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Related papers: Polarization dOTF: on-sky focal plane wavefront se…

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Optical imperfections, misalignments, aberrations, and even dust can significantly limit sensitivity in high-contrast imaging systems such as coronagraphs. An upstream deformable mirror (DM) in the pupil can be used to correct or compensate…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Johanan L. Codona , Matthew Kenworthy

We present an experimental test of the use of stress engineered optics incorporated into a Shack-Hartmann wavefront sensor in such a way that the shape of the point spread function (PSF) provides polarization information while the…

Instrumentation and Detectors · Physics 2026-03-17 David E. Spiecker , Thomas G. Brown

The basic principle of astronomical interferometry is to derive the angular distribution of radiation in the sky from the Fourier transform of the electric field on the ground. What is so special about the Fourier transform? Nothing, it…

Instrumentation and Methods for Astrophysics · Physics 2015-01-30 Brian C. Lacki

The space-variant wavefront reconstruction problem inherently exists in deep tissue imaging. In this paper,we propose a framework of Shack-Hartmann wavefront space-variant sensing with extended source illumination. The space-variant…

Real-time seeing and outer scale estimation at the location of the focus of a telescope is fundamental for the adaptive optics systems dimensioning and performance prediction, as well as for the operational aspects of instruments. This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Patrice Martinez

Faraday tomography allows us to map diffuse polarized synchrotron emission from our Galaxy and use it to interpret the magnetic field in the interstellar medium (ISM). We have applied Faraday tomography to 60 observations from the LOFAR…

Low-light remote sensing images generally feature high resolution and high spatial complexity, with continuously distributed surface features in space. This continuity in scenes leads to extensive long-range correlations in spatial domains…

Computer Vision and Pattern Recognition · Computer Science 2024-09-09 Zishu Yao , Guodong Fan , Jinfu Fan , Min Gan , C. L. Philip Chen

The final performance of current and future instruments dedicated to exoplanet detection and characterization (such as SPHERE on the European Very Large Telescope, GPI on Gemini North, or future instruments on Extremely Large Telescopes) is…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 B. Paul , L. M. Mugnier , J. -F. Sauvage

By multiplexing information symbols in the delay-Doppler (DD) domain, orthogonal time frequency space (OTFS) is a promising candidate for future wireless communication in high-mobility scenarios. In addition to the superior communication…

Signal Processing · Electrical Eng. & Systems 2023-06-21 Kecheng Zhang , Zhongjie Li , Weijie Yuan , Yunlong Cai , Feifei Gao

Gratings and holograms are patterned surfaces that tailor optical signals by diffraction. Despite their long history, variants with remarkable functionalities continue to be discovered. Further advances could exploit Fourier optics, which…

We present a novel local-based face verification system whose components are analogous to those of biological systems. In the proposed system, after global registration and normalization, three eye regions are converted from the spatial to…

Computer Vision and Pattern Recognition · Computer Science 2007-05-23 Yossi Zana , Roberto M. Cesar-Jr , Rogerio S. Feris , Matthew Turk

We propose a focal-plane wavefront sensor (FPWFS) based on a short multimode fiber (MMF) capable of operating under moderately broadband illumination. By coupling the aberrated focal-plane field into an MMF of length <1 cm, we preserve…

Instrumentation and Methods for Astrophysics · Physics 2026-03-13 Auxiliadora Padrón-Brito , Natalia Arteaga-Marrero , Ian Cunnyngham , Jeff Kuhn

By switching fluorophores on and off in either a deterministic or a stochastic manner, superresolution microscopy has enabled the imaging of biological structures at resolutions well beyond the diffraction limit. Superresolution optical…

Time-of-flight (TOF) cameras are sensors that can measure the depths of scene-points, by illuminating the scene with a controlled laser or LED source, and then analyzing the reflected light. In this paper, we will first describe the…

Computer Vision and Pattern Recognition · Computer Science 2020-12-15 Radu Horaud , Miles Hansard , Georgios Evangelidis , Clement Menier

Ultra-reliable wireless communication links require the utilization of all diversity sources of a wireless communication channel. Hadani et al. propose a two dimensional discrete symplectic Fourier transform (DSFT) as orthogonal pre-coder…

Information Theory · Computer Science 2019-07-24 Thomas Zemen , Markus Hofer , David Loeschenbrand , Christoph Pacher

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

In this paper, we address the task of aberration-aware depth-from-defocus (DfD), which takes account of spatially variant point spread functions (PSFs) of a real camera. To effectively obtain the spatially variant PSFs of a real camera…

Computer Vision and Pattern Recognition · Computer Science 2024-02-29 Zhuofeng Wu , Yusuke Monno , Masatoshi Okutomi

We prove that it is impossible to distinguish two spatially coinciding fluorescent molecules from a single rotating molecule using polarization-sensitive imaging, even if one modulates the polarization of the illumination or the detection…

Optics · Physics 2025-03-11 Yiyang Chen , Yuanxin Qiu , Matthew D. Lew

In this paper we introduce a new 2D modulation technique called OTFS (Orthogonal Time Frequency & Space) that transforms information carried in the Delay-Doppler coordinate system to the familiar time-frequency domain utilized by…

Information Theory · Computer Science 2016-08-11 Anton Monk , Ronny Hadani , Michail Tsatsanis , Shlomo Rakib

The WALOP-South instrument will be mounted on the 1 m SAAO telescope in South Africa as part of the PASIPHAE program to carry out a linear imaging polarization survey of the Galactic polar regions in the optical band. Designed to achieve…