Results 71 to 80 of about 43,714 (202)

Fully Convolutional Approaches for Numerical Approximation of Turbulent Phases in Solar Adaptive Optics

Mathematics, 2021
Information on the correlations from solar Shack–Hartmann wavefront sensors is usually used for reconstruction algorithms. However, modern applications of artificial neural networks as adaptive optics reconstruction algorithms allow the use of the full ...
Francisco García Riesgo, Sergio Luis Suárez Gómez, Enrique Díez Alonso, Carlos González-Gutiérrez, Jesús Daniel Santos   +4 more
doaj   +1 more source

Tolerance analysis method for Shack-Hartmann sensors using a variable phase surface [PDF]

, 2006
Even after good calibration, the measurement accuracy of a Shack-Hartmann sensor can be affected by the fabrication and alignment tolerances of the wavefront sensing optical system.
Curatu, Costin, Curatu, George, Rolland, Jannick   +2 more
core   +1 more source

Single conjugate adaptive optics for the ELT instrument METIS [PDF]

, 2018
The ELT is a 39m large, ground-based optical and near- to mid-infrared telescope under construction in the Chilean Atacama desert. Operation is planned to start around the middle of the next decade.
Absil, Olivier, Bertram, Thomas, Brandner, Wolfgang, Cantalloube, Faustine, Carlomagno, Brunella, Feldt, Markus, Hippler, Stefan, Obereder, Andreas, Shatokhina, Iuliia, Stuik, Remko   +9 more
core   +3 more sources

Effect of 0.025% atropine on ocular biometry changes during accommodation

Ophthalmic and Physiological Optics, Volume 45, Issue 3, Page 865-876, May 2025.
Abstract Purpose Low concentration atropine is an effective treatment to slow myopia progression and axial elongation and also reduces accommodation. On‐axis ocular dimensions of the eye change during accommodation; hence, this study aimed to quantify the effect of 0.025% atropine eye drops on accommodation‐induced changes in ocular biometry.
Rohan P. J. Hughes, Emily C. Woodman‐Pieterse, Scott A. Read, Stephen J. Vincent, Michael J. Collins   +4 more
wiley   +1 more source

Shack-Hartmann and Interferometric Hybrid Wavefront Sensor [PDF]

, 2011
This document reports results of wave-optics simulations used to test the performance of a hybrid wavefront sensor designed to combine the self-referencing interferometer and Shack-Hartmann wavefront sensors in an optimal way.
Ellis, Troy R.
core   +1 more source

Review and experimental comparison of speckle‐tracking algorithms for X‐ray phase contrast imaging

Journal of Synchrotron Radiation, Volume 32, Issue 1, Page 180-199, January 2025.
This review focuses on low‐dose near‐field X‐ray speckle phase imaging in the differential mode introducing the existing algorithms with their specifications and comparing their performances under various experimental conditions.X‐ray speckles have been used in a wide range of experiments, including imaging (and tomography), wavefront sensing, spatial ...
Rafael Celestre, Laurène Quénot, Christopher Ninham, Emmanuel Brun, Luca Fardin   +4 more
wiley   +1 more source

Differential Shack-Hartman Curvature Sensor [PDF]

, 2008
A differential Shack-Hartmann curvature sensor for measuring a curvature including principal curvatures and directions of a wavefront. The curvature sensor includes a Shack-Hartmann sensor with an input beam and an optical element to split said input ...
Rolland, Jannick, Zou, Weiyao
core   +2 more sources

Sources of reduced visual acuity and spectacle treatment options for individuals with Down syndrome: Review of current literature

Ophthalmic and Physiological Optics, Volume 44, Issue 7, Page 1326-1345, November 2024.
Abstract Individuals with Down syndrome are known to have a greater prevalence of ocular conditions such as strabismus, nystagmus, elevated refractive error, poor accommodative function, elevated higher‐order optical aberrations and corneal abnormalities.
Heather A. Anderson
wiley   +1 more source

Non-linear wavefront reconstruction methods for pyramid sensors using Landweber and Landweber-Kaczmarz iteration [PDF]

, 2018
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 relates the incoming wavefront and its measurements in a non-linear way.
arxiv   +1 more source

High‐angular‐sensitivity X‐ray phase‐contrast microtomography of soft tissue through a two‐directional beam‐tracking synchrotron set‐up

Journal of Synchrotron Radiation, Volume 31, Issue 5, Page 1293-1298, September 2024.
X‐ray phase‐contrast microtomography is demonstrated using two‐dimensional amplitude modulation of the beam. The implementation is characterised in terms of angular sensitivity and spatial resolution, and its application to the three‐dimensional imaging of biological soft tissues is shown.Two‐directional beam‐tracking (2DBT) is a method for phase ...
Carlos Navarrete-León, P. Stephen Patrick, Adam Doherty, Harry Allan, Silvia Cipiccia, Shashidhara Marathe, Kaz Wanelik, Michela Esposito, Charlotte K. Hagen, Alessandro Olivo, Marco Endrizzi   +10 more
wiley   +1 more source