Results 71 to 80 of about 30,065 (244)

Real-time Adaptive Optics with pyramid wavefront sensors: Accurate wavefront reconstruction using iterative methods

, 2018
In this paper, we address the inverse problem of fast, stable, and high-quality wavefront reconstruction from pyramid wavefront sensor data for Adaptive Optics systems on Extremely Large Telescopes.
Hutterer, Victoria, Ramlau, Ronny, Shatokhina, Iuliia   +2 more
core   +1 more source

Results from the GMT Ground-Layer Experiment at the Magellan Telescopes [PDF]

, 2006
We present results from our two year study of ground-layer turbulence as seen through the 6.5-meter Magellan Telescopes at Las Campanas Observatory. The experiment consists of multiple, moderate resolution, Shack-Hartmann wavefront sensors deployed over ...
Athey, A., Phillips, M., Shectman, S., Thomas-Osip, J.   +3 more
core   +3 more sources

Deep Learning Correction Algorithm for The Active Optics System

Sensors, 2020
The correction of wavefront aberration plays a vital role in active optics. The traditional correction algorithms based on the deformation of the mirror cannot effectively deal with disturbances in the real system.
Wenxiang Li, Chao Kang, Hengrui Guan, Shen Huang, Jinbiao Zhao, Xiaojun Zhou, Jinpeng Li   +6 more
doaj   +1 more source

Self-coherent camera as a focal plane wavefront sensor: simulations

, 2009
Direct detection of exoplanets requires high dynamic range imaging. Coronagraphs could be the solution, but their performance in space is limited by wavefront errors (manufacturing errors on optics, temperature variations, etc.), which create quasi ...
Baudoz, Pierre, Galicher, Raphael, Mas, Marion, Rousset, Gerard, Totems, Julien   +4 more
core   +3 more sources

High-speed imaging and wavefront sensing with an infrared avalanche photodiode array [PDF]

, 2015
Infrared avalanche photodiode arrays represent a panacea for many branches of astronomy by enabling extremely low-noise, high-speed and even photon-counting measurements at near-infrared wavelengths.
Atkinson, Dani, Baranec, Christoph, Chun, Mark, Hall, Donald, Jacobson, Shane, Law, Nicholas M., Riddle, Reed   +6 more
core   +3 more sources

Study of Free‐Space Optical Quantum Network: Review and Prospectives

Advanced Science, EarlyView.
Free from the constraints of fiber connections, free‐space quantum network enables longer and more flexible quantum network connections. This review summarizes and comparatively analyzes free‐space quantum network experiments based on ground stations, satellites, and mobile platforms.
Hua‐Ying Liu, Zhenda Xie, Shining Zhu
wiley   +1 more source

Recovering pyramid WS gain in non-common path aberration correction mode via deformable lens

, 2017
It is by now well known that pyramid based wavefront sensors, once in closed loop, have the capability to improve more and more the gain as the reference natural star image size is getting smaller on the pyramid pin. Especially in extreme adaptive optics
Bergomi, M., Bonora, S., Chinellato, S., Favazza, P., Magrin, D., Quintavalla, M., Ragazzoni, R., Umbriaco, G.   +7 more
core   +1 more source

All‐in‐One Underwater Quality Evaluation Metamaterial With Mechanical Robustness, Sound Attenuation, and Diffuse Reflection

Advanced Science, EarlyView.
In this work, a bioinspired all‐in‐one underwater quality evaluation metamaterial, combining sound attenuation, diffuse reflection, and mechanical robustness, is proposed based on jumping spider locomotion and human skeletal biomechanics. Meanwhile, a CNN‑driven quality evaluation framework is established for theoretically dimension‐reduced ...
Hongze Li, Zhenyu Li, Jinshui Yang, Jianhao Wu, Yidan Chen, Linzhi Wu, Hong Hu, Penglin Gao, Yegao Qu   +8 more
wiley   +1 more source

Wavefront sensing from the image domain with the Oxford-SWIFT integral field spectrograph

, 2014
The limits for adaptive-optics (AO) imaging at high contrast and high resolution are determined by residual phase errors from non-common-path aberrations not sensed by the wavefront sensor, especially for integral field spectrographs, where phase ...
Burruss, Rick, Clarke, Fraser, Cotter, Garret, Pope, Benjamin, Tecza, Matthias, Thatte, Niranjan   +5 more
core   +1 more source

The wavefront of the radio signal emitted by cosmic ray air showers [PDF]

, 2014
Analyzing measurements of the LOPES antenna array together with corresponding CoREAS simulations for more than 300 measured events with energy above $10^{17}\,$eV and zenith angles smaller than $45^\circ$, we find that the radio wavefront of cosmic-ray ...
Apel, W. D., Arteaga-Velázquez, J. C., Bekk, K., Bertaina, M., Biermann, P. L., Blümer, J., Bozdog, H., Brancus, I. M., Bähren, L., Cantoni, E., Chiavassa, A., Daumiller, K., De Souza, V., Doll, P., Engel, R., Falcke, H., Fuchs, B., Gemmeke, H., Grupen, C., Haungs, A., Heck, D., Horneffer, A., Huber, D., Huege, T., Hörandel, J. R., Isar, P. G., Kampert, K.-H., Kang, D., Krömer, O., Kuijpers, J., Link, K., LOPES Collaboration, Ludwig, M., Mathes, H. J., Melissas, M., Morello, C., Oehlschläger, J., Palmieri, N., Pierog, T., Pierro, F. D., Rautenberg, J., Rebel, H., Roth, M., Rühle, C., Saftoiu, A., Schieler, H., Schmidt, A., Schoo, S., Schröder, F. G., Sima, O., Toma, G., Trinchero, G. C., Uczak, P., Weindl, A., Wochele, J., Zabierowski, J., Zensus, J. A.   +56 more
core   +3 more sources