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X-ray interferometry is an emerging imaging modality with a wide variety of potential clinical applications, including lung and breast imaging, as well as in non-destructive testing, such as additive manufacturing and porosimetry. A grating…

Speckle is an intrinsic pattern in optical coherence tomography (OCT) that obscures fine image features and degrades effective resolution. In this study, we propose a numerical speckle reduction method based on the dispersed scatterer model…

A method for performing nonlocal interferometry using phase-entangled macroscopic coherent states is described. The required entanglement can be generated using weak nonlinearities while Bell's inequality can be violated using single…

Quantum Physics · Physics 2015-06-05 B. T. Kirby , J. D. Franson

Calibration of radio interferometric observations becomes increasingly difficult towards lower frequencies. Below ~300 MHz, spatially variant refractions and propagation delays of radio waves traveling through the ionosphere cause phase…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 H. T. Intema , S. van der Tol , W. D. Cotton , A. S. Cohen , I. M. van Bemmel , H. J. A. Rottgering

Here, we present a concept based on the realization that a complex medium can be used as a simple interferometer. Changes in the wavefront of an incident coherent beam can be retrieved by analyzing changes in speckle patterns when the beam…

Optics · Physics 2016-10-07 KyungDuk Kim , HyeonSeung Yu , KyeoReh Lee , YongKeun Park

We theoretically analyze the phase sensitivity of the Induced-Coherence (Mandel-Type) Interferometer, including the case where the sensitivity is "boosted" into the bright input regime with coherent-light seeding. We find scaling which…

Quantum Physics · Physics 2021-05-26 Nathaniel R. Miller , Sven Ramelow , William N. Plick

Optical diffraction tomography is an indispensable tool for studying objects in three-dimensions due to its ability to accurately reconstruct scattering objects. Until now this technique has been limited to coherent light because spatial…

A new method recovers the phase difference of interfering wavefronts from a pattern of interference fringes, avoiding the phase discontinuity problem. The method relies on the numerical solution of one-dimensional first-order ordinary…

Optics · Physics 2024-08-01 V. Berejnov , B. Y. Rubinstein

We follow the trajectories of phase singularities at nulls of intensity in the speckle pattern of waves transmitted through random media as the frequency of the incident radiation is scanned in microwave experiments and numerical…

Disordered Systems and Neural Networks · Physics 2015-06-19 Xiaojun Cheng , Yitzchak Lockerman , Azriel Z. Genack

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

A new method recovers phase difference of interfering wavefronts from a pattern of interference fringes, avoiding discontinuity problem. The continuous phase is a solution of the first order differential equation of the interferogram…

Data Analysis, Statistics and Probability · Physics 2024-04-24 V. Berejnov , B. Y. Rubinstein

We report a proof-of-concept demonstration of a tunable infrared (IR) optical coherence tomography (OCT) technique with detection of only visible range photons. Our method is based on the nonclassical interference of frequency correlated…

Quantum Physics · Physics 2018-04-09 Anna V. Paterova , Hongzhi Yang , Chengwu An , Dmitry A. Kalashnikov , Leonid A. Krivitsky

Interferometers measure a wide variety of dynamic processes by converting a phase change into an intensity change. Nonlinear interferometers, making use of nonlinear media in lieu of beamsplitters, promise substantial improvement in the…

Quantum Physics · Physics 2016-11-16 Joseph M. Lukens , Nicholas A. Peters , Raphael C. Pooser

Some types of medical and topographic imaging device produce images in which the pixel values are "phase-wrapped", i.e. measured modulus a known scalar. Phase unwrapping can be viewed as the problem of inferring the number of shifts between…

Computer Vision and Pattern Recognition · Computer Science 2013-01-14 Kannan Achan , Brendan J. Frey , Ralf Koetter

Optical spectroscopy is a fundamental tool in numerous areas of science and technology. Much effort has focused on miniaturizing spectrometers, but thus far at the cost of high spectral resolution and broad operating range. Here, we…

The optical elements comprised of sub-diffractive light scatterers, or metasurfaces, hold a promise to reduce the footprint and unfold new functionalities of optical devices. A particular interest is focused on metasurfaces for manipulation…

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

High-precision surface roughness estimation plays an important role in many applications. However, the classical estimating methods are limited by shot noise and only can achieve the precision of 0.1 nm with white light interferometer.…

Optics · Physics 2022-03-01 Hui-Chao Qu , Ya Xiao , Xin-Hong Han , Shan-Chuan Dong , Yong-Jian Gu

For the optical testing of a large mirror with a long radius of curvature, it is generally necessary to use a single-shot phase-shifting interferometer to take several measurements because the influence of air turbulence on air…

Image and Video Processing · Electrical Eng. & Systems 2020-05-26 Ohgan Kim , Bong Ju Lee , Yun-Woo Lee , Ho-Soon Yang

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