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Astronomers usually need the highest angular resolution possible, but the blurring effect of diffraction imposes a fundamental limit on the image quality from any single telescope. Interferometry allows light collected at widely-separated…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John D. Monnier , Ronald J. Allen

Diffractive/refractive optics, such as Phase Fresnel Lenses (PFL's), offer the potential to achieve excellent imaging performance in the x-ray and gamma-ray photon regimes. In principle, the angular resolution obtained with these devices…

A good knowledge of the angular diameters of stars used to calibrate the observables in stellar interferometry is fundamental. As the available precision for giant stars is worse than the required per cent level, we aim to improve the…

At present, the principal limitation on the resolution and contrast of astronomical imaging instruments comes from aberrations in the optical path, which may be imposed by the Earth's turbulent atmosphere or by variations in the alignment…

Instrumentation and Methods for Astrophysics · Physics 2015-10-23 Benjamin Pope , Peter Tuthill , Sasha Hinkley , Michael J. Ireland , Alexandra Greenbaum , Alexey Latyshev , John D. Monnier , Frantz Martinache

Fourier transform spectroscopy (FTS) has been widely used as an analytical tool for many applications in science and engineering. In this paper, we describe the operation principle and practical implementation of an FTS prototype. First,…

Instrumentation and Detectors · Physics 2023-02-02 Sohrab Sheikh-Sofla , Mohammad Neshat

We report the first use of Michelson interferometry on the Keck I telescope for diffraction-limited imaging in the near infrared JHK and L bands. By using an aperture mask located close to the f/25 secondary, the 10 m Keck primary mirror…

Astrophysics · Physics 2009-10-31 P. G. Tuthill , J. D. Monnier , W. C. Danchi , E. H. Wishnow , C. A. Haniff

In long-baseline interferometry, bandwidth smearing of an extended source occurs at finite bandwidth when its different components produce interference packets that only partially overlap. In this case, traditional model fitting or image…

Instrumentation and Methods for Astrophysics · Physics 2013-08-07 Régis Lachaume , Jean-Philippe Berger

We show star images obtained with a miniature ``densified pupil imaging interferometer'' also called a hyper-telescope. The formation of such images violates a ``golden rule of imaging interferometers'' which appeared to forbid the use of…

Astrophysics · Physics 2009-10-31 E. Pedretti , A. Labeyrie , L. Arnold , N. Thureau , O. Lardiere , A. Boccaletti , P. Riaud

Computer vision applications have heavily relied on the linear combination of Lambertian diffuse and microfacet specular reflection models for representing reflected radiance, which turns out to be physically incompatible and limited in…

Computer Vision and Pattern Recognition · Computer Science 2022-12-09 Tomoki Ichikawa , Yoshiki Fukao , Shohei Nobuhara , Ko Nishino

We study the sensitivities of space infrared interferometers. We formulate the signal-to-noise ratios of infrared images obtained by aperture synthesis in the presence of source shot noise, background shot noise and detector read noise. We…

Astrophysics · Physics 2009-10-31 Tadashi Nakajima , Hideo Matsuhara

Resolving high-contrast targets is a fundamental yet highly challenging task in astronomy. Using quantum estimation theory, we demonstrate that the ultimate limit for estimating the separation between two unequal-brightness thermal sources…

Instrumentation and Methods for Astrophysics · Physics 2025-09-17 Chenyu Hu , Ben Wang , Jiandong Zhang , Kunxu Wang , Huigen Liu , Jilin Zhou , Lijian Zhang

Visible-infrared object detection has gained sufficient attention due to its detection performance in low light, fog, and rain conditions. However, visible and infrared modalities captured by different sensors exist the information…

Computer Vision and Pattern Recognition · Computer Science 2025-11-17 Wencong Wu , Xiuwei Zhang , Hanlin Yin , Shun Dai , Hongxi Zhang , Yanning Zhang

The imaging sharpness of an X-ray telescope is chiefly determined by the optical quality of its focusing optics, which in turn mostly depends on the shape accuracy and the surface finishing of the grazing-incidence X-ray mirrors that…

Instrumentation and Methods for Astrophysics · Physics 2014-12-10 Lorenzo Raimondi , Daniele Spiga

We implement an estimator for determining the separation between two incoherent point sources. This estimator relies on image inversion interferometry and when used with the appropriate data analytics, it yields an estimate of the…

Optics · Physics 2016-05-31 Tang Zong Sheng , Kadir Durak , Alexander Ling

In this Letter we present a Fresnel lens fabricated on the end of an optical fiber. The lens is fabricated using nanoimprint lithography of a functional high refractive index material, which is suitable for mass production. The main…

We report development of a simple and affordable radio interferometer suitable as an educational laboratory experiment. With the increasing importance of interferometry in astronomy, the lack of educational interferometers is an obstacle to…

Instrumentation and Methods for Astrophysics · Physics 2016-04-20 Jin Koda , James Barrett , Tetsuo Hasegawa , Masahiko Hayashi , Gene Shafto , Jeff Slechta , Stanimir Metchev

Interference with atomic and molecular matter waves is a rich branch of atomic physics and quantum optics. It started with atom diffraction from crystal surfaces and the separated oscillatory fields technique used in atomic clocks. Atom…

Quantum Physics · Physics 2009-08-03 Alexander D. Cronin , Joerg Schmiedmayer , David E. Pritchard

Most telescope designs have a circular-shape aperture. We demonstrate that telescopes with an elongated pupil have better contrast, at lower separations, between a bright central star and a faint companion. We simulate images for an…

Instrumentation and Methods for Astrophysics · Physics 2019-07-24 Guy Nir , Barak Zackay , Eran O. Ofek

The application of precision interferometers is generally restricted to expensive and smooth high-quality surfaces. Here, we offer a route to ultimate miniaturization of interferometer by integrating beam splitter, reference mirror and…

Optics · Physics 2019-09-23 Pooja Munjal , Kamal P. Singh

Astrometric detection and mass determination of Earth-mass exoplanets requires sub-microarcsec accuracy, which is theoretically possible with an imaging space telescope using field stars as an astrometric reference. The measurement must…

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