Results 51 to 60 of about 5,559 (209)

Wavefront sensing with a brightest pixel selection algorithm

, 2011
Astronomical adaptive optics systems with open-loop deformable mirror control have recently come on-line. In these systems, the deformable mirror surface is not included in the wavefront sensor paths, and so changes made to the deformable mirror are not ...
A. G. Basden, Basden, Basden, E. Gendron, Foy, Gendron, Gendron, Lardière, Marchetti, Masciadri, Myers, R. M. Myers, Roddier, Simonich, Tatarski, Thomas, Thomas   +16 more
core   +2 more sources

Real-time turbulence profiling with a pair of laser guide star Shack–Hartmann wavefront sensors for wide-field adaptive optics systems on large to extremely large telescopes [PDF]

, 2010
Real-time turbulence profiling is necessary to tune tomographic wavefront reconstruction algorithms for wide-field adaptive optics (AO) systems on large to extremely large telescopes, and to perform a variety of image post-processing tasks involving ...
Ellerbroek, B. L., Gilles, L.
core   +1 more source

Dynamic Retinal Pathology in Glaucoma Progression Revealed by High‐Resolution Functional Imaging In Vivo

Laser &Photonics Reviews, Volume 20, Issue 5, 6 March 2026.
In this work, we investigated the dynamic retinal pathology of glaucoma from onset to late stages through longitudinal in vivo high‐resolution imaging in a silicone oil‐induced ocular hypertension (SOHU) glaucoma mouse model. We developed an optimized adaptive optics two‐photon excitation fluorescence microscopy (AO‐TPEFM) technique for morphological ...
Yiming Fu, Pham Binh Minh, Sicong He, Yingzhu He, Zhongya Qin, Ting Xie, Jianan Qu   +6 more
wiley   +1 more source

Parafoveal and Perifoveal Accommodation Response to Defocus Changes Induced by a Tunable Lens

Applied Sciences, 2023
The accommodative response of the human eye is predominantly driven by foveal vision, but reacts also to off-foveal stimuli. Here, we report on monocular accommodation measurements using parafoveal and perifoveal annular stimuli centered around the fovea
Najnin Sharmin, Petros Papadogiannis, Dmitry Romashchenko, Linda Lundström, Brian Vohnsen   +4 more
doaj   +1 more source

Ground-layer wavefront reconstruction from multiple natural guide stars [PDF]

, 2007
Observational tests of ground layer wavefront recovery have been made in open loop using a constellation of four natural guide stars at the 1.55 m Kuiper telescope in Arizona.
Athey A., Baranec C., Casali M., Christoph Baranec, Egner S. E., Ellerbroek B. L., Ellerbroek B. L., Fabricant D., Johns M., Le Louarn M., Lloyd-Hart M., Lloyd-Hart M., Michael Lloyd‐Hart, Morris T. J., N. Mark Milton, Stoesz J., Szeto K., Velur V.   +17 more
core   +3 more sources

Holographic imaging with a Shack-Hartmann wavefront sensor

Optics Express, 2016
A high-resolution Shack-Hartmann wavefront sensor has been used for coherent holographic imaging, by computer reconstruction and propagation of the complex field in a lensless imaging setup. The resolution of the images obtained with the experimental data is in a good agreement with the diffraction theory. Although a proper calibration with a reference
Hai Gong, Oleg Soloviev, Dean Wilding, Paolo Pozzi, Michel Verhaegen, Gleb Vdovin   +5 more
openaire   +2 more sources

Traceable calibration of Shack–Hartmann wavefront sensors employing spherical wavefronts [PDF]

Optical Engineering, 2020
Traceable, highly accurate calibration of wavefront sensors such as Shack–Hartmann sensors is a challenging task and an active field of research. We have developed a measurement system for the traceable calibration of wavefront sensors employing spherical wavefronts and a point light source in combination with a three-axis linear stage.
Johannes Bautsch, Markus Schake, Gerd Ehret, Ulrich Berg, Lorenz Wagner, Johannes Pfund, Rainer Tutsch   +6 more
openaire   +1 more source

Natural Convection of MHD Double Diffusive Nanoencapsulated Phase Change Material (NEPCM) in the Annulus Between Concentric Horizontal Circular and Square Cylinders

International Journal of Energy Research, Volume 2026, Issue 1, 2026.
The investigation focuses on the natural convection of magnetohydrodynamic (MHD) double‐diffusive nanoencapsulated phase change material (NEPCM) in an annulus composed of square and concentric horizontal circular cylinders. The right, upper, and bottom walls of the outer square cylinder are cooled, while the inner circular cylinder is heated. The NEPCM
Md. Mahadul Islam, Md. Mamun Molla, Preetom Nag, Md. Mahbub Alam, Souhail Souai, Suresh Kannan Balasingam   +5 more
wiley   +1 more source

An Optical Wavefront Sensor Based on a Double Layer Microlens Array

Sensors, 2011
In order to determine light aberrations, Shack-Hartmann optical wavefront sensors make use of microlens arrays (MLA) to divide the incident light into small parts and focus them onto image planes.
Hsiang-Chun Wei, Guo-Dung John Su, Hsin-Ta Hsieh, Vinna Lin   +3 more
doaj   +1 more source

A direct comparison between a MEMS deformable mirror and a liquid crystal spatial light modulator in signal-based wavefront sensing [PDF]

Journal of the European Optical Society-Rapid Publications, 2013
Aberrations degrade the performance of optical systems in terms of resolution and signal-to-noise ratio. This work explores the feasibility of a signal-based wavefront sensor, which employs a search algorithm to estimate Zernike coefficients of given ...
Jewel A. R., Akondi V., Vohnsen B.
doaj   +1 more source