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Interest in pupil-remapping interferometry, in which a single telescope pupil is fragmented and recombined using fiber optic technologies, has been growing among a number of groups. As a logical extrapolation from several highly successful…

In this paper are reviewed various designs of advanced, multi-aperture optical systems dedicated to high angular resolution imaging or to the detection of exo-planets by nulling interferometry. A simple Fourier optics formalism applicable…

Optics · Physics 2016-01-20 Francois Henault

Traditional phase-shifting interferometry technique cannot be used to measure time-varying phase distributions. But single shot techniques could resolve the problem. Many efforts have been made on the phase retrieval methods from a single…

Instrumentation and Detectors · Physics 2020-03-31 Lifa Hu , Wen Shena , Wenchao Ma , Dongting Hu , Xinyu Liu

(Abridged) We consider the scientific case for a large aperture (10-12m class) optical spectroscopic survey telescope with a field of view comparable to that of LSST. Such a facility could enable transformational progress in several areas…

Instrumentation and Methods for Astrophysics · Physics 2017-01-10 Richard S. Ellis , Joss Bland-Hawthorn , Malcolm Bremer , Jarle Brinchmann , Luigi Guzzo , Johan Richard , Hans-Walter Rix , Eline Tolstoy , Darach Watson

Interferometers are widely used in imaging technologies to achieve enhanced spatial resolution, but require that the incoming photons be indistinguishable. In previous work, we built and analyzed color erasure detectors which expand the…

We present SPIFFI, the integral field spectrometer for the VLT. This instrument allows simultaneous observation of infrared spectra in more than 1000 image points of a two dimensional field. With its set of four gratings and a pixel scale…

Astrophysics · Physics 2015-06-24 F. Eisenhauer , M. Tecza , S. Mengel , N. Thatte , C. Roehrle , K. Bickert , J. Schreiber

New lensless diffractive X-ray technic for micro-scale imaging of biological tissue is based on quantitative phase retrieval schemes. By incorporating refraction, this method yields improved contrast compared to purely absorption-based…

Numerical Analysis · Mathematics 2018-03-28 Victor Palamodov

We propose a new approach, based on the Hanbury Brown and Twiss intensity interferometry, to transform a Cherenkov telescope to its equivalent optical telescope. We show that, based on the use of photonics components borrowed from…

Instrumentation and Methods for Astrophysics · Physics 2021-05-26 Pierre-Marie Gori , Farrokh Vakili , Jean-Pierre Rivet , William Guerin , Mathilde Hugbart , Andrea Chiavassa , Adrien Vakili , Robin Kaiser , Guillaume Labeyrie

Millimetre-VLBI is an important tool in AGN astrophysics, but it is limited by short atmospheric coherence times and poor receiver and antenna performance. We demonstrate a new kind of phase referencing for the VLBA, enabling us to increase…

Astrophysics · Physics 2007-05-23 E. Middelberg , A. L. Roy , R. C. Walker , H. Falcke , T. P. Krichbaum

Accurate weak-lensing analysis requires not only accurate measurement of galaxy shapes but also precise and unbiased measurement of galaxy redshifts. The photometric redshift technique appears as the only possibility to determine the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 S. Jouvel , J-P. Kneib , G. Bernstein , O. Ilbert , P. Jelinsky , B. Milliard , A. Ealet , C. Schimd , T. Dahlen , S. Arnouts

Limited-angle computed tomography (LACT) reconstruction is an inverse problem with severe ill-posedness arising from missing projection angles, and it is difficult to restore high-precision images without sufficient prior knowledge. In…

Image and Video Processing · Electrical Eng. & Systems 2026-03-06 Hinako Isogai , Naruki Murahashi , Mitsuhiro Nakamura , Megumi Nakao

We present computer simulations of interferometric imaging with the VLT interferometer and the AMBER instrument. These simulations include both the astrophysical modelling of a stellar object by radiative transfer calculations and the…

Astrophysics · Physics 2015-06-24 T. Bloecker , K. -H. Hofmann , F. Przygodda , G. Weigelt

Many undergraduate radio astronomy courses are unable to give a detailed treatment of aperture synthesis due to time constraints and limited math backgrounds of students. We have taken a laboratory-based approach to teaching radio…

Instrumentation and Methods for Astrophysics · Physics 2019-02-13 J. M. Marr , A. E. E. Rogers , V. L. Fish , F. P. Wilkin , M. B. Arndt , G. Holodak , K. Durkota

We summarise the mathematical foundation of the holographic method of measuring the reflector profile of an antenna or radio telescope. In particular, we treat the case, where the signal source is located at a finite distance from the…

Astrophysics · Physics 2016-11-18 J. W. M. Baars , R. Lucas , J. G. Mangum , J. A. Lopez-Perez

Camera calibration is an essential process in photogrammetry, serving as a crucial link between the 2D image coordinate system and the 3D world coordinate system. However, when observations are conducted through refractive interfaces, the…

This paper is the third part of a trilogy dealing with the principles, performance and limitations of what I named "Telescope-Interferometers" (TIs). The basic idea consists in transforming one telescope into a Wavefront Error (WFE) sensing…

Optics · Physics 2011-05-17 Francois Henault

Sub milli-arcsecond imaging in the visible band will provide a new perspective in stellar astrophysics. Even though stellar intensity interferometry was abandoned more than 40 years ago, it is capable of imaging and thus accomplishing more…

Instrumentation and Methods for Astrophysics · Physics 2010-09-29 Paul D. Nunez , Stephan LeBohec , David Kieda , Richard Holmes , Hannes Jensen , Dainis Dravins

Quadriwave lateral shearing interferometry (QLSI) is a quantitative phase imaging technique based on the use of a diffraction grating placed in front of a camera. This grating creates a wire-mesh-like image, called an interferogram, that is…

Optics · Physics 2022-03-15 Guillaume Baffou

The Fluorescence detector Array of Single-pixel Telescopes (FAST) is one of several proposed designs for a next-generation cosmic-ray detector. Such detectors will require enormous collecting areas whilst also needing to remain…