English
Related papers

Related papers: Granularit\'e laser et interf\'erences de speckles

200 papers

Optical interference is not only a fundamental phenomenon that has enabled new theories of light to be derived but it has also been used in interferometry for the measurement of small displacements, refractive index changes and surface…

Optics · Physics 2021-10-28 Chen Yang , Zhi-Yuan Zhou , Yan Li , Shi-Kai Liu , Zheng Ge , Guang-Can Guo , Bao-Sen Shi

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

The speckle imaging is a photographic technique that resolves objects viewed through severely distorted media. The results are insensitive to the errors caused by apparent size of the isoplanatic patch and the telescope aberrations. In this…

Astrophysics · Physics 2007-05-23 S K Saha

Modern optical spectrographs and optical interferometers push the limits in the spectral and spatial regime, providing important new tools for the exploration of the universe. In this contribution I outline the complementary nature of…

Solar and Stellar Astrophysics · Physics 2015-06-18 Stefan Kraus

Speckle is a wave interference phenomenon that has been studied in various fields, including optics, hydrodynamics and acoustics. Speckle patterns contain spectral information of the interfering waves, and of the scattering medium that…

We propose methods to perform intensity interferometry of photons having two different wavelengths. Distinguishable particles typically cannot interfere with each other, but we overcome that obstacle by processing the particles via…

Quantum Physics · Physics 2019-05-01 Jordan Cotler , Frank Wilczek , Victoria Borish

We have presented the basic mathematical treatment of interferometry in the optical domain. Its applications in astronomical observations using both the single aperture, as well as the diluted apertures are described in detail. We have also…

Astrophysics · Physics 2007-05-23 S. K. Saha

Phase-sensitive coherent imaging exploits changes in the phases of backscattered light to observe tiny alterations of scattering structures or variations of the refractive index. But moving scatterers or a fluctuating refractive index…

Optical stellar interferometers have demonstrated milli-arcsecond resolution with few apertures spaced hundreds of meters apart. To obtain rich direct images, many apertures will be needed, for a better sampling of the incoming wavefront.…

Instrumentation and Methods for Astrophysics · Physics 2014-09-17 Arun Surya , Swapan K. Saha , Antoine Labeyrie

The displacement field of an object surface can be measured by using speckle interferometry. This technique is based on the phenomenon of laser speckle and consists in correlating speckle interferograms taken after and before the…

Applied Physics · Physics 2019-03-26 Andrés E. Dolinko , Gustavo E. Galizzi

Conventional ground-based optical telescopes, even those with large apertures, primarily observe stars, close binaries, and multiple systems as unresolved point sources through photometric measurements. Spectroscopy can identify multiple…

Instrumentation and Methods for Astrophysics · Physics 2025-12-10 Km Nitu Rai , Neelam Panwar , Jeewan C Pandey , T S Kumar , Subrata Sarangi , Prasenjit Saha

Infrared (IR) spectroscopy is an indispensable tool for many practical applications including material analysis and sensing. Existing IR spectroscopy techniques face challenges related to the inferior performance and the high cost of…

Optics · Physics 2017-03-13 Anna Paterova , Shaun Lung , Dmitry Kalashnikov , Leonid Krivitsky

Optical interferometric imaging enables astronomical observation at extremely high angular resolution. The necessary optical information for imaging, such as the optical path differences and visibilities, is easy to extract from fringes…

The resolution of a conventional telescope used to image visible-light synchrotron radiation is often limited by diffraction effects. To improve resolution, the double-slit interferometer method was developed at KEK and has since become…

Accelerator Physics · Physics 2019-11-13 Chunlei Li , Mark Boland , Jeff Corbett , Matan Grinberg , Toshiyuki Mitsuhashi , Yahong Xu , Wenjun Zhang

With the current revival of interest in astronomical intensity interferometry, it is interesting to revisit the associated theory, which was developed in the 1950s and 1960s. This paper argues that intensity interferometry can be understood…

Instrumentation and Methods for Astrophysics · Physics 2020-09-17 Prasenjit Saha

This paper will review the technical progress of interferometric infrared observing techniques from the first 2-element interferometer 25 years ago to the 3+ element arrays now coming into service. To date, only the Infrared Spatial…

Astrophysics · Physics 2007-05-23 John D. Monnier

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

Future large arrays of telescopes, used as intensity interferometers, can be used to image the surfaces of stars with unprecedented angular resolution. Fast-rotating, hot stars are particularly attractive targets for intensity…

Instrumentation and Methods for Astrophysics · Physics 2015-09-09 Paul D. Nunez , Armando Domiciano de Souza

The current status of the high spatial resolution imaging interferometry in optical astronomy is reviewed in the light of theoretical explanation, as well as of experimental constraints that exist in the present day technology. The basic…

Astrophysics · Physics 2007-05-23 S. K. Saha

Residual speckles due to aberrations arising from optical errors after the split between the wavefront sensor and the science camera path are the most significant barriers to imaging extrasolar planets. While speckles can be suppressed…

Instrumentation and Methods for Astrophysics · Physics 2016-10-12 Michael Bottom , J. Kent Wallace , Randall D. Bartos , J. Chris Shelton , Eugene Serabyn
‹ Prev 1 2 3 10 Next ›