English
Related papers

Related papers: Error analysis of moment-based modal wavefront sen…

200 papers

Precise alignment sensing and control are essential for maintaining the stability of laser interferometric gravitational-wave detectors. Conventional Wave Front Sensing technique (WFS), which relies on the beat between the carrier and…

General Relativity and Quantum Cosmology · Physics 2026-03-04 Chiaki Hirose , Kenta Tanaka , Osamu Miyakawa , Takafumi Ushiba

A novel approach to improving the performances of confocal scanning imaging is proposed. We experimentally demonstrate its feasibility using acoustic waves. It relies on a new way to encode spatial information using the temporal dimension.…

We demonstrate a wavefront sensor based on the compressive sensing, single-pixel camera. Using a high-resolution spatial light modulator (SLM) as a variable waveplate, we weakly couple an optical field's transverse-position and polarization…

Optics · Physics 2014-07-30 Gregory A. Howland , Daniel J. Lum , John C. Howell

The modulation transfer function (MTF) is widely used to characterise the performance of optical systems. Measuring it is costly and it is thus rarely available for a given lens specimen. Instead, MTFs based on simulations or, at best, MTFs…

Computer Vision and Pattern Recognition · Computer Science 2018-05-07 Matthias Bauer , Valentin Volchkov , Michael Hirsch , Bernhard Schölkopf

Modeling the optical point spread function (PSF) is particularly challenging for adaptive optics (AO)-assisted observations owing to the its complex shape and spatial variations. We aim to (i) exhaustively demonstrate the accuracy of a…

Instrumentation and Methods for Astrophysics · Physics 2020-11-25 Olivier Beltramo-Martin , Romain Fétick , Benoit Neichel , Thierry Fusco

Concatenated modal interferometers based multipoint sensing system for detection of instantaneous amplitude, frequency, and phase of mechanical vibrations is proposed and demonstrated. The sensor probes are fabricated using identical…

Instrumentation and Detectors · Physics 2021-05-17 Kalipada Chatterjee , Venugopal Arumuru , Dhananjay Patil , Rajan Jha

The dispersion surfaces of printed periodic structures in layered media are efficiently computed using a full-wave method based on the periodic Method of Moments (MoM). The geometry of the dispersion surface is estimated after mapping the…

Computational Physics · Physics 2023-09-27 Denis Tihon , Shambhu Nath Jha , Modeste Bodehou , Christophe Craeye

We present a new approach for spatiotemporal focusing through complex scattering media by wave front shaping. Using a nonlinear feedback signal to shape the incident pulsed wave front, we show that the limit of a spatiotemporal matched…

We propose an empirical method for identifying low damped modes and corresponding mode shapes using frequency measurements from a Wide Area Monitoring System. The method consists of two main steps: Firstly, Complex Principal Component…

Signal Processing · Electrical Eng. & Systems 2021-02-02 Hallvar Haugdal , Kjetil Uhlen

Context. Solar wavefront sensing has been a challenge for astrophysical instrumentalists, due to the low contrast between the Sun and the sky background compared to night-time observations, which limits the performance of adaptive optics…

A main science goal for the Large Synoptic Survey Telescope (LSST) is to measure the cosmic shear signal from weak lensing to extreme accuracy. One difficulty, however, is that with the short exposure time ($\simeq$15 seconds) proposed, the…

High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky…

Instrumentation and Methods for Astrophysics · Physics 2021-07-19 Steven P. Bos , Michael Bottom , Sam Ragland , Jacques-Robert Delorme , Sylvain Cetre , Laurent Pueyo

Here we present a laboratory analysis of the use of a 19-core photonic lantern (PL) in combination with neural network (NN) algorithms as an efficient focal plane wavefront sensor (FP-WFS) for adaptive optics (AO), measuring wavefront…

Optics · Physics 2023-11-06 Jin Wei , Barnaby Norris , Christopher Betters , Sergio Leon-Saval

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

Magnetic guiding fields in combination with energy dispersive semiconductor detectors have been employed already more than 50 years ago for in-beam internal conversion electron spectroscopy. Even then it was recognized that efficiency…

Instrumentation and Detectors · Physics 2015-03-25 H. Backe

The influence of low-spatial frequency errors of an optical component of an imaging system on the point spread function can be quantified using Zernike polynomials. High-spatial frequency errors cause strong scattering due to which the…

Optics · Physics 2026-04-03 Luuk Zonneveld , Paul Urbach , Aurèle Adam

Traditionally one defines the speed of a wave as a property of the medium. Recent studies in photonics have challenged this idea, indicating that spatial shaping of the optical wavefront has can alter the arrival time of single photons when…

The point-spread function (PSF) is a fundamental property of any astronomical instrument. In interferometers, differing array configurations combined with their $uv$ coverage, and various weighting schemes can produce an irregular but…

Instrumentation and Methods for Astrophysics · Physics 2023-10-20 Jack F. Radcliffe , R. J. Beswick , A. P. Thomson , A. Njeri , T. W. B. Muxlow

We investigate the impact of instrumental systematic errors on the potential of cosmic microwave background polarization experiments targeting primordial B-modes. To do so, we introduce spin-weighted Muller matrix-valued fields describing…

Astrophysics · Physics 2008-11-26 Daniel O'Dea , Anthony Challinor , Bradley R. Johnson

Several types of Wavefront Sensors (WFS) are nowadays available in the field of Adaptive Optics (AO). Generally speaking, their basic principle consists in measuring slopes or curvatures of Wavefront Errors (WFE) transmitted by a telescope,…

Optics · Physics 2011-05-17 Francois Henault
‹ Prev 1 4 5 6 7 8 10 Next ›