Results 11 to 20 of about 16,225 (252)
Spatial Spectrum Analysis of Wave-Front Correction with a Segmented Mirror [PDF]
, 2003 An expression is derived for the spatial power spectrum of wave-front errors after correction with a segmented mirror. This includes estimates of the spectral contributions of segment piston and tilt corrections and spatial aliasing by a regular array of
Padin, Stephen
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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
Tests with a Carlina-type diluted telescope; Primary coherencing [PDF]
, 2012 Studies are under way to propose a new generation of post-VLTI interferometers. The Carlina concept studied at the Haute- Provence Observatory is one of the proposed solutions. It consists in an optical interferometer configured like a diluted version of
A. Le Vansuu +37 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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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
core +2 more sources
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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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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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
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