Results 201 to 210 of about 16,325 (263)

Optical piston in rubidium

Optics Communications, 1987
Abstract We report observation of an optical piston due to the effect of light induced drift in a rubidium-argon mixture. A tunable semiconductor diode laser is used for diagnostics of rubidium density and isotropic ratio. Sign and magnitude of the light induced drift effect depend directly on fine and hyperfine structure of rubidium.
W.A. Hamel, A.D. Streater, J.P. Woerdman
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Thermo-optical piston in gases

AIP Conference Proceedings, 2014
The new steady state of the gas – thermo-optical pressure difference is considered. This condition occurs in the gas that is in a closed capillary in the field of resonant laser radiation and a temperature gradient. The pressure difference at the ends of the capillary is determined by the interaction of three fluxes – thermal creep, the light-induced ...
I. V. Chermyaninov, V. G. Chernyak
openaire   +1 more source

Adaptive optics for array telescopes using piston-and-tilt wave-front sensing

Applied Optics, 1992
A near-infrared adaptive optics system operating at approximately 50 Hz has been used to control phase errors adaptively between two mirrors of the Multiple Mirror Telescope by stabilizing the position of the interference fringe in the combined unresolved far-field image.
Peter Wizinowich, B. A. McLeod, Michael Lloyd‐Hart, J. R. P. Angel, D. Colucci, R. Dekany, Donald McCarthy, David Wittman, Ian Scott‐Fleming   +8 more
openalex   +3 more sources

MEMS mirror with tip or piston motion for use in adaptive optics

The Journal of the Acoustical Society of America, 2008
An array of high fill factor mirrors has each mirror be coupled across two deformable spring bars that are deformed using a drive. The two deformable springs are parallel to each other, and coupled together, e.g., by a cross bar. A support is coupled at one end to the cross bar and at its opposite end to the mirror. Coupled across the deformable spring
Dennis S. Greywall
openalex   +2 more sources

Wide-range, high-accuracy, white light piston sensor for segmented optics

Optical Engineering, 1995
Optical systems with segmented mirrors require precision coalignment of their segments to attain the desired performance. A novel sensor for measuring piston over a ± 10 wave range by analyzing the image of a white light point source is described. The sensor combines a Young's two-slit aperture pair for coarse sensing with another set of apertures ...
Alan Wertheimer
openalex   +2 more sources

<title>High-accuracy white-light optical piston sensor for segmented optics</title>

SPIE Proceedings, 1993
Alan Wertheimer, Thomas W. Dey
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Phase separation and droplet nucleation induced by an optical piston

Physical Review E, 1994
no ...
Delville, J. P., Lalaude, C., Freysz, E., Ducasse, A.   +3 more
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Optical Piston Temperature in an internal combustion engine

SAE International Journal of Engines, 2011
In 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, BUONO, DARIO, E. Iarrobino   +2 more
openaire   +3 more sources

Fizeau beam-combination for optical astronomy: piston retrieval

SPIE Proceedings, 2003
The 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
openaire   +1 more source

Dynamics of the Optical Piston

1985
Recently 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, J. E. M. Haverkort, W. A. Hamel, R. W. M. Hoogeveen, J. P. Woerdman   +4 more
openaire   +1 more source