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Related papers: Interferometric apodization by homothety -- II. Ex…

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This study is focused on the very high dynamic imaging field, specifically the direct observation of exoplanetary systems. The coronagraph is an essential technique for suppressing the star's light, making it possible to detect an exoplanet…

Instrumentation and Methods for Astrophysics · Physics 2023-07-12 Jamal Chafi , Youssef El Azhari , Ossama Azagrouze , Abdelhadi Jabiri , Zouhair Benkhaldoun , Abdelfatah Habib , Youssef Errazzouki

Phase-induced amplitude apodization (PIAA) coronagraphs are a promising technology for imaging exoplanets, with the potential to detect Earth-like planets around Sun-like stars. A PIAA system nominally consists of a pair of mirrors which…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 E. Cady

Phase-shifting interferometry is one of the optical measurement techniques that improves accuracy and resolution by incorporating a controlled phase shift into conventional optical interferometry. In this study, a four-step phase-shifting…

Applied Physics · Physics 2025-03-18 Eita Shoji , Anis Maddi , Guillaume Penelet , Tetsushi Biwa

The Phase-Induced Amplitude Apodization (PIAA) coronagraph is a high performance coronagraph concept able to work at small angular separation with little loss in throughput. We present results obtained with a laboratory PIAA system…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Olivier Guyon , Eugene Pluzhnik , Frantz Martinache , Julien Totems , Shinichiro Tanaka , Taro Matsuo , Celia Blain , Ruslan Belikov

Laser heterodyne interferometry plays a key role in the proof mass's monitor and control by measuring its multiple degrees of freedom motions in the Space Gravitational Wave Detection. Laboratory development of polarization-multiplexing…

Instrumentation and Methods for Astrophysics · Physics 2022-07-15 Xin Xu , Yidong Tan

The purpose of this paper is to present the results of a theoretical study pertaining to the feasibility of PIAA units using Deformable Mirrors. We begin by reviewing the general derivation of the design equations driving PIAA. We then show…

Instrumentation and Methods for Astrophysics · Physics 2011-11-23 Laurent Pueyo , N. Jeremy Kasdin , Alexis Carlotti , Robert Vanderbei

We introduce a new technique for imaging the polarized radio sky using interferometric data. The new approach, which we call Faraday synthesis, combines aperture and rotation measure synthesis imaging and deconvolution into a single…

Instrumentation and Methods for Astrophysics · Physics 2015-06-03 M. R. Bell , T. A. Enßlin

The specification of polishing requirements for the optics in coronagraphs dedicated to exo-planet detection requires careful and accurate optical modelling. Numerical representations of the propagation of aberrations through the system as…

Instrumentation and Methods for Astrophysics · Physics 2011-11-07 Laurent Pueyo , N. Jeremy Kasdin , Stuart Shaklan

Balanced homodyne interferometry is a well-known detection technique that allows for sensitive characterization of light fields. Conventionally a homodyne interferometer is operated by locking the relative phase of a reference beam to the…

Standard apodization methods suppress side lobes but increase FWHM, reducing lateral resolution. Grating lobes can interfere with the main lobe, introducing artifacts in ultrasound images. A simple mathematical apodization function is…

Medical Physics · Physics 2025-09-12 Dalton H Bermudez

Properly apodized pupils can deliver point spread functions (PSFs) free of Airy rings, and are suitable for high dynamical range imaging of extrasolar terrestrial planets (ETPs). To reach this goal, classical pupil apodization (CPA)…

Astrophysics · Physics 2007-05-23 E. A. Pluzhnik , O. Guyon , S. T. Ridgway , F. Martinache , R. A. Woodruff , C. Blain , R. Galicher

Two optical fiber Mach-Zehnder interferometers were constructed in an environment with a temperature stabilization of better than 1 mK per day. One interferometer with a length of 2 m optical fiber in each arm with the main direction of the…

Classical Physics · Physics 2015-05-14 Victor de Haan

We present the design, bench-top setup, and experimental results of a compact heterodyne interferometer that achieves picometer-level displacement sensitivities in air over frequencies above 100 mHz. The optical configuration with spatially…

Instrumentation and Detectors · Physics 2020-07-15 Ki-Nam Joo , Erin Clark , Yanqi Zhang , Jonathan D. Ellis , Felipe Guzman

Fourier ptychography (FP) is a powerful light-based synthetic aperture imaging technique that allows one to reconstruct a high-resolution, wide field-of-view image by computationally integrating a diverse collection of low-resolution,…

Image and Video Processing · Electrical Eng. & Systems 2025-07-21 Matthew A. Chan , Casey J. Pellizzari , Christopher A. Metzler

We present revised point-spread functions (PSFs) for the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). These PSFs provide a robust estimate of the light diffracted by the meshes holding the entrance and…

Solar and Stellar Astrophysics · Physics 2025-02-26 Stefan Hofmeister , Daniel Wolf Savin , Michael Hahn

This paper presents the results of a Fresnel Interferometric Array testbed. This new concept of imager involves diffraction focussing by a thin foil, in which many thousands of punched subapertures form a pattern related to a Fresnel zone…

Astrophysics · Physics 2008-08-07 Denis Serre , Laurent Koechlin , Paul Deba

We experimentally demonstrate optical Mach-Zehnder interferometer utilizing displaced Sagnac configuration to enhance its phase stability. The interferometer with footprint of 27x40 cm offers individually accessible paths and shows phase…

Optical interferometers increasingly use single-mode fibers as spatial filters to convert varying wavefront distortion into intensity fluctuations which can be monitored for accurate calibration of fringe amplitudes. Here I propose using an…

Astrophysics · Physics 2009-11-06 J. D. Monnier

We present a Bayesian approach to calculating the coefficients that convert the outputs of ALMA 183 GHz water-vapour radiometers into estimates of path fluctuations which can then be used to correct the observed interferometric…

Instrumentation and Methods for Astrophysics · Physics 2009-03-19 B. Nikolic

We demonstrate a simple and robust methodology for measuring and analyzing the polarization impedance appearing at interface between electrodes and ionic solutions, in the frequency range from 1 to $10^6$ Hz. The method assumes no…

Soft Condensed Matter · Physics 2009-09-15 Camelia Prodan , Corina Bot
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