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Due to turbulence in the atmosphere images taken from ground-based telescopes become distorted. With adaptive optics (AO) images can be given greater clarity allowing for better observations with existing telescopes and are essential for…

Instrumentation and Methods for Astrophysics · Physics 2023-08-30 Javier Perez Soto , Cesar Laguna , Benjamin L. Gerard , Anne Dattilo , Vincent Chambouleyron , Rebecca Jensen-Clem

Wavefront reconstruction in lateral shearing interferometry typically assumes that the shear amount is an integer multiple of the sampling interval. When the shear is fractional, approximating it with the nearest integer value leads to…

Robo-AO is an autonomous laser guide star adaptive optics system recently commissioned at the Kitt Peak 2.1-m telescope. Now operating every clear night, Robo-AO at the 2.1-m telescope is the first dedicated adaptive optics observatory.…

Instrumentation and Methods for Astrophysics · Physics 2017-12-27 Rebecca Jensen-Clem , Dmitry A. Duev , Reed Riddle , Maïssa Salama , Christoph Baranec , Nicholas M. Law , S. R. Kulkarni , A. N. Ramprakash

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

We present a direct method for limited angle tomographic reconstruction using convolutional networks. The key to our method is to first stretch every tilt view in the direction perpendicular to the tilt axis by the secant of the tilt angle.…

Image and Video Processing · Electrical Eng. & Systems 2023-06-21 Kyle Luther , Sebastian Seung

We present a promising approach to the extremely fast sensing and correction of small wavefront errors in adaptive optics systems. As our algorithm's computational complexity is roughly proportional to the number of actuators, it is…

Instrumentation and Methods for Astrophysics · Physics 2016-11-26 Christoph U. Keller , Visa Korkiakoski , Niek Doelman , Rufus Fraanje , Raluca Andrei , Michel Verhaegen

Recently, a novel measurement setup has been introduced to photoacoustic tomography, that collects data in the form of projections of the full 3D acoustic pressure distribution at a certain time instant. Existing imaging algorithms for this…

Numerical Analysis · Mathematics 2018-08-03 Gerhard Zangerl , Markus Haltmeier , Linh V. Nguyen , Robert Nuster

An holographic microscopy reconstruction method compatible with high numerical aperture microscope objective (MO) up to NA=1.4 is proposed. After off axis and reference field curvature corrections, and after selection of the +1 grating…

Optics · Physics 2015-11-16 Nicolas Verrier , Dario Donnarumma , Gilles Tessier , Michel Gross

Advanced wavefront sensors (WFS) are essential for enabling new science cases for telescopes that utilize adaptive optics (AO) systems. While complex field WFS -- those that estimate the electric field phase and amplitude through…

Instrumentation and Methods for Astrophysics · Physics 2025-08-21 D. Angelica Huerta , Justin R. Crepp , Caleb G. Abbott , Brian Joseph

This work proposes the use of orbital angular momentum (OAM) waves to improve the performance of a computational imaging (CI) system. Specifically, in contrast to a solely frequency-diverse operation, leveraging multiple OAM waves leads to…

Astrometric precision and knowledge of the point spread function are key ingredients for a wide range of astrophysical studies including time-delay cosmography in which strongly lensed quasar systems are used to determine the Hubble…

Instrumentation and Methods for Astrophysics · Physics 2021-09-22 Geoff C. -F. Chen , Tommaso Treu , Christopher D. Fassnacht , Sam Ragland , Thomas Schmidt , Sherry H. Suyu

The strength and vertical distribution of atmospheric turbulence is a key factor determining the performance of optical and infrared telescopes, with and without adaptive optics. Yet, this remains challenging to measure. We describe a new…

Instrumentation and Methods for Astrophysics · Physics 2019-10-11 Paul Hickson , Bin Ma , Zhaohui Shang , Suijian Xue

We present a near real-time solution for 3D reconstruction from aerial images captured by consumer UAVs. Our core idea is to simplify the multi-view stereo problem into a series of two-view stereo matching problems. Our method applies to…

Computational Geometry · Computer Science 2019-02-27 Qiaosong Wang

Time-of-flight positron emission tomography (TOF-PET) detectors exhibiting multiple coincidence time resolution (CTR) components, such as those induced by the mixing of Cherenkov and scintillation photons, have attracted increasing…

Medical Physics · Physics 2026-05-29 Kibo Ote , Fumio Hashimoto , Yuya Onishi , Ryosuke Ota , Maxime Toussaint , Francis Loignon-Houle

The Fast Proximal Gradient Method (FPGM) and the Monotone FPGM (MFPGM) for minimization of nonsmooth convex functions are introduced and applied to tomographic image reconstruction. Convergence properties of the sequence of objective…

Optimization and Control · Mathematics 2020-08-25 Elias S. Helou , Marcelo V. W. Zibetti , Gabor T. Herman

We study a simple modification to the conventional time of flight mass spectrometry (TOFMS) where a \emph{variable} and (pseudo)-\emph{random} pulsing rate is used which allows for traces from different pulses to overlap. This modification…

Optimization and Control · Mathematics 2013-07-30 Morteza Ibrahimi , Andrea Montanari , George S Moore

Even though the technology of adaptive optics (AO) is rapidly maturing, calibration of the resulting images remains a major challenge. The AO point-spread function (PSF) changes quickly both in time and position on the sky. In a typical…

Adaptive Optics (AO) is an innovative technique that substantially improves the optical performance of ground-based telescopes. The SOAR Adaptive Module (SAM) is a laser-assisted AO instrument, designed to compensate ground-layer…

Instrumentation and Methods for Astrophysics · Physics 2018-08-28 D. M. Faes , A. Tokovinin , T. Vieira , A. Mello , M. Domingues , D. Andrade , B. C. Quint , J. B. Santos

We introduce a novel weather-adaptive approach for multi-step forecasting of multi-scale SOP changes in aerial fiber links. By harnessing the discrete wavelet transform and incorporating weather data, our approach improves forecasting…

Networking and Internet Architecture · Computer Science 2024-09-06 Khouloud Abdelli , Matteo Lonardi , Jurgen Gripp , Samuel Olsson Fabien Boitier , Patricia Layec

The use of Time Of Flight (TOF) in Positron Emission Tomography (PET) is expected to reduce noise on images, thanks to the additional information. In clinical routine, a common reconstruction approach is the use of maximum likelihood…

Medical Physics · Physics 2019-10-16 Luca Presotto , Elisabetta De Bernardi , Valentino Bettinardi