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Fourier optical processing underpins optical information manipulation, yet extending such operations to short wavelengths within compact platforms remains challenging. Here, we address this challenge by embedding reconfigurable…

Atmospheric turbulence causes fluctuations in the local refractive index of air that accumulatively disturb a wave's phase and amplitude distribution as it propagates. This impairs the effective range of laser weapons as well as the…

Optics · Physics 2015-06-02 Chensheng Wu , Jonathan Ko , Christopher C. Davis

AOLI (Adaptive Optics Lucky Imager) is a state-of-art instrument that combines adaptive optics (AO) and lucky imaging (LI) with the objective of obtaining diffraction limited images in visible wavelength at mid- and big-size ground-based…

Wavefront sensors have now become core components in the fields of metrology of optical systems, biomedical optics, and adaptive optics systems for astronomy. However, none of the designs used or proposed so far achieve simultaneously a…

Optics · Physics 2024-07-04 F. Henault , Y. Feng , J. -J. Correia , L. Schreiber , A. Spang

In biological microscopy, light scattering represents the main limitation to image at depth. Recently, a set of wavefront shaping techniques has been developed in order to manipulate coherent light in strongly disordered materials. The…

Optics · Physics 2021-01-07 Antoine Boniface , Jonathan Dong , Sylvain Gigan

Full waveform inversion (FWI) is an iterative nonlinear waveform matching procedure subject to wave-equation constraint. FWI is highly nonlinear when the wave-equation constraint is enforced at each iteration. To mitigate nonlinearity,…

Optimization and Control · Mathematics 2019-10-29 Hossein S. Aghamiry , Ali Gholami , Stephane Operto

With the Extremely Large Telescope-generation telescopes come new challenges. The complexity of these telescopes' pupil creates new problems for Adaptive Optics. In particular, the large spiders necessary to support the massive optics of…

All coronagraphic instruments for exoplanet high-contrast imaging need wavefront correction systems to reject optical aberrations and create sufficiently dark holes. Since the most efficient wavefront correction algorithms (controllers and…

Instrumentation and Methods for Astrophysics · Physics 2018-10-09 He Sun , N. Jeremy Kasdin , Robert Vanderbei

The new class of large telescopes, as the future ELT, are designed to work with Laser Guide Star (LGS) tuned to a resonance of atmosphere sodium atoms. This wavefront sensing technique presents complex issues for an application to big…

Instrumentation and Methods for Astrophysics · Physics 2018-04-20 M. Patti , M. Lombini , L. Schreiber , G. Bregoli , C. Arcidiacono , G. Cosentino , E. Diolaiti , I. Foppiani

Adaptive optics is a technique mostly used on large telescopes. It turns out to be challenging for smaller telescopes (0.5~2m) due to the small isoplanatic angle, small subapertures and high correction speeds needed at visible wavelengths,…

Instrumentation and Methods for Astrophysics · Physics 2023-10-12 Olivier Lai , Mark Chun , Stefan Kuiper , Niek Doelman , Marcel Carbillet , Mamadou N'Diaye , Frantz Martinache , Lyu Abe , Jean-Pierre Rivet , Dirk Schmidt

Elastic full-waveform inversion (EFWI) is a process used to estimate subsurface properties by fitting seismic data while satisfying wave propagation physics. The problem is formulated as a least-squares data fitting minimization problem…

Numerical Analysis · Mathematics 2024-04-12 Kamal Aghazade , Ali Gholami , Hossein S. Aghamiry , Hamid Reza Siahkoohi

Laser guide star (LGS) wave-front sensing (LGSWFS) is a key element of tomographic adaptive optics system. However, when considering Extremely Large Telescope (ELT) scales, the LGS spot elongation becomes so large that it challenges the…

The photonic lantern (PL) is a tapered waveguide that can efficiently couple light into multiple single-mode optical fibers. Such devices are currently being considered for a number of tasks, including the coupling of telescopes and…

Instrumentation and Methods for Astrophysics · Physics 2022-09-28 Jonathan Lin , Michael Fitzgerald , Yinzi Xin , Olivier Guyon , Sergio Leon-Saval , Barnaby Norris , Nemanja Jovanovic

This paper is the third part of a trilogy dealing with the principles, performance and limitations of what I named "Telescope-Interferometers" (TIs). The basic idea consists in transforming one telescope into a Wavefront Error (WFE) sensing…

Optics · Physics 2011-05-17 Francois Henault

The ingot wavefront sensor (I-WFS) has been proposed, for ELT-like apertures, as a possible pupil plane WFS, to cope with the geometrical characteristics of a laser guide star (LGS). Within the study and development of such a WFS, on-going…

Wavefront shaping correction makes it possible to image fluorescent particles deep inside scattering tissue. This requires determining a correction mask to be placed in both excitation and emission paths. Standard approaches select…

Optics · Physics 2022-06-22 Dror Aizik , Ioannis Gkioulekas , Anat Levin

The James Webb Space Telescope is orders of magnitude more sensitive than any other facility across the near to mid-infrared wavelengths. Many approved programs take advantage of its highly stable point spread function (PSF) to directly…

We extend our previous demonstration of the first on-sky primary mirror segment closed-loop control on Keck using a vector-Zernike wavefront sensor (vZWFS), which improved the Strehl ratio on the NIRC2 science camera by up to 10 percentage…

This paper presents the basic principle and theoretical relationships of an original method allowing to retrieve the Wavefront Errors (WFE) of a ground or space-borne telescope when combining its main pupil with a second, decentered…

Optics · Physics 2011-05-19 Francois Henault

Astronomical adaptive optics systems with open-loop deformable mirror control have recently come on-line. In these systems, the deformable mirror surface is not included in the wavefront sensor paths, and so changes made to the deformable…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Alastair Basden , Richard Myers , Eric Gendron