Results 11 to 20 of about 16,325 (263)
Piston control with adaptive optics in stellar interferometry [PDF]
Astronomy & Astrophysics, 2001 The general purpose of an adaptive optics system is to correct for the wavefront corrugations due to atmospheric turbulence. When applied to a stellar interferometer, care must be taken in the control of the mean optical path length, commonly called differential piston.
C. Vérinaud, F. Cassaing
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Piston-Type Optical Modulator for Dynamic Thermal Radiation Tuning Applications [PDF]
Materials, 2021 This study introduces a movable piston-like structure that provides a simple and cost-effective avenue for dynamically tuning thermal radiation. This structure leverages two materials with dissimilar optical responses—graphite and aluminum—to modulate from a state of high reflectance to a state of high absorptance.
Andrew Caratenuto, Yi Zheng
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Dynamics of photon fluid flows driven by optical pistons [PDF]
Conference on Lasers and Electro-Optics, 2019 The piston problem, i.e. the dynamics of a uniform gas at rest under the action of a moving piston, is fundamental in shock wave physics [1,2]. In conservative systems, shock waves are regularized by the formation, owing to dispersion, of rapidly oscillating non-stationary structures, called dispersive shock waves (DSWs) [3–6].
Bendahmane, Abdelkrim +5 more
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Optical fiber analogous of the piston shock problem [PDF]
Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF), 2018 We investigate the optical analogous of the piston shock problem in gas dynamics. Using fast temporal measurements, we recorded dispersive shock waves formed by the propagation of a bi-chromatic photon fluid along an optical fiber.
Bendahmane, Abdelkrim +5 more
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Inducing dynamical bistability by reversible compression of an optical piston [PDF]
Physical Review E, 2015 We study the reversible crossover between stable and bistable phases of an overdamped Brownian bead inside an optical piston. The interaction potentials are solved developing a method based on Kramers's theory that exploits the statistical properties of the stochastic motion of the bead. We evaluate precisely the energy balance of the crossover.
Schnoering, Gabriel, Genet, Cyriaque
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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
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Optical-approximation analysis of sidewall-spacing effects on the force between two squares with parallel sidewalls [PDF]
, 2007 Using the ray-optics approximation, we analyze the Casimir force in a two dimensional domain formed by two metallic blocks adjacent to parallel metallic sidewalls, which are separated from the blocks by a finite distance h.
Jaffe, Robert L. +3 more
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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
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A Demonstration of Wavefront Sensing and Mirror Phasing from the Image Domain [PDF]
, 2014 In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the optical path,
Cheetham, Anthony +5 more
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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
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