English
Related papers

Related papers: Visibility retrieval in Michelson wide-field stell…

200 papers

Atmospheric turbulence and precise measurement of the astrometric baseline vector between any two telescopes are two major challenges in implementing phase referenced interferometric astrometry and imaging. They limit the performance of a…

Instrumentation and Methods for Astrophysics · Physics 2018-03-14 N. Anugu , A. Amorim , P. Gordo , F. Eisenhauer , O. Pfuhl , M. Haug , E. Wiezorrek , J. Lima , G. Perrin , W. Brandner , C. Straubmeier , J. -B. Le Bouquin , P. J. V Garcia

We present MIRReS, a novel two-stage inverse rendering framework that jointly reconstructs and optimizes the explicit geometry, material, and lighting from multi-view images. Unlike previous methods that rely on implicit irradiance fields…

Computer Vision and Pattern Recognition · Computer Science 2025-02-28 Yuxin Dai , Qi Wang , Jingsen Zhu , Dianbing Xi , Yuchi Huo , Chen Qian , Ying He

Camera arrays provide spatial and angular information within a single snapshot. With refocusing methods, focal planes can be altered after exposure. In this letter, we propose a light field refocusing method to improve the imaging quality…

Image and Video Processing · Electrical Eng. & Systems 2021-08-29 Yingqian Wang , Jungang Yang , Yulan Guo , Chao Xiao , Wei An

(Abridged) In the first part of this thesis, a general methodology for applying image deconvolution to wide-field CCD imagery. Results show that wavelet-based deconvolution can increase limiting magnitude up to 0.6 mag and improve limiting…

Astrophysics · Physics 2007-05-23 O. Fors

Optical reflection microscopy is one of the main imaging tools to visualize graphene microstructures. Here is reported a novel method that employs refractive index optimization in an optical reflection microscope, which greatly improves the…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 H. Gonçalves , L. Alves , C. Moura , M. Belsley , T. Stauber , P. Schellenberg

The conventional approach to high-precision narrow-angle astrometry using a long baseline interferometer is to directly measure the fringe packet separation of a target and a nearby reference star. This is done by means of a technique known…

Instrumentation and Methods for Astrophysics · Physics 2014-08-25 Y. Kok , M. J. Ireland , A. C. Rizzuto , P. G. Tuthill , J. G. Robertson , B. A. Warrington , W. J. Tango

Pupil-mapping is a technique whereby a uniformly-illuminated input pupil, such as from starlight, can be mapped into a non-uniformly illuminated exit pupil, such that the image formed from this pupil will have suppressed sidelobes, many…

Astrophysics · Physics 2009-11-13 R. J. Vanderbei

Staircase is one of the most common structures in artificial scenes. However, it is difficult for humanoid robots and people with lower limb disabilities or visual impairment to cross the scene without the help of sensors and intelligent…

Robotics · Computer Science 2025-08-29 Weifeng Kong , Zhiying Tan

Sample-induced aberrations and optical imperfections limit the resolution of fluorescence microscopy. Phase diversity is a powerful technique that leverages complementary phase information in sequentially acquired images with deliberately…

Stellar amplitude interferometry is limited by the need to have optical distances fixed and known to a fraction of the wavelength. We suggest reviving intensity interferometry, which requires hardware which is many orders of magnitude less…

Astrophysics · Physics 2009-11-11 Aviv Ofir , Erez N. Ribak

In stellar interferometry, image quality improves significantly with the inclusion of more telescopes and the use of phase closure. We demonstrate, using first coherent and then partially coherent white light, a compact and efficient…

Astrophysics · Physics 2009-11-13 E. N. Ribak , M. Gai , D. Loreggia , S. G. Lipson

We present 36 observations of 17 visual binaries of moderate separation (range from 0.15'' to 0.79'') made with the 50 cm Cassegrain telescope of the Jagiellonian University in Cracow. The speckle interferometry technique was combined with…

Astrophysics · Physics 2009-11-11 Artur Rutkowski , Waclaw Waniak

Mesh refinement is a fundamental step for accurate Multi-View Stereo. It modifies the geometry of an initial manifold mesh to minimize the photometric error induced in a set of camera pairs. This initial mesh is usually the output of…

Computer Vision and Pattern Recognition · Computer Science 2020-12-02 Andrea Romanoni , Matteo Matteucci

We report on the active stabilization of a Michelson interferometer at an arbitrary phase angle with a precision better than one degree at $\lambda = 632.8$ nm, which corresponds to an optical path difference between the two arms of less…

Optics · Physics 2015-06-18 Davide Grassani , Matteo Galli , Daniele Bajoni

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

The advent of large aperture arrays, such as the currently under construction Square Kilometer Array (SKA), allows for observing the universe in the radio-spectrum at unprecedented resolution and sensitivity. However, these telescopes…

Instrumentation and Methods for Astrophysics · Physics 2024-12-04 S. Wang , S. Prunet , S. Mignot , A. Ferrari

Since the 1970s, much of traditional interferometric imaging has been built around variations of the CLEAN algorithm, in both terminology, methodology, and algorithm development. Recent developments in applying new algorithms from convex…

Instrumentation and Methods for Astrophysics · Physics 2020-09-29 Luke Pratley , Melanie Johnston-Hollitt , Jason D. McEwen

Context: In recent years, stellar intensity interferometry has seen renewed interest from the astronomical community because it can be efficiently applied to Cherenkov telescope arrays. Aims: We have investigated the accuracy that can be…

Instrumentation and Methods for Astrophysics · Physics 2022-10-05 Michele Fiori , Giampiero Naletto , Luca Zampieri , Irene Jiménez Martínez , Carolin Wunderlich

Imaging specimens over large scales and with a sub-micron resolution is instrumental to biomedical research. Yet, the number of pixels to form such an image usually exceeds the number of pixels provided by conventional cameras. While most…

Instrumentation and Detectors · Physics 2019-12-03 Gaelle Recher , Pierre Nassoy , Amaury Badon

In this paper, we describe the principle of a multi-aperture interferometer that uses a phase-shifting technique and is suitable for quick, snapshot imaging of astrophysical objects at extreme angular resolution through Fourier inversion. A…

Optics · Physics 2015-05-28 Francois Henault