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Combining large segmented space telescopes, coronagraphy and wavefront control methods is a promising solution to produce a dark hole (DH) region in the coronagraphic image of an observed star and study planetary companions. The thermal and…

Directly observing exoplanets with coronagraphs is impeded by the presence of speckles from aberrations in the optical path, which can be mitigated in hardware with wavefront control as well as in post-processing. This work explores using…

Instrumentation and Methods for Astrophysics · Physics 2025-04-03 Yinzi Xin , Laurent Pueyo , Romain Laugier , Leonid Pogorelyuk , Ewan S. Douglas , Benjamin J. S. Pope , Kerri L. Cahoy

Time-resolved atom interferometry, as employed in applications such as gravitational wave detection and searches for ultra-light dark matter, requires precise control over systematic effects. In this work, we investigate phase noise arising…

Atomic Physics · Physics 2025-11-25 Noam Mouelle , Jeremiah Mitchell , Valerie Gibson , Ulrich Schneider

This article describes the implementation of a focal plane based wavefront control loop on the high-contrast imaging instrument SCExAO (Subaru Coronagraphic Extreme Adaptive Optics). The sensor relies on the Fourier analysis of conventional…

Instrumentation and Methods for Astrophysics · Physics 2016-09-07 Frantz Martinache , Nemanja Jovanovic , Olivier Guyon

We present a multisensor fusion framework for the onboard real-time navigation of a quadrotor in an indoor environment. The framework integrates sensor readings from an Inertial Measurement Unit (IMU), a camera-based object detection…

High-contrast imaging (HCI) observations of exoplanets can be limited by the island effect (IE). On the current generation of telescopes, the IE becomes a severe problem when the ground wind speed is below a few meters per second. This is…

Silicon photonic wavefront phase-tilt sensors for wavefront monitoring using surface coupling grating arrays are demonstrated. The first design employs the intrinsic angle dependence of the grating coupling efficiency to determine local…

The recent IRLOS upgrade for VLT/MUSE narrow field mode (NFM) introduced a full-pupil mode to enhance sensitivity and sky coverage. This involved replacing the 2x2 Shack-Hartmann sensor with a single lens for full-aperture photon…

Instrumentation and Methods for Astrophysics · Physics 2024-06-14 Arseniy Kuznetsov , Sylvain Oberti , Benoit Neichel , Thierry Fusco

Dark wavefront sensing takes shape following quantum mechanics concepts in which one is able to "see" an object in one path of a two-arm interferometer using an as low as desired amount of light actually "hitting" the occulting object. A…

A new physically based method to estimate hemispheric-directional reflectance factor (HDRF) from lightweight multispectral cameras that have a downwelling irradiance sensor is presented. It combines radiometry with photogrammetric computer…

Data Analysis, Statistics and Probability · Physics 2019-05-10 Klaus Schneider-Zapp , Manuel Cubero-Castan , Dai Shi , Christoph Strecha

Accurate and robust wavefront reconstruction methods for pyramid wavefront sensors are in high demand as these sensors are planned to be part of many instruments currently under development for ground based telescopes. The pyramid sensor…

Instrumentation and Methods for Astrophysics · Physics 2018-11-14 Victoria Hutterer , Ronny Ramlau

Differentiating between an exoplanet signal and residual speckle noise is a key challenge in high-contrast imaging. Speckles are due to a combination of fast, slow and static wavefront aberrations introduced by atmospheric turbulence and…

The binary neutron star coalescence GW170817 was observed by gravitational wave detectors during the inspiral phase but sensitivity in the 1-5 kHz band was insufficient to observe the expected nuclear matter signature of the merger itself,…

The weak-lensing science of the LSST project drives the need to carefully model and separate the instrumental artifacts from the intrinsic lensing signal. The dominant source of the systematics for all ground based telescopes is the spatial…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 M. James Jee , J. Anthony Tyson

We have designed a plenoptic sensor to retrieve phase and amplitude changes resulting from a laser beam's propagation through atmospheric turbulence. Compared with the commonly restricted domain of (-pi, pi) in phase reconstruction by…

Optics · Physics 2023-07-19 Chensheng Wu , Jonathan Ko , Christopher C. Davis

We propose a novel control approach that combines offline supervised learning to address the challenges posed by non-linear phase reconstruction using unmodulated pyramid wavefront sensors (P-WFS) and online reinforcement learning for…

Instrumentation and Methods for Astrophysics · Physics 2024-05-24 Bartomeu Pou , Jeffrey Smith , Eduardo Quinones , Mario Martin , Damien Gratadour

Narrowband perfect absorbers are interesting for spectrum sensing, molecular detection, and infrared imaging. However, their design remains constrained by intuitive, iterative methods that lack flexibility, while also facing challenges in…

Optics · Physics 2026-02-04 H. Shen , T. Wang , X. Yao , O. Wu , C. Xie , C. Qian , H. Chen , T. Wang

The segmentation of the telescope pupil (by spiders & the segmented M4) create areas of phase isolated by the width of the spiders on the wavefront sensor (WFS), breaking the spatial continuity of the wavefront. The poor sensitivity of the…

Four-wave mixing (FWM) is an important nonlinear optical phenomenon that underlines many of the discoveries and device applications since the laser was invented. Examples include parametric amplification, mode-locked pulses and frequency…

In this work we compare the Canonical and Hadamard bases for in-situ wavefront correction of a focused Gaussian beam using a spatial light modulator (SLM). The beam is perturbed with a transparent optical element (sparse) or a random…

Image and Video Processing · Electrical Eng. & Systems 2022-12-21 Dennis Scheidt , Pedro A. Quinto Su
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