Results 51 to 60 of about 93,717 (313)
Deep learning wavefront sensing
Optics Express, 2019 We present a new class of wavefront sensors by extending their design space based on machine learning. This approach simplifies both the optical hardware and image processing in wavefront sensing. We experimentally demonstrated a variety of image-based wavefront sensing architectures that can directly estimate Zernike coefficients of aberrated ...
Yohei Nishizaki +6 more
openaire +3 more sources
Wavefront sensing reveals optical coherence [PDF]
Nature Communications, 2014 Wavefront sensing is a set of techniques providing efficient means to ascertain the shape of an optical wavefront or its deviation from an ideal reference. Due to its wide dynamical range and high optical efficiency, the Shack-Hartmann is nowadays the most widely used of these sensors.
B. Stoklasa +4 more
openaire +4 more sources
Wavefront sensing using diffractive elements [PDF]
Optics Letters, 2012 In this Letter, we introduce a wavefront slope sensor based on a diffractive element. The diffractive element wavefront sensor (DEWS) produces four double overlapping copies of the incoming wavefront acting like a combination of shearing and pyramidal sensors. The DEWS allows a simple and fast slope estimate.
Pérez Cagigal, Manuel +1 more
openaire +4 more sources
Transmission wavefront shearing interferometry for photoelastic materials [PDF]
, 2009 A general analysis and experimental validation of transmission wavefront shearing interferometry for photoelastic materials are presented. These interferometers applied to optically isotropic materials produce a single interference pattern related to one
Bhattacharya, Kaushik +2 more
core +1 more source
Rebuilding ships while at sea—Character individuality, homology, and evolutionary innovation
Journal of Morphology, Volume 284, Issue 1, January 2023., 2023 Building on a previous account of evolutionary innovation, I propose here that evolutionary novelties are those individualized characters that are not homologous to any characters in the ancestor. Integrating functional and structural perspectives, I argue that functional as well as structural considerations are important for character ...
Gerhard Schlosser
wiley +1 more source
Adaptive Optics Methods to Rat Eye Properties: Impact of Pupil Diameter on Wavefront Detection
PhotonicsAchieving a high-quality wavefront sensing light spot and accurate wavefront estimation of the rat eye is still challenging due to its large ocular aberrations and the back reflections from fundus multilayer.
Wen Kong +3 more
doaj +1 more source
High Sensitivity Wavefront Sensing with a non-linear Curvature Wavefront Sensor [PDF]
, 2009 A new wavefront sensing approach, derived from the successful curvature wavefront sensing concept but using a non-linear phase retrieval wavefront reconstruction scheme, is described. The non-linear curvature wavefront sensor (nlCWFS) approaches the theoretical sensitivity limit imposed by fundamental physics by taking full advantage of wavefront ...
arxiv +1 more source
Multiple spatial frequencies wavefront sensing [PDF]
Proceedings of the Adaptive Optics for Extremely Large Telescopes 5, 2017 We describe the concept of splitting spatial frequency perturbations into some kind of pupil planes wavefront sensors. Further to the existing approach of dropping higher spatial frequency to suppress aliasing effects (the so-called spatial filtered Shack-Hartmann), we point out that spatial frequencies splitting and mixing of these in a proper manner,
Magrin, Demetrio +12 more
openaire +4 more sources
The coronagraphic Modal Wavefront Sensor: a hybrid focal-plane sensor for the high-contrast imaging of circumstellar environments [PDF]
, 2016 The raw coronagraphic performance of current high-contrast imaging instruments is limited by the presence of a quasi-static speckle (QSS) background, resulting from instrumental non-common path errors (NCPEs).
Keller, Christoph U. +4 more
core +3 more sources
IEEE Photonics Journal, 2016 We describe a sequential operation approach for a three-sided pyramid wavefront sensor (PWFS) based on a micromirror array with hexagonal geometry. The geometrical optics analysis and numerical simulations show that a linear relationship exists between ...
Lu Chen +6 more
doaj +1 more source