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Focal plane wavefront sensing and control is a critical approach to reducing non-common path errors between the a conventional astronomical adaptive optics (AO) wavefront sensor (WFS) detector and science camera. However, in addition to…

Instrumentation and Methods for Astrophysics · Physics 2023-03-01 Benjamin L. Gerard , Daren Dillon , Sylvain Cetre , Rebecca Jensen-Clem

The search for exoplanets is pushing adaptive optics systems on ground-based telescopes to their limits. Currently, we are limited by two sources of noise: the temporal control error and non-common path aberrations. First, the temporal…

Super-resolution (SR) refers to a combination of optical design and signal processing techniques jointly employed to obtain reconstructed wave-fronts at a higher-resolution from multiple low-resolution samples, overcoming the intrinsic…

Instrumentation and Methods for Astrophysics · Physics 2025-12-22 Carlos M. Correia , Charlotte Z. Bond , João Aveiro , François Leroux , Cédric Taïssir Heritier , Christophe Vérinaud

Astronomers working with faint targets will benefit greatly from improved image quality on current and planned ground-based telescopes. At present, most adaptive optic systems are targeted at the highest resolution with bright guide stars.…

Instrumentation and Methods for Astrophysics · Physics 2020-01-30 Craig Mackay

Optical wavefront-shaping has emerged as a powerful tool to manipulate light in strongly scattering media. It enables diffraction-limited focusing and imaging at depths where conventional microscopy techniques fail. However, while most…

Optics · Physics 2014-03-04 T. Chaigne , O. Katz , A. C. Boccara , M. Fink , E. Bossy , S. Gigan

Wavefront of light passing through turbulent atmosphere gets distorted. This causes signal loss in free-space optical communication as the light beam spreads and wanders at the receiving end. Frequency and/or time division multiplexing…

Quantum Physics · Physics 2023-04-11 Kai Sum Chan , H. F. Chau

The use of laser guide stars in astronomical adaptive optics results in elongated Shack-Hartmann wavefront sensor image patterns. Image correlation techniques can be used to determine local wavefront slope by correlating each sub-aperture…

Instrumentation and Methods for Astrophysics · Physics 2014-03-05 Alastair Basden

We study a mid-order wavefront sensor (MOWFS) to address fine cophasing errors in exoplanet imaging with future large segmented aperture space telescopes. Observing Earth analogs around Sun-like stars requires contrasts down to $10^{-10}$…

Instrumentation and Methods for Astrophysics · Physics 2024-09-10 B. Buralli , M. N'Diaye , R. Pourcelot , M. Carbillet , E. H. Por , I. Laginja , L. Canas , S. Steiger , P. Petrone , M. M. Nguyen , B. Nickson , S. F. Redmond , A. Sahoo , L. Pueyo , M. D. Perrin , R. Soummer

Wavefront shaping techniques allow waves to be focused on a diffraction-limited target deep inside disordered media. To identify the target position, a guidestar is required that typically emits a frequency-shifted signal. Here we present a…

Applied Physics · Physics 2025-05-13 Antton Goïcoechea , Jakob Hüpfl , Stefan Rotter , François Sarrazin , Matthieu Davy

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

For sufficiently wide ranges of applied control signals (control voltages), MEMS and piezoelectric Deformable Mirrors (DMs), exhibit nonlinear behavior. The nonlinear behavior manifests itself in nonlinear actuator couplings, nonlinear…

Systems and Control · Electrical Eng. & Systems 2022-03-10 Aleksandar Haber

From the earth's crust to the human brain, remitted waves are used for sensing and imaging in a diverse range of diffusive media. Separating the source and detector increases the penetration depth of remitted light, yet rapidly decreases…

In laser gravitational waves detectors optical loss restricts sensitivity. We discuss polarization scattering as one more possible mechanism of optical losses. Circulated inside interferometer light is polarized and after reflection its…

Instrumentation and Methods for Astrophysics · Physics 2020-02-20 Sergey P. Vyatchanin

We propose a novel control approach that combines offline supervised learning to address the challenges posed by non-linear phase reconstruction using unmodulated pyramid wavefront sensors (P-WFS) and online reinforcement learning for…

Instrumentation and Methods for Astrophysics · Physics 2024-05-24 Bartomeu Pou , Jeffrey Smith , Eduardo Quinones , Mario Martin , Damien Gratadour

The reflection of an optical wave from a metal, arising from strong interactions between the optical electric field and the free carriers of the metal, is accompanied by a phase reversal of the reflected electric field. A far less common…

In this paper, we derive a new class of methods for the classic 2D phase unwrapping problem of recovering a phase function from its wrapped form. For this, we consider the wrapped phase as a wavefront aberration in an optical system, and…

Numerical Analysis · Mathematics 2025-03-14 Simon Hubmer , Victoria Laidlaw , Ronny Ramlau , Ekaterina Sherina , Bernadett Stadler

One of the greatest challenges in utilizing multimode optical fibers is mode-mixing and inter-modal interference, which scramble the information delivered by the fiber. A common approach for canceling these effects is to tailor the optical…

In planar metamaterial lenses, the focal point moves with the frequency. Here it is shown numerically that this movement can be controlled by properly engineering the dimensions of the metamaterial-based phase shifters that constitute the…

Optics · Physics 2013-03-01 W. J. Capecchi , N. Behdad , F. A. Volpe

Continuous wavefront sensing on future space telescopes allows relaxation of stability requirements while still allowing on-orbit diffraction-limited optical performance. We consider the suitability of phase retrieval to continuously…

Instrumentation and Methods for Astrophysics · Physics 2023-09-14 Hyukmo Kang , Kyle Van Gorkom , Jess Johnson , Ole Singlestad , Aaron Goldtooth , Daewook Kim , Ewan S. Douglas

Waveguide mirrors possess nano-structured surfaces which can potentially provide a significant reduction in thermal noise over conventional dielectric mirrors. To avoid introducing additional phase noise from motion of the mirror transverse…

Instrumentation and Methods for Astrophysics · Physics 2016-08-10 S. Leavey , B. W. Barr , A. S. Bell , E-B. Kley , N. Gordon , C. Gräf , S. Hild , S. H. Huttner , S. Kroker , J. Macarthur , C. Messenger , M. Pitkin , B. Sorazu , K. Strain , A. Tünnermann
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