Results 41 to 50 of about 6,059 (275)
A new low-cost, compact, auto-phoropter for refractive assessment in developing countries
Scientific Reports, 2017 Using a phoropter to measure the refractive error is one of the most commonly used methods by ophthalmologists and optometrists. Here, we demonstrate design and fabrication of a portable automatic phoropter with no need for patient’s feedback. The system
Babak Amirsolaimani +4 more
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IEEE Photonics Journal, 2021 The charge-coupled device-based Shaker–Hartmann wavefront sensor has been widely used to compensate for wavefront distortion in coherent optical communication.
Xu Yan +6 more
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Photonics, 2023 Atmospheric turbulence causes refractive index fluctuations, which in turn introduce extra distortions to the wavefront of the propagated radiation. It ultimately degrades telescope resolution (in imaging applications) and reduces radiation power density
Ilya Galaktionov +4 more
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Wavefront Reconstruction of Shack-Hartmann with Under-Sampling of Sub-Apertures
Photonics, 2023 Shack-Hartmann wavefront sensor plays a key role in adaptive optics (AO) systems, which detect the aberrant wavefront by an array of micro-lenslets across the aperture pupil.
Jian Huang +3 more
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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 +3 more
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X-ray wavefront characterization with two-dimensional wavefront sensors: shearing interferometers and Hartmann wavefront sensors [PDF]
SPIE Proceedings, 2012 Phase reconstructions from a two-dimensional shearing inter- ferometer, based on two orthogonal phase gratings in a single plane, and a Hartmann sensor are compared. Design alternatives for both wavefront sensors are given, and simulated performance of both the two-dimen- sional x-ray shearing interferometer and Hartmann wavefront sensor are presented ...
openaire +4 more sources
Manipulating Ferroelectric Topological Polar Structures with Twisted Light
Advanced Materials, EarlyView.We demonstrate dynamic control of ferroelectric order in quasi‐2D CsBiNb2O7 using twisted ultraviolet light carrying orbital angular momentum. Our approach harnesses non‐resonant multiphoton absorption and induced strain to modulate topological of ferroelectric polarization textures.
Nimish P. Nazirkar +10 more
wiley +1 more source
Neuromorphic Light‐Responsive Organic Matter for in Materia Reservoir Computing
Advanced Materials, EarlyView.In this work we show that light‐responsive adaptive organic matter can store and process information at the matter level, and emulate neuromorphic functionalities such as short term memory, long term memory and visual memory. Besides demonstrating that material dynamics can be exploited for spatio‐temporal event detection and motion perception, we show
Federico Ferrarese Lupi +5 more
wiley +1 more source
How to Manufacture Photonic Metamaterials
Advanced Materials Technologies, EarlyView.Metamaterials boast applications such as invisibility and “hyperlenses” with resolution beyond the diffraction limit, but these applications haven’t been exploited in earnest and the market for them hasn’t grown much likely because facile and economical methods for fabricating them without defect has not emerged.
Apurba Paul, Gregory Timp
wiley +1 more source
Mathematics, 2020 Mathematical modelling methods have several limitations when addressing complex physics whose calculations require considerable amount of time. This is the case of adaptive optics, a series of techniques used to process and improve the resolution of ...
Sergio Luis Suárez Gómez +4 more
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