoo Han , Juyean Hong , Juneyoung Jung

Low-photon phase imaging is essential in applications where the signal is limited by short exposure times, faint targets, or the need to protect delicate samples. We address this challenge with Poisson Wavefront Imaging (PWI), an…

Due to their radiation hardness, kilohertz frame rates, and high dynamic range, hybrid pixel detectors have recently expanded their application range to electron diffraction and recently also electron imaging. However, these detectors…

Correlation Clustering (CC) is a foundational problem in unsupervised learning that models binary similarity relations using labeled graphs. While classical CC has been widely studied, many real-world applications involve more nuanced…

Data Structures and Algorithms · Computer Science 2025-09-23 Chenglin Fan , Dahoon Lee , Euiwoong Lee

This paper reexamines and fundamentally improves the Schmidl-and-Cox (S&C) algorithm, which is extensively used for packet detection in wireless networks, and enhances its adaptability for multi-antenna receivers. First, we introduce a new…

Networking and Internet Architecture · Computer Science 2023-07-12 Yuyang Du , Soung Chang Liew

There are two mainstreams for object detection: top-down and bottom-up. The state-of-the-art approaches mostly belong to the first category. In this paper, we demonstrate that the bottom-up approaches are as competitive as the top-down and…

Computer Vision and Pattern Recognition · Computer Science 2022-04-19 Kaiwen Duan , Song Bai , Lingxi Xie , Honggang Qi , Qingming Huang , Qi Tian

Large catalogs of shear-selected peaks have recently become a reality. In order to properly interpret the abundance and properties of these peaks, it is necessary to take into account the effects of the clustering of source galaxies, among…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Fabian Schmidt , Eduardo Rozo

This paper presents a new Bayesian model and associated algorithm for depth and intensity profiling using full waveforms from time-correlated single-photon counting (TCSPC) measurements in the limit of very low photon counts (i.e.,…

Instrumentation and Detectors · Physics 2016-10-14 Yoann Altmann , Ximing Ren , Aongus McCarthy , Gerald S. Buller , Steve McLaughlin

Exoplanet detection and characterization through extreme adaptive optics (ExAO) is a key science goal of future extremely large telescopes. This achievement, however, will be limited in sensitivity by both quasi-static wavefront errors and…

Earth and Planetary Astrophysics · Physics 2018-07-18 Benjamin L. Gerard , Christian Marois , Raphaël Galicher , Jean-Pierre Véran

This paper considers filters (the Mexican hat wavelet, the matched and the scale-adaptive filters) that optimize the detection/separation of point sources on a background. We make a one-dimensional treatment, we assume that the sources have…

Astrophysics · Physics 2009-11-07 R. B. Barreiro , J. L. Sanz , D. Herranz , E. Martinez-Gonzalez

It has previously been demonstrated in both simulation and experiment that well aligned remote focusing microscopes exhibit residual spherical aberration outside the focal plane. In this work, compensation of the residual spherical…

Optics · Physics 2023-05-17 Sharika Mohanan , Alexander D. Corbett

A method for producing a laser guide star wavefront sensor for adaptive optics with reduced focal anisoplanatism is presented. A theoretical analysis and numerical simulations have been carried out and the results are presented. The…

Astrophysics · Physics 2009-11-11 T. Butterley , G. D. Love , R. W. Wilson , R. M. Myers , T. J. Morris

This Point spread function (PSF) plays a crucial role in many computational imaging applications, such as shape from focus/defocus, depth estimation, and fluorescence microscopy. However, the mathematical model of the defocus process is…

Computer Vision and Pattern Recognition · Computer Science 2022-09-20 Renzhi He , Yan Zhuang , Boya Fu , Fei Liu

We present a novel solution to the camera pose estimation problem, where rotation and translation of a camera between two views are estimated from matched feature points in the images. The camera pose estimation problem is traditionally…

Computer Vision and Pattern Recognition · Computer Science 2018-07-31 Kaveh Fathian , J. Pablo Ramirez-Paredes , Emily A. Doucette , J. Willard Curtis , Nicholas R. Gans