Results 131 to 140 of about 1,567 (171)
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Phase separation and droplet nucleation induced by an optical piston
Physical Review E, 1994no ...
Delville, J. P. +3 more
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Optical Piston Temperature in an internal combustion engine
SAE International Journal of Engines, 2011In the last ten year the mechanical power output of car engine increased significantly. This result has been possible especially through new injection systems that brought to an optimization of the combustion (direct injection, common rail) and to an improvement of the turbo charging.
SENATORE, ADOLFO +2 more
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The optical piston in a capillary cell with open ends
Journal of Physics B: Atomic, Molecular and Optical Physics, 1988The authors present measurements of the time evolution of the spatial density distribution of Na atoms in an argon buffer gas, inside a capillary cell with open ends. The entrance of the capillary is irradiated with a laser beam that fills its cross section, so that light-induced drift occurs. For sufficiently high intensity, a steep front may build up,
H G C Werij, G Nienhuis, J P Woerdman
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Dynamics of the Optical Piston
1985Recently we have demonstrated a semipermeable optical piston [1] using the principle of light-induced drift (LID) [2]. In the present work,new experimental results on the dynamics of the optical piston are reported and compared with theory. The basic idea of LID and the optical piston is as follows.
H. G. C. Werij +4 more
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Fizeau beam-combination for optical astronomy: piston retrieval
SPIE Proceedings, 2003The field of view for the first generation VLTI instruments (VINCI, MIDI, AMBER etc.) is limited to the diffraction limited beam of a single telescope (for a 8.2-meter telescope at 2-micron this is 0.6 arcseconds). However, the VLTI infrastructure with its main delay lines, transfers a 2 arcseconds beam from the telescopes to the interferometric ...
Eric J. Bakker, Rudolf S. Le Poole
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Piston alignment of segmented optical mirrors via convolutional neural networks
Optics Letters, 2018Most of the methods used today for the alignment of segmented mirrors are based on Shack-Hartman wavefront sensors. Other proposed methods are based on curvature sensors. These can be used to cross-check the measurements given by the primary method. We investigate a different approach which employs convolutional neural networks.
Dailos, Guerra-Ramos +3 more
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Modeling of the optical piston: Density-wave shape and resonance-fluorescence effects
Physical Review A, 1988We present results of a numerical model of the optical piston driven by laser-induced drift (LID). The model is based on a drift-velocity formulation of Lawandy, derived from an asymmetric-random-walk argument, and includes resonance-fluorescence effects. The model is applied primarily to the experimental conditions of H. G. C.
, Calo, , Lawandy, , Frezzo, , Perkins
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A piston error detection method of optical synthetic aperture system
SPIE Proceedings, 2014The existence of phase error influences the imaging performance of optical synthetic aperture system and limits the resolution of the imaging system. The relationship between point spread function of binocular system and piston error is analyzed and the conclusion that the relation between point spread function and piston error is irrational with ...
Xiaofeng Wei +3 more
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Analysis of piston error of an optical sparse-aperture imaging system
SPIE Proceedings, 2009With the development of Earth and Space missions, the quest for higher spatial resolution for telescopes will turn into urgent need. Optical sparse-aperture system can be designed to obtain high resolution in astronomical object imaging with several independent small-aperture telescopes.
Juan Zhao +5 more
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Coupled waveguide integrated optic segment piston sensor for the GMT
2013 Conference on Lasers & Electro-Optics Europe & International Quantum Electronics Conference CLEO EUROPE/IQEC, 2013Integrated optic segment piston sensor (IOPS) for the Giant Magellan Telescope (GMT) uses single mode laser written waveguides to measure segment piston (axial alignment) of the GMT primary mirrors. Light in the H-band (from 1.5 to 1.6 μm) incident on each segment originating from an off-axis guide star is coupled into separate laser written single ...
Francis Bennet +5 more
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