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Deformable Mirrors (DMs) have wide applications ranging from astronomical imaging to laser communications and vision science. However, they often require bulky multi-channel cables for delivering high power to their drive actuators. A low…

Instrumentation and Methods for Astrophysics · Physics 2021-12-28 Amit Kumar Jha , Ewan S. Douglas , Meng Li , Corey Fucetola , Fiorenzo G. Omenetto

The ability of aerial robots to operate in the presence of failures is crucial in various applications that demand continuous operations, such as surveillance, monitoring, and inspection. In this paper, we propose a fault-tolerant control…

Robotics · Computer Science 2023-09-27 Jennifer Yeom , Guanrui Li , Giuseppe Loianno

The major sources causing deterioration of optical quality in extremely large optical telescopes are misadjustments of the mirrors, deformations of monolithic mirrors, and misalignments of segments in segmented mirrors. For active optics…

Optics · Physics 2009-11-10 L. Noethe

We describe an adaptive optics technique for two-photon microscopy in which the deformable mirror used for aberration compensation is positioned in a plane conjugate to the plane of the aberration. We demonstrate in a proof-of-principle…

Optics · Physics 2023-07-19 Hari P. Paudel , John Taranto , Jerome Mertz , Thomas Bifano

Next-generation large segmented mirror telescopes are expected to perform direct imaging and characterization of Earth-like rocky planets, which requires contrast limits of $10^{-7}$ to $10^{-8}$ at wavelengths from I to J band. One…

We present an adaptive lens which tunes its focal length with a glass membrane that is deformed by an integrated piezo bending actuator. A particular challenge in the fabrication of this type of actuator is the need to contact the…

Optics · Physics 2016-03-31 Moritz Stürmer , Matthias C. Wapler , Ulrike Wallrabe

We present the results obtained with an end-to-end simulator of an Extreme Adaptive Optics (XAO) system control loop. It is used to predict its on-sky performances and to optimise the AO loop algorithms. It was first used to validate a…

Instrumentation and Methods for Astrophysics · Physics 2023-01-10 Anthony Berdeu , Michel Tallon , Éric Thiébaut , Mary Angelie Alagao , Sitthichat Sukpholtham , Maud Langlois , Adithep Kawinkij , Puttiwat Kongkaew

This paper addresses the problem of designing LDPC decoders robust to transient errors introduced by a faulty hardware. We assume that the faulty hardware introduces errors during the message passing updates and we propose a general…

Information Theory · Computer Science 2016-11-17 Elsa Dupraz , David Declercq , Bane Vasic , Valentin Savin

The Thirty Meter Telescope will use a sophisticated adaptive optics system called NFIRAOS. This system utilizes two deformable mirrors conjugate to 0 km and 11.2 km to apply a Multi-Conjugate Adaptive Optics (MCAO) correction over a 2…

Instrumentation and Methods for Astrophysics · Physics 2024-10-17 Mojtaba Taheri , David Andersen , Jean-Pierre Veran , Olivier Lardière

We apply robust control technics to an adaptive optics system including a dynamic model of the deformable mirror. The dynamic model of the mirror is a modification of the usual plate equation. We propose also a state-space approach to model…

Analysis of PDEs · Mathematics 2009-11-13 Lucie Baudouin , Denis Arzelier , Christophe Prieur , Fabien Guignard

We demonstrate real-time wavefront correction in a high-energy high-average-power DiPOLE100/Bivoj laser using adaptive optics. A bimorph deformable mirror and Shack-Hartmann wavefront sensor reduced wavefront error tenfold and improved the…

The surface figure of x-ray mirrors can be improved by differential deposition of thin films. To achieve the required corrections, WSi2 layers of variable thickness were deposited through beam-defining apertures of different openings. The…

Optics · Physics 2025-06-03 Ch. Morawe , S. Labouré , F. Perrin , A. Vivo , R. Barrett

In this paper, static and dynamic behavior of an electro statically actuated torsional micro actuator is studied. The micro actuator is composed of a micro mirror and two torsional beams, which are excited with two electrodes. Unlike the…

Mesoscale and Nanoscale Physics · Physics 2018-05-03 Meysam T. Chorsi , Hamed Mobki

On certain extent the behavior of the Adaptive Optics correction for Extremely Large Telescope scales with diameter size. But in Ground Layer Adaptive Optics the combined effect of a Large Field of View and the large overlap of Guide Stars…

Instrumentation and Methods for Astrophysics · Physics 2009-11-19 Carmelo Arcidiacono , Roberto Ragazzoni

Diffraction limited resolution adaptive optics (AO) correction in visible wavelengths requires a high performance control. In this paper we investigate infinite impulse response filters that optimize the wavefront correction: we tested…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 G. Agapito , C. Arcidiacono , F. Quirós-Pacheco , A. Puglisi , S. Esposito

We are developing an adaptive secondary mirror (ASM) that uses a new actuator technology created by the Netherlands Organization for Applied Scientific Research (TNO). The TNO hybrid variable reluctance actuators have more than an order of…

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

Misalignment between the camera frame and the operator frame is commonly seen in a teleoperated system and usually degrades the operation performance. The effects of such misalignment have not been fully investigated for eye-in-hand systems…

Robotics · Computer Science 2024-01-30 Liao Wu , Fangwen Yu , Thanh Nho Do , Jiaole Wang

The availability and performance of laser-based adaptive optics (AO) systems are strongly dependent on the power and quality of the laser beam before being projected to the sky. Frequent and time-consuming alignment procedures are usually…

Instrumentation and Methods for Astrophysics · Physics 2014-05-23 Clémentine Béchet , Andrés Guesalaga , Benoit Neichel , Vincent Fesquet , Héctor González-Núñez , Sebastián Zúñiga , Pedro Escarate , Dani Guzman

Metasurfaces, the two-dimensional counterpart of metamaterials, have caught great attention thanks to their powerful control over electromagnetic waves. Recent times have seen the emergence of a variety of metasurfaces exhibiting not only…

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