Results 21 to 30 of about 325,753 (218)
Optics Express, 2021 Coherent beam combination (CBC) holds promise for scaling the output power of the laser system while maintaining good beam quality. Owing to the thermal effect and mechanics instability, piston and tilt distortions always exist and affect the performance
Qi Chang +6 more
semanticscholar +1 more source
Sensors, 2010 Since the beginning of the Mars planet exploration, the characterization of carbon dioxide hypersonic flows to simulate a spaceship’s Mars atmosphere entry conditions has been an important issue.
Raphäel Vallon +5 more
doaj +1 more source
Confusion in differential piston measurement with the pyramid wavefront sensor
Astronomy & Astrophysics, 2021 Context. The pyramid was proven to be a highly sensitive and versatile wave-front sensor (WFS) and has been selected to be installed on the single conjugate adaptive optics (AO) systems of the extremely large telescope (ELT).
A. Bertrou-Cantou +6 more
semanticscholar +1 more source
Optics Express, 2021 To realize the large-scale and high-precision co-phasing adjustment of synthetic-aperture telescopes, we propose a multichannel left-subtract-right feature vector piston error detection method based on a convolutional neural network, which inherits the ...
Pengfei Wang +5 more
semanticscholar +1 more source
IEEE Photonics Journal, 2017 A novel approach of tip/tilt control through optimizing laser beam coupling efficiencies from space to polarization-maintaining-fibers with stochastic parallel gradient descent (SPGD) algorithm for coherent beam combining (CBC) applications is ...
Feng Li +5 more
doaj +1 more source
Operation of a MOEMS Deformable Mirror in Cryo: Challenges and Results
Micromachines, 2017 Micro-opto-electro-mechanical systems (MOEMS) Deformable Mirrors (DM) are key components for next generation optical instruments implementing innovative adaptive optics systems, both in existing telescopes and in the future ELTs.
Frederic Zamkotsian +5 more
doaj +1 more source
Piston Sensing for Sparse Aperture Systems via All-Optical Diffractive Neural Network
IEEE Photonics Journal, 2023 It is a crucial issue to realize real-time piston correction in the area of sparse aperture imaging. This paper introduces an optical diffractive neural network-based piston sensing method, which can achieve light-speed sensing. By using detectable intensity to represent pistons, the proposed method is capable of converting complex amplitude ...
Xiafei Ma +3 more
openaire +3 more sources
Scientific Reports, 2017 In this paper, we experimentally validate a tiled-aperture conformal projection system with the largest array filling factor and element beam truncation factor to the best of our knowledge. The conformal projection system, which is made up of a hexagonal
Dong Zhi +7 more
doaj +1 more source
Turbulence scale effects and resolution requirements in aero-optics.
Applied Optics, 2021 While optical aberrations caused by atmospheric turbulence have been extensively investigated and well characterized, recent research has identified structural differences in optical phase distortions caused by aircraft-induced, compressible turbulence ...
Edwin Mathews +3 more
semanticscholar +1 more source
Advanced Engineering Materials, EarlyView.Prestraining the substrate influences coating formation process. Higher prestraining force leads to higher coating thickness and lower hardness. Increase in prestraining force enhances preliminary damage in hard anodic coating. Fatigue damage mechanisms change for hard anodized prestrained samples.
Linto George Thomas +4 more
wiley +1 more source