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Concept

Astronomical seeing

Related publications (15)

Validation of short-pulse reflectometry turbulence measurements with a synthetic diagnostic

Stefano Coda, Stephan Brunner, Oleg Krutkin, Samuele Mazzi, Umesh Kumar, Mackenzie Peter-Fulford Van Rossem

Experimental measurements of the turbulence amplitude utilizing a short pulse reflectometry method are presented. Two discharges with shaped plasma possessing opposite signs of triangularity are considered and a higher turbulence amplitude is found in the ...

IOP Publishing Ltd2024

Direct Data-Driven Vibration Control for Adaptive Optics

Alireza Karimi, Vaibhav Gupta

Adaptive optics (AO) systems are used in ground- based telescopes to improve image resolutions, especially for long-exposure photography, by compensating for the effects of atmospheric turbulence and internal vibrations. Most current AO systems are based o ...

2023

Circularly Polarized Transmitarray Antenna for CubeSat Intersatellite Links in K-Band

Anja Skrivervik, Miroslav Veljovic

A circularly polarized transmitarray antenna based on aperture-coupled patches is presented for CubeSat intersatellite-link applications in K-band. The concept of aperture coupling simplifies the design of transmitarray elements, as it omits the need for m ...

2020

Low-dimensional data embedding for scalable astronomical imaging in the SKA telescope era

Vijay Kartik

Astronomy is one of the oldest sciences known to humanity. We have been studying celestial objects for millennia, and continue to peer deeper into space in our thirst for knowledge about our origins and the universe that surrounds us. Radio astronomy -- ob ...

EPFL2018

Plasmonic Nanohole Arrays on Hybrid Substrate For Highly Sensitive Label-Free Biosensing

A biosensor device including a metal layer, a transparent substrate layer, and a dielectric layer, wherein the metal layer includes a plurality of sub-wavelength apertures, and wherein the dielectric layer is located between the metal layer and the transpa ...

2017

Binary zero-order diffractive and anti-reflective optical elements in silicon for the mid-infrared

Hans Peter Herzig, Grégoire Maxime Smolik

We propose a novel method for the design of binary 2-level diffractive optical elements that provide an efficient diffractive function while reducing the reflectivity of a high-index interface. The structure can be fabricated with a single patterning step ...

Optical Society of America2017

Design of a Switching Controller for Adaptive Disturbance Attenuation with Guaranteed Stability

Alireza Karimi

In this paper, a new algorithm is proposed for the design of a family of controllers to be used within an adaptive switching control scheme. The resulting switching controller is able to attenuate the effects of disturbances having uncertain and possibly t ...

2015

Volume refractometry of liquids using stable optofluidic Fabry-Perot resonator with curved surfaces

This work reports a simple, miniaturized optical sensing module for liquid refractometry. It is based on a stable Fabry-Perot resonator consisting of two silicon cylindrical mirrors with a cylindrical lens in the core. The lens is formed by a capillary tub ...

Spie-Int Soc Optical Engineering2015

Image Analysis For Cosmology: Results From The Great10 Star Challenge

Frédéric Courbin, Georges Meylan, Marc Gentile

We present the results from the first public blind point-spread function (PSF) reconstruction challenge, the GRavitational lEnsing Accuracy Testing 2010 (GREAT10) Star Challenge. Reconstruction of a spatially varying PSF, sparsely sampled by stars, at non- ...

University of Chicago Press2013

Exploring Neural Cell Dynamics with Digital Holographic Microscopy

Pierre Magistretti, Pierre Marquet, Christian Depeursinge

In this review, we summarize how the new concept of digital optics applied to the field of holographic microscopy has allowed the development of a reliable and flexible digital holographic quantitative phase microscopy (DH-QPM) technique at the nanoscale p ...

Annual Reviews2013

The application of Compressed Sensing Techniques in Radio Astronomy

Yves Wiaux

Radio interferometry probes astrophysical signals through incomplete and noisy Fourier measurements. The optimal reconstruction of these signals is an important topic not only for current astronomical imaging but also that of the next generation of radio t ...

IEEE2011

Gravitational Lensing Accuracy Testing 2010 (Great10) Challenge Handbook

Frédéric Courbin, Anaïs Marie Rassat, Matthias Bethge, Marc Gentile, Guldariya Nurbaeva

GRavitational lEnsing Accuracy Testing 2010 (GREAT10) is a public image analysis challenge aimed at the development of algorithms to analyze astronomical images. Specifically, the challenge is to measure varying image distortions in the presence of a varia ...

2011

Digital holographic reflectometry

Christian Depeursinge, Jonas Kühn, Tristan Colomb, Nicolas Pavillon, Ahmet Ata Akatay

Digital holographic microscopy (DHM) is an interferometric technique that allows real-time imaging of the entire complex optical wavefront (amplitude and phase) reflected by or transmitted through a sample. To our knowledge, only the quantitative phase is ...

2010

Amplitude point spread function measurement of high NA microscope objectives by digital holographic microscopy

Pierre Marquet, Christian Depeursinge, Tristan Colomb, Florian Charrière, Mihaela Marian

We present here a three-dimensional evaluation of the amplitude point-spread function (APSF) of a microscope objective (MO), based on a single holographic acquisition of its pupil wavefront. The aberration function is extracted from this pupil measurements ...

2007

Confining the sampling volume for Fluorescence Correlation Spectroscopy using a sub-wavelength sized aperture

Olivier Martin, Theo Lasser, Patrik Willi Hoffmann, Marcel Leutenegger, Alexandre Perentes

For the observation of single molecule dynamics with fluorescence fluctuation spectroscopy (FFS) very low fluorophore concentrations are necessary. For in vitro measurements, this requirement is easy to fulfill. In biology however, micromolar concentration ...

2006