Results 41 to 50 of about 2,243,893 (300)

Direct observation of atmospheric turbulence with a video-rate wide-field wavefront sensor

Nature Photonics
Turbulence is a complex and chaotic state of fluid motion. Atmospheric turbulence within the Earth’s atmosphere poses fundamental challenges for applications such as remote sensing, free-space optical communications and astronomical observation due to ...
Yuduo Guo, Yuhan Hao, Sen Wan, Hao Zhang, Laiyu Zhu, Yi Zhang, Jiamin Wu, Qionghai Dai, Lu Fang   +8 more
semanticscholar   +1 more source

Large dynamic range Shack-Hartmann wavefront sensor based on adaptive spot matching

Light: Advanced Manufacturing
The Shack-Hartmann wavefront sensor (SHWS) is widely used for high-speed, precise, and stable wavefront measurements. However, conventional SHWSs encounter a limitation in that the focused spot from each microlens is restricted to a single microlens ...
Jiamiao Yang, Jichong Zhou, Lirong Qiu, Rongjun Shao, Linxian Liu, Qiaozhi He   +5 more
semanticscholar   +1 more source

Digital holographic wavefront sensor

, 2022
Paper AOT2D.1For free-space laser communications and for tracking of high-speed airborne objects Shack-Hartmann sensor is not effective. Its performance is limited by scintillation.
Gladysz, Szymon, Zepp, Andreas, Palomo, Pablo Marin   +2 more
core   +1 more source

Adaptable Shack-Hartmann wavefront sensor with diffractive lenslet arrays to mitigate the effects of scintillation.

Optics Express, 2020
Adaptive optics systems are used to compensate for distortions of the wavefront of light induced by turbulence in the atmosphere. Shack-Hartmann wavefront sensors are used to measure this wavefront distortion before correction.
D. Lechner, A. Zepp, M. Eichhorn, S. Gładysz   +3 more
semanticscholar   +1 more source

Differential Wavefront Curvature Sensor

, 2005
In this paper, a wavefront curvature sensor is presented. This sensor is based on the measurements of the differentials of wavefront slopes, where the wavefront slope measurements can be achieved by a Shack-Hartmann sensor.
Zou, Weiyao, Rolland, Jannick
core   +1 more source

Using the generalised-optical differentiation wavefront sensor for laser guide star wavefront sensing [PDF]

, 2020
Laser guide stars (LGS) are used in many adaptive optics systems to extend sky coverage. The most common wavefront sensor used in combination with a LGS is a Shack-Hartmann wavefront sensor (SHWFS). The ShackHartmann has a major disadvantage for extended
Dekany, Richard G., Haffert, S.Y., Keller, Christoph U., Keller, C.U., Haffert, Sebastiaan Y., Dekany, R., Dekany, Richard   +6 more
core   +1 more source

On-sky correction of non-common path aberration with the pyramid wavefront sensor

Astronomy & Astrophysics, 2020
The paper deals with with the on-sky performance of the pyramid wavefront sensor-based Adaptive Optics (AO) systems. These wavefront sensors are of great importance, being used in all first light AO systems of the ELTs (E-ELT, GMT, and TMT), currently in
S. Esposito, A. Puglisi, E. Pinna, G. Agapito, F. Quirós-Pacheco, J. Véran, G. Herriot   +6 more
semanticscholar   +1 more source

Visible and Near-infrared Laboratory Demonstration of a Simplified Pyramid Wavefront Sensor [PDF]

Publications of the Astronomical Society of the Pacific, 2019
Wavefront sensing and control are important for enabling one of the key advantages of using large apertures, namely higher angular resolution. Pyramid wavefront sensors are becoming commonplace in new instrument designs owing to their superior ...
J. Lozi, N. Jovanovic, O. Guyon, M. Chun, S. Jacobson, S. Goebel, F. Martinache   +6 more
semanticscholar   +1 more source

Chiral Phase Change Nanomaterials

Advanced Functional Materials, EarlyView.
This work demonstrates reversible, non‐volatile phase transitions in chiral Ge2${\rm Ge}_2$Sb2${\rm Sb}_2$Te5${\rm Te}_5$ (GST) nanohelices for high‐speed optical modulation of chirality and dynamic control of the state of polarization (SOP). The chiral nanostructures are fabricated using a highly directional, wafer‐scale physical vapor deposition ...
Joshua A. Burrow, Md Shah Alam, Riad Yahiaoui, Evan M. Smith, Ryan Laing, Jules Gardener, Thomas A. Searles, Piyush J. Shah, Shivashankar Vangala, Joshua R. Hendrickson, Andrew M. Sarangan, Imad Agha   +11 more
wiley   +1 more source

Hartmann wavefront sensors and their application at FLASH [PDF]

Journal of Synchrotron Radiation, 2016
Different types of Hartmann wavefront sensors are presented which are usable for a variety of applications in the soft X-ray spectral region at FLASH, the free-electron laser (FEL) in Hamburg. As a typical application, online measurements of photon beam parameters during mirror alignment are reported on.
Keitel, Barbara, Ploenjes, Elke, Kreis, Svea, Kuhlmann, Marion, Tiedtke, Kai, Mey, Tobias, Schaefer, Bernd, Mann, Klaus   +7 more
openaire   +4 more sources