Correction of the “piston effect” in optical astronomical interferometry [PDF]
Astronomy and Astrophysics Supplement Series, 1997 An a posteriori method to cancel out atmospheric optical path fluctuations to achieve accurate phase restoration and spectral analysis of interferograms is presented in this paper. The correction algorithm is based on classical noise reduction methods.
openaire +1 more source
Towards Piston Fine Tuning of Segmented Mirrors through Reinforcement Learning
, 2020 Unlike supervised machine learning methods, reinforcement learning allows an entity to learn how to deploy a task from experience rather than labeled data.
Dailos Guerra-Ramos +2 more
core +1 more source
Piston Fuel Film Observations in an Optical Access GDI Engine [PDF]
SAE Technical Paper Series, 2001 <div class="htmlview paragraph">A gasoline direct injection fuel spray was observed using a fired, optical access, square cross-section single cylinder research engine and high-speed video imaging. Spray interaction with the piston is described qualitatively, and the results are compared with Computational Fluid Dynamics (CFD) simulation results ...
Rolf B. Karlsson, John B. Heywood
openaire +1 more source
Toward large diffraction limited space telescopes with the Latt lightweight active primary [PDF]
, 2017 The design of large segmented mirrors, actively controlled both in shape and in differential piston, is one of the challenges space optics is facing, driven by the needs of the astronomical ...
XOMPERO, MARCO +15 more
core +1 more source
Piston Reconstruction Experiment (P-REx) – II. Off-line performance evaluation with VLTI/GRAVITY
, 2022 For sensitive optical interferometry, it is crucial to control the evolution of the optical path difference (OPD) of the wavefront between the individual telescopes of the array.
Perera, S. +6 more
core +1 more source
Image sharpening metrics and search strategies for indirect adaptive optics [PDF]
, 2000 Adaptive optics is concerned with the correction of turbulence induced aberrations and mis-alignments in optical systems. It is an expensive and complicated technology which has been developed for astronomy and defence applications.
Doble, N., Doble, Nathan
core
Piston Sensing for Sparse Aperture Systems via All-Optical Diffractive Neural Network
IEEE Photonics Journal, 2023 It is a crucial issue to realize real-time piston correction in the area of sparse aperture imaging. This paper introduces an optical diffractive neural network-based piston sensing method, which can achieve light-speed sensing. By using detectable intensity to represent pistons, the proposed method is capable of converting complex amplitude ...
Xiafei Ma +3 more
openaire +3 more sources
Micro-stabilised sightline for missile applications [PDF]
, 2012 The feasibility of un-cooled long wave infrared (LWIR) imager line of sight (LOS) stabilization without the use of gimbals has been assessed with the aim of improving the existing performance of electro-optics (EO) sensors.
Smith, L.
core
Modeling the adaptive optics systems on the Giant Magellan Telescope
, 2016 Modeling adaptive optics (AO) systems is crucial to understanding their performance and a key aid in their design. The Giant Magellan Telescope (GMT) is planning three AO modes at first light: natural guide star AO, ground-layer AO and laser tomography ...
Rigaut, Francois +9 more
core +1 more source
Analysis and mitigation of pupil discontinuities on adaptive optics performance
, 2018 International audienceAs already noticed in other telescopes, the presence of large telescope spiders and of a segmented deformable mirror in an Adaptive Optics system leads to pupil fragmentation and may create phase discontinuities.
Dohlen, Kjetil +10 more
core +1 more source