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The use of Adaptive Optics in Extremely Large Telescopes brings new challenges, one of which is the treatment of Shack-Hartmann Wavefront sensors images. When using this type of sensors in conjunction with laser guide stars for sampling the…

Instrumentation and Methods for Astrophysics · Physics 2014-04-10 A. T. Mello , A. Kanaan , D. Guzman , A. Guesalaga

Direct imaging of exoplanet systems requires the use of coronagraphs to reach high contrast levels (10^-8 to 10^-11) at small angular separations (0.1"). However, the performance of these devices is drastically limited by aberrations (in…

Instrumentation and Methods for Astrophysics · Physics 2017-10-11 Johan Mazoyer , Raphaël Galicher , Pierre Baudoz , Patrick Lanzoni , Frédéric Zamkotsian , Gérard Rousset

Interference-fit joints are typically adopted to produce permanent assemblies among mechanical parts. The resulting contact pressure is generally used for element fixing or to allow load transmission. Nevertheless, some special designs take…

Optics · Physics 2021-12-08 Luca Esposito , Alcide Bertocco , Matteo Bruno , Andrew Ruggiero

We have developed a real-space method to correct distortion due to thermal drift and piezoelectric actuator nonlinearities on scanning tunneling microscope images using Matlab. The method uses the known structures typically present in…

Instrumentation and Detectors · Physics 2017-02-03 Mitchell P. Yothers , Aaron E. Browder , Lloyd A. Bumm

The new frontier in the quest for the highest contrast levels in the focal plane of a coronagraph is now the correction of the large diffractive artifacts effects introduced at the science camera by apertures of increasing complexity. The…

Instrumentation and Methods for Astrophysics · Physics 2016-01-18 Johan Mazoyer , Laurent Pueyo , Colin Norman , Mamadou N'Diaye , Roeland P. van der Marel , Rémi Soummer

We present a technique for the accurate estimation of large-scale errors in an antenna surface using astronomical sources and detectors. The technique requires several out-of-focus images of a compact source and the signal-to-noise ratio…

Astrophysics · Physics 2009-11-11 B. Nikolic , R. E. Hills , J. S. Richer

Context. The diffusion of adaptive optics systems in astronomical instrumentation for large ground-based telescopes is rapidly increasing and the pyramid wavefront sensor is replacing the Shack-Hartmann as the standard solution for single…

Instrumentation and Methods for Astrophysics · Physics 2023-09-27 Guido Agapito , Enrico Pinna , Simone Esposito , Cedric Taïssir Heritier , Sylvain Oberti

We describe the preliminary optimized layout for a partially optimized concept of an optical-8m class VLT-like 2x2 segmented camera where each channel is assisted by an equivalent of an MCAO system where the ground layer correction is…

The size of the optics used in observatories is often limited by fabrication, metrology, and handling technology, but having a large primary mirror provides significant benefits for scientific research. The evolution of rocket launch…

Instrumentation and Methods for Astrophysics · Physics 2023-10-20 Heejoo Choi , Young-Sik Kim , Hyukmo Kang , Solvay Blomquist , Hill Tailor , Douglas Kelly , Mike Eiklenborg , Ewan S. Douglas , Daewook Kim

Based on the background of the 2021 Higher Education Club Cup National College Students Mathematical Contest in Modeling A, according to the relevant data of the China Sky Eye (FAST) radio telescope, the main cable nodes and actuators are…

Optimization and Control · Mathematics 2022-04-13 Tongyue Shi , Siyu Tao , Haining Wang

Selene is the attempt to implement a new scheme for high-intensity specular reflectometry. Instead of a highly collimated beam one uses a convergent beam covering a large angular range. The angular resolution is then performed by a…

Instrumentation and Detectors · Physics 2011-02-15 J. Stahn , U. Filges , T. Panzner

We present a concept of a millimeter wavefront sensor that allows real-time sensing of the surface of a ground-based millimeter/submillimeter telescope. It is becoming important for ground-based millimeter/submillimeter astronomy to make…

Adaptive optical correction is an efficient technique to obtain high-resolution images of the retinal surface. A main limitation of adaptive optical correction, however, is the small size of the corrected image. For medical purposes it is…

Optics · Physics 2015-03-27 Aglae Kellerer

The Vera C. Rubin Observatory will, over a period of 10 years, repeatedly survey the southern sky. To ensure that images generated by Rubin meet the quality requirements for precision science, the observatory will use an Active Optics…

(abridged) Extreme adaptive optics (XAO) encounters severe difficulties to cope with the high speed (>1kHz), high accuracy and high order requirements for future extremely large telescopes. An innovative high order adaptive optics system…

Instrumentation and Methods for Astrophysics · Physics 2015-09-29 Christian Delacroix , Maud Langlois , Magali Loupias , Eric Thiébaut , Louisa Adjali , Jonathan Leger , Michel Tallon

We explore the impact of different telescope apertures on the image simulation and deconvolution processes within the context of a synthetic star field. Using HCIPy and Python programming, we modelled six telescope apertures namely…

Instrumentation and Methods for Astrophysics · Physics 2024-02-09 Jyotika Roychowdhury , Kevin Derby , Daewook Kim

The James Webb Space Telescope is orders of magnitude more sensitive than any other facility across the near to mid-infrared wavelengths. Many approved programs take advantage of its highly stable point spread function (PSF) to directly…

Precise manipulation of small objects using light holds transformative potential across diverse fields. While research in optical trapping and manipulation predominantly relies on the attraction of solid matter to light intensity maxima,…

Optics · Physics 2025-04-28 Adeel Afridi , Bruno Melo , Nadine Meyer , Romain Quidant

Optical coherence tomography (OCT) is a micrometer-scale, volumetric imaging modality that has become a clinical standard in ophthalmology. OCT instruments image by raster-scanning a focused light spot across the retina, acquiring…

Image and Video Processing · Electrical Eng. & Systems 2022-09-16 Stefan Ploner , Siyu Chen , Jungeun Won , Lennart Husvogt , Katharina Breininger , Julia Schottenhamml , James Fujimoto , Andreas Maier

Uplink pre-compensation in ground-to-satellite optical links remains a problem, with an appropriate measurement of the wavefront error in the uplink path often not being available. We present a method that uses successive measurements of…

Instrumentation and Detectors · Physics 2025-09-12 Alex Frost , Nicolas Maron , Shane Walsh , Benjamin Dix-Matthews , Sascha Schediwy , Michael Hart