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Active optics is defined as the control of the shape and the alignment of the components of an optical system at low temporal frequencies. For modern large telescopes with flexible monolithic or segmented primary mirrors and also flexible…

Astrophysics · Physics 2007-05-23 Lothar Noethe

We present an analytical derivation of the on-axis performance of Adaptive Optics systems using a given number of guide stars of arbitrary altitude, distributed at arbitrary angular positions in the sky. The expressions of the residual…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 E. Tatulli , A. N. Ramaprakash

A new high-order adaptive optics system is now being commissioned at the Lick Observatory Shane 3-meter telescope in California. This system uses a high return efficiency sodium beacon and a combination of low and high-order deformable…

Sub-wavelength diffractive optics meta-optics present a multi-scale optical system, where the behavior of constituent sub-wavelength scatterers, or meta-atoms, need to be modelled by full-wave electromagnetic simulations, whereas the whole…

Accurate and precise measurements of the Hubble constant are critical for testing our current standard cosmological model and revealing possibly new physics. With Hubble Space Telescope (HST) imaging, each strong gravitational lens system…

Adaptive optics (AO) is a technique to improve the resolution of ground-based telescopes by correcting, in real-time, optical aberrations due to atmospheric turbulence and the telescope itself. With the rise of Giant Segmented Mirror…

Angle-resolved photoemission spectroscopy with sub-micrometer spatial resolution ({\mu}-ARPES), has become a powerful tool for studying quantum materials. To achieve sub-micrometer or even nanometer-scale spatial resolution, it is important…

We present a beam steering system based on micro-electromechanical systems technology that features high speed steering of multiple laser beams over a broad wavelength range. By utilizing high speed micromirrors with a broadband metallic…

Optics · Physics 2015-05-13 Caleb Knoernschild , Changsoon Kim , Felix P. Lu , Jungsang Kim

Adaptive optics systems require a calibration procedure to operate, whether in closed loop or even more importantly in forward control. This calibration usually takes the form of an interaction matrix and is a measure of the response on the…

Instrumentation and Methods for Astrophysics · Physics 2021-01-15 Olivier Lai , Mark Chun , Ryan Dungee , Jessica Lu , Marcel Carbillet

Fluorescence Correlation Spectroscopy (FCS) yields measurement parameters (number of molecules, diffusion time) that characterize the concentration and kinetics of fluorescent molecules within a supposedly known observation volume. Absolute…

Biological Physics · Physics 2011-12-23 Charles Edouard Leroux , Irène Wang , Jacques Derouard , Antoine Delon

Delay and sum (DAS) is the most common beamforming algorithm in linear-array photoacoustic imaging (PAI) as a result of its simple implementation. However, it leads to a low resolution and high sidelobes. Delay multiply and sum (DMAS) was…

Signal Processing · Electrical Eng. & Systems 2018-02-23 Moein Mozaffarzadeh , Ali Mahloojifar , Mohammadreza Nasiriavanaki , Mahdi Orooji

ERIS is the new AO instrument for VLT-UT4 led by a Consortium of Max-Planck Institut fuer Extraterrestrische Physik, UK-ATC, ETH-Zurich, ESO and INAF. The ERIS AO system provides NGS mode to deliver high contrast correction and LGS mode to…

In the last few years, new Adaptive Optics [AO] techniques have emerged to answer new astronomical challenges: Ground-Layer AO [GLAO] and Multi-Conjugate AO [MCAO] to access a wider Field of View [FoV], Multi-Object AO [MOAO] for the…

Astrophysics · Physics 2009-11-11 B. Neichel , J-M. Conan , T. Fusco , E. Gendron , M. Puech , G. Rousset , F. Hammer

Adaptive optics (AO) systems and image reconstruction algorithms are indispensable tools when it comes to high-precision astrometry. In this paper, we analyze the potential of combining both techniques, i.e. by applying image reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-03-13 Felix Bosco , Jörg-Uwe Pott , Rainer Schödel

Wide Field Adaptive Optics (WFAO) systems are among the most sophisticated AO systems available today on large telescopes. The knowledge of the vertical spatio-temporal distribution of the wind speed (WS) and direction (WD) are fundamental…

Instrumentation and Methods for Astrophysics · Physics 2018-01-25 G. Sivo , A. Turchi , E. Masciadri , A. Guesalga , B. Neichel

We report a technique for encoding both amplitude and phase variations onto a laser beam using a single digital micro-mirror device (DMD). Using this technique, we generate Laguerre-Gaussian and vortex orbital-angular-momentum (OAM) modes,…

NFIRAOS, the Thirty Meter Telescope's first adaptive optics system is an order 60x60 Multi-Conjugate AO system with two deformable mirrors. Although most observing will use 6 laser guide stars, it also has an NGS-only mode. Uniquely,…

We present laboratory results of the closed-loop performance of the Magellan Adaptive Optics (AO) Adaptive Secondary Mirror (ASM), pyramid wavefront sensor (PWFS), and VisAO visible adaptive optics camera. The Magellan AO system is a…

Instrumentation and Methods for Astrophysics · Physics 2014-07-23 Derek Kopon , Laird M. Close , Jared Males , Victor Gasho , Katie Morzinski , Katherine Follette

Since 2014, the LBT's First Light Adaptive Optics (FLAO) system has also included a seldom used capability, known as Enhanced Seeing Mode (ESM), that can improve the angular resolution over a 4' x 4' field of view (FOV). In full AO…

Instrumentation and Methods for Astrophysics · Physics 2019-11-05 Barry Rothberg , Julian C. Christou , Douglas L. Miller , Dave Thompson , Gregory E. Taylor , Christian Veillet

Adaptive optics (AO) has revolutionized imaging in {fields} from astronomy to microscopy by correcting optical aberrations. In label-free microscopes, however, conventional AO faces limitations due to the absence of guidestar and the need…

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