Focal-plane-assisted pyramid wavefront sensor: Enabling frame-by-frame optical gain tracking

  title={Focal-plane-assisted pyramid wavefront sensor: Enabling frame-by-frame optical gain tracking},
  author={Vincent Chambouleyron and Olivier Fauvarque and Jean-François Sauvage and Benoı̂t Neichel and Thierry Fusco},
  journal={Astronomy \& Astrophysics},
Aims. With its high sensitivity, the pyramid wavefront sensor (PyWFS) is becoming an advantageous sensor for astronomical adaptive optics (AO) systems. However, this sensor exhibits significant non-linear behaviours leading to challenging AO control issues. Methods. In order to mitigate these effects, we propose to use in addition to the classical pyramid sensor a focal plane image combined with a convolutive description of the sensor to fast track the PyWFS non-linearities, the so-called… 

High contrast imaging wavefront sensor referencing from coronagraphic images

The algorithm DrWHO - Direct Reinforcement Wavefront Heuristic Optimisation - is an image-based lucky imaging approach, aimed at finding and continuously updating the ideal reference of the wavefront sensor (WFS) that includes the NCPA, and updating this new reference to the WFS.

A pyramid-based adaptive optics for the high-resolution echelle spectrograph at SAO RAS 6-m telescope

We propose a design of an adaptive optics (AO) system for the high-resolution fiber-fed echelle spectrograph installed at the Nasmyth focus of the 6-m BTA telescope at the Special Astrophysical

Imaged-based adaptive optics wavefront sensor referencing for high contrast imaging

A key challenge of high contrast imaging (HCI) is to differentiate a speckle from an exoplanet signal. The sources of speckles are a combination of atmospheric residuals and aberrations in the

The phase-shifted Zernike wave-front sensor

The next generation of Giant Fragmented Telescopes will allow the study of faint and distant objects such as exoplanets. But the structure of the telescope also brings new challenges such as pupil

HARMONI at ELT: wavefront control in SCAO mode

HARMONI is the first light visible and near-IR integral field spectrograph for the ELT. It covers a large spectral range from 450nm to 2450nm with resolving powers from 3500 to 18000 and spatial

Current status of PAPYRUS: the pyramid based adaptive optics system at LAM/OHP

The Provence Adaptive optics Pyramid Run System (PAPYRUS) is a pyramid-based Adaptive Optics (AO) system that will be installed at the Coude focus of the 1.52m telescope (T152) at the Observatoire de



Pyramid wavefront sensor optical gains compensation using a convolutional model

A new theoretical description of the PyFWS, which uses a convolutional model to describe the sensor, is analyzed and it is shown that an accurate estimation of the OGs is possible by only using the AO telemetry data to derive statistical information of the turbulence, and the method is then fully non-invasive.

A telescope-ready approach for modal compensation of pyramid wavefront sensor optical gain

The pyramid wavefront sensor (PWFS) is the currently preferred design for high-sensitivity adaptive optics (AO) systems for extremely large telescopes (ELTs). Yet, nonlinearities of the signal

Adaptive optics with programmable Fourier-based wavefront sensors: a spatial light modulator approach to the LOOPS testbed

Wavefront sensors encode phase information of an incoming wavefront into an intensity pattern that can be measured on a camera. Several kinds of wavefront sensors (WFS) are used in astronomical

Pyramid Wavefront Sensor behavior in partial correction Adaptive Optic systems

In this letter we evaluate the limiting magnitude for a Pyramid Sensor operating in a closed loop astronomical Adaptive Optics system. A first heuristic analysis has shown that, when a point-like

Limits of Adaptive Optics for High-Contrast Imaging

The effects of photon noise, aliasing, wave front chromaticity, and scintillation on the point-spread function (PSF) contrast achievable with ground-based adaptive optics (AO) are evaluated for

Adaptive optics with programmable Fourier-based wavefront sensors: a spatial light modulator approach to the LAM/ONERA on-sky pyramid sensor testbed

The LAM/ONERA on-sky pyramid sensor (LOOPS) adaptive optics testbed hosted at the Laboratoire d’Astrophysique de Marseille has been upgraded by adding a spatial light modulator (SLM) that produces high-definition phase masks that mimic otherwise bulk optic devices.

Kernel formalism applied to Fourier-based wave-front sensing in presence of residual phases.

This work describes Fourier-based wave-front sensors (WFSs) as linear integral operators, characterized by their kernel, and shows that convolutional kernels allow to drastically simplify the WFS model by summarizing its behavior in a concise and comprehensive quantity called the W FS impulse response.

Adaptive Optics for Extremely Large Telescopes

  • S. Hippler
  • Physics
    Journal of Astronomical Instrumentation
  • 2019
Adaptive Optics (AO) has become a key technology for the largest ground-based telescopes currently under, or close to beginning of, construction. AO is an indispensable component and has basically

Adaptive Optics

The detectability of an interference signal will depend on the visibility of the fringes. Resolved sources will have low visibility in any case, and it is important to minimize losses of visibility