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Optics Letters, 2019
In the cophasing of the segmented optical mirrors, the Shack-Hartmann wavefront sensor is not sensitive to the submirror piston error and the large range piston errors beyond the cophasing detection range of phase diversity algorithm.
Dequan Li, Shuyan Xu, Dong Wang, D. Yan
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In the cophasing of the segmented optical mirrors, the Shack-Hartmann wavefront sensor is not sensitive to the submirror piston error and the large range piston errors beyond the cophasing detection range of phase diversity algorithm.
Dequan Li, Shuyan Xu, Dong Wang, D. Yan
semanticscholar +1 more source
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 ...
Xiao-feng Wei +3 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 ...
Brady Espeland +5 more
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A Tip-Tilt-Piston Micromirror Array for Optical Phased Array Applications
Journal of Microelectromechanical Systems, 2010A tip-tilt-piston micromirror array based on electrothermal bimorph actuation is presented. The micromirror uses a compactly folded actuator design that can realize high fill-factor with a simple fabrication process. A 4 × 4 micromirror array with sub-apertures of 0.9 mm and a fill-factor of 54% is demonstrated.
Edward A. Watson +4 more
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MEMS tip/tilt and piston mirror arrays as diffractive optical elements
SPIE Proceedings, 2005We present an analytic evaluation of the optical performance of a tip/tilt and piston Spatial Light Modulator, for use in adaptive optic and beam steering applications. The impact of array fill factor, pixel curvature, position and tilt accuracy, and pixel yield are discussed in detail.
Clinton Randy Giles +2 more
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Two Dimensional MEMS Piston Array for DUV Optical Pattern Generation
IEEE/LEOS International Conference on Optical MEMS and Their Applications Conference, 2006., 2006We describe the design, fabrication and dynamics of a two dimensional array of MEMS piston mirrors that fulfil the requirements needed to modulate deep ultraviolet radiation for mask pattern ...
F.P. Klemens +15 more
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Adaptive optics correction of scintillation in underwater medium
, 2020Adaptive optics correction of the scintillation index of a Gaussian laser beam in underwater turbulence is studied. To introduce the adaptive optics correction, filter functions providing the piston, tilt and astigmatism effects are adapted to promote ...
Y. Baykal
semanticscholar +1 more source
The Journal of the Acoustical Society of America, 2000
The transfer function of a fiber-optic hydrophone (FOH) is computed for various fiber core radii. The hydrophone is modeled as a rigid disk, with plane waves impinging at normal or oblique incidence. The total sound field is written as the sum of the incident field and the field diffracted from the hydrophone.
Hans-Georg Trier +5 more
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The transfer function of a fiber-optic hydrophone (FOH) is computed for various fiber core radii. The hydrophone is modeled as a rigid disk, with plane waves impinging at normal or oblique incidence. The total sound field is written as the sum of the incident field and the field diffracted from the hydrophone.
Hans-Georg Trier +5 more
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Thermal piston model for the optoacoustic effect: Sound generation in an optically thick gas
Applied Physics Letters, 1987At high concentrations of an infrared absorbing gas, the optical absorption length for the incident radiation can become small compared with the thermal diffusion length in the gas. A description of the optoacoustic effect consequently must include thermal conduction of heat to the cell window since sound generation takes place in a thin layer of gas ...
R. B. Stewart, Gerald J. Diebold
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Simultaneous piston and tip-tilt measurement of segmented optics with cross-fringe phasing sensor
, 2023 Seichi Sato, Tadahito Mizutani
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