Results 41 to 50 of about 55,264 (288)

High-contrast imaging at small separation: impact of the optical configuration of two deformable mirrors on dark holes [PDF]

, 2017
The direct detection and characterization of exoplanets will be a major scientific driver over the next decade, involving the development of very large telescopes and requires high-contrast imaging close to the optical axis.
Abe, L., Baudoz, P., Beaulieu, M., Gouvret, C., Martinez, P., Vakili, F.   +5 more
core   +4 more sources

Theoretical principle and design of high-imaging-quality refractive-diffractive optical elements by multifocal-simultaneous aberration-correction method

Results in Physics
Multifocal refractive-diffractive optical elements, which produce arbitrary light distribution, are widely used in lightweight and compact optical systems.
Bo Dong, Ying Yang, Changxi Xue
doaj   +1 more source

Low Spatio-Temporal Frequency Wavefront Aberration Correction Method Based on a Movable Secondary Mirror

IEEE Photonics Journal
A low frequency wavefront aberration correction method for solar telescopes based on secondary mirror movement is proposed to correct dynamic wavefront aberration during the operation of solar telescope.
Yawei Xiao, Simin Zhao, Junbo Zhang, Linhai Huang, Naiting Gu   +4 more
doaj   +1 more source

Comparison of the optical quality after SMILE and FS-LASIK for high myopia by OQAS and iTrace analyzer: a one-year retrospective study

BMC Ophthalmology, 2021
Background To compare the correction effect and optical quality after small-incision lenticule extraction (SMILE) and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK) for high myopia.
Yewei Yin, Ying Lu, Aiqun Xiang, Yanyan Fu, Yang Zhao, Yuanjun Li, Tu Hu, Kaixuan Du, Shengfa Hu, Qiuman Fu, Xiaoying Wu, Dan Wen   +11 more
doaj   +1 more source

Speed of gravity and gravitomagnetism

, 2005
A v_J/c correction to the Shapiro time delay seems verified by a 2002 Jovian observation by VLBI. In this Essay, this correction is interpreted as an effect of the aberration of light in an optically refractive medium which supplies an analog of Jupiter ...
Pascual-Sánchez, J. -F.
core   +1 more source

The influence of Galactic aberration on precession parameters determined from VLBI observations [PDF]

, 2010
The influence of proper motions of sources due to Galactic aberration on precession models based on VLBI data is determined. Comparisons of the linear trends in the coordinates of the celestial pole obtained with and without taking into account Galactic ...
A. M. Clerke, C. Ma, E. A. Popova, J. Kovalevsky, J. L. Fanselow, J.-C. Liu, N. Capitaine, N. Capitaine, O. J. Sovers, O. Titov, O. Titov, O. Titov, O. Titov, O. Titov, O. Titov, S. A. Klioner, S. Kopeikin, T. M. Eubanks, V. E. Zharov, V. E. Zharov, V. V. Bobylev, V. V. Bobylev, W. Schlüter, Z. M. Malkin, Z. M. Malkin, Z. M. Malkin, Z. M. Malkin, Z. M. Malkin, Z. Malkin, Z. Malkin, Z. Malkin   +30 more
core   +1 more source

Aberration correction in 3D transthoracic echocardiography

WFUMB Ultrasound Open
Three-dimensional cardiac imaging has been available in the clinic for more than two decades. Continuous improvement in image quality has occurred in this period due to the development of probe technology and beamforming techniques.
Svein-Erik Måsøy, Bastien Dénarié, Anders Sørnes, Espen Holte, Bjørnar Grenne, Torvald Espeland, Erik Andreas Rye Berg, Ole Marius Hoel Rindal, Wayne Rigby, Tore Bjåstad   +9 more
doaj   +1 more source

Efficacy and Safety Analysis of Roxarestat in Regulating Renal Anemia in Patients on Maintenance Hemodialysis

Therapeutic Apheresis and Dialysis, EarlyView.
ABSTRACT Objective To compare the efficacy and safety of roxarestat versus recombinant human erythropoietin (rhEPO) in the management of renal anemia in patients undergoing maintenance hemodialysis. Methods This was a prospective, open‐label, randomized controlled trial.
Lingling Chen, Junjie Zhu, Qiaonan Ge
wiley   +1 more source

The Infrared Imaging Spectrograph (IRIS) for TMT: optical design of IRIS imager with "Co-axis double TMA" [PDF]

, 2016
IRIS (InfraRed Imaging Spectrograph) is one of the first-generation instruments for the Thirty Meter Telescope (TMT). IRIS is composed of a combination of near-infrared (0.84--2.4 $\mu$m) diffraction limited imager and integral field spectrograph.
Harakawa, Hiroki, Hayano, Yutaka, Ikenoue, Bungo, Larkin, James, Moore, Anna, Obuchi, Yoshiyuki, Phillips, Andrew C, Saito, Sakae, Suzuki, Ryuji, Tsuzuki, Toshihiro, Uraguchi, Fumihiro, Wincentsen, James, Wright, Shelley   +12 more
core   +3 more sources

Dynamic Aberration Correction for Conformal Window of High-Speed Aircraft Using Optimized Model-Based Wavefront Sensorless Adaptive Optics

Sensors, 2016
For high-speed aircraft, a conformal window is used to optimize the aerodynamic performance. However, the local shape of the conformal window leads to large amounts of dynamic aberrations varying with look angle. In this paper, deformable mirror (DM) and
Bing Dong, Yan Li, Xin-li Han, Bin Hu
doaj   +1 more source