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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

We propose and demonstrate a new phase retrieval method for imaging through random media. Although methods to recover the Fourier amplitude through random distortions are well established, recovery of the Fourier phase has been a more…

Optics · Physics 2021-05-14 Byungjae Hwang , Taeseong Woo , Cheolwoo Ahn , Jung-Hoon Park

Radio interferometers observe the Fourier space of the sky, at locations determined by the array geometry. Before a real space image is constructed by a Fourier transform, the data is weighted to improve the quality of reconstruction. Two…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Sarod Yatawatta

Long baseline optical interferometry and aperture synthesis using ground-based telescopes can enable unprecedented angular resolution astronomy in the optical domain. However, atmospheric turbulence leads to large, dynamic phase errors…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 Ross Cheriton , Siegfried Janz , Glen Herriot , Jean-Pierre Véran , Brent Carlson

Microwave, submillimetre-wave, and far-infrared phased arrays are of considerable importance for astronomy. We consider the behaviour imaging phased arrays and interferometric phased arrays from a functional perspective. It is shown that…

Astrophysics · Physics 2009-11-11 Stafford Withington , George Saklatvala , Michael P. Hobson

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

Using a linear optical elements and post-selection, we construct an entangled polarization state of three photons in the same spatial mode. This state is analogous to a ``photon-number path entangled state'' and can be used for…

Quantum Physics · Physics 2009-11-10 M. W. Mitchell , J. S. Lundeen , A. M. Steinberg

Fourier optics, the principle of using Fourier Transformation to understand the functionalities of optical elements, lies at the heart of modern optics, and has been widely applied to optical information processing, imaging, holography etc.…

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

Intensity interferometry removes the stringent requirements on mechanical precision and atmospheric corrections that plague all amplitude interferometry techniques at the cost of severely limited sensitivity. A new idea we recently…

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

A device based on a three-block Fresnel zone plate interferometer is proposed for hard X-ray phase-contrast imaging. The device combines a low requirement for the coherence of the initial radiation (the interferometer operates in the…

Instrumentation and Detectors · Physics 2021-04-22 L. A. Haroutunyan

We have developed an algorithm that constructs a model of a reconfigurable optical interferometer, independent of specific architectural constraints. The programming of unitary transformations on the interferometer's optical modes relies on…

Quantum Physics · Physics 2025-06-02 Sergei S. Kuzmin , Ivan V. Dyakonov , Stanislav S. Straupe

Phase-contrast imaging is an emerging technology that may increase the signal-difference-to-noise ratio in medical imaging. One of the most promising phase-contrast techniques is Talbot interferometry, which, combined with energy-sensitive…

We are developing the super broad band interferometer by applying the Fourier Transform Spectrometer(FTS) to aperture synthesis system in mm and sub-mm bands. We have constructed a compact system based on the Martin and Puplett type Fourier…

Astrophysics · Physics 2009-11-10 Izumi S. Ohta , Makoto Hattori , Hiroshi Matsuo

In this communication are presented some complements to a recent paper entitled "Simple Fourier optics formalism for high angular resolution systems and nulling interferometry", dealing with imaging and nulling capacities of a few types of…

Optics · Physics 2015-05-18 François Hénault

Fourier ptychography (FP), as a computational imaging method, is a powerful tool to improve imaging resolution. Camera-scanning Fourier ptychography extends the application of FP from micro to macro creatively. Due to the non-ideal scanning…

Image and Video Processing · Electrical Eng. & Systems 2022-06-08 Baiqi Cui , Shaohui Zhang , Yechao Wang , Yao Hu , Qun Hao

This paper addresses the problem of expressing a signal as a sum of frequency components (sinusoids) wherein each sinusoid may exhibit abrupt changes in its amplitude and/or phase. The Fourier transform of a narrow-band signal, with a…

Machine Learning · Computer Science 2013-02-27 Yin Ding , Ivan W. Selesnick

We report a novel microscopy platform, termed Multi-Aperture Fourier ptychographic microscopy (MA-FPM), capable of realizing gigapixel complex field images with large data acquisition bandwidths - in gigapixels per second. MA-FPM is a…

Optics · Physics 2020-10-14 Pavan Chandra Konda , Jonathan M. Taylor , Andrew R. Harvey

A Michelson-type interferometer with two-mode squeezed coherent state input is considered. Such an interferometer has a better phase sensitivity over the shot-noise limit by a factor of $e^{2r}$, where $r$ is the squeezing parameter [Phys.…

Quantum Physics · Physics 2023-03-03 Stav Haldar , Pratik J. Barge , Xiao-Qi Xiao , Hwang Lee

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…

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