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Effect Of Piston And Tilt Bias Errors In Multiple Wavefront Interference
Optical Engineering, 1989The impact of tilt bias errors in multiple wavefront interferometry is assessed in terms of its effect on the ability to determine piston phase differences between wavefronts from such interferometry. The error in such piston phase determination due to tilt bias has been found to be substantial.
Petras V. Avizonis +2 more
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Finite difference nearfield errors for a baffled vibrating piston
The Journal of the Acoustical Society of America, 1984Two-microphone finite difference errors for velocity, intensity, and radiated power were analyzed in the near- and farfield of a vibrating piston in a baffle. Since a closed form solution is not available for nearfield radiation, numerical solutions were used to obtain the sound pressure, velocity, and intensity.
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Journal of the Optical Society of America A, 1985
The purpose of this paper is to develop relationships between the normalized far-field peak intensity (Strehl ratio) and system perturbations, such as mirror misfigure, piston errors, jitter, and polarization errors, for phased-array transmitters. Some of these sources of degradation are unique to phased arrays, whereas others are shared in common with
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The purpose of this paper is to develop relationships between the normalized far-field peak intensity (Strehl ratio) and system perturbations, such as mirror misfigure, piston errors, jitter, and polarization errors, for phased-array transmitters. Some of these sources of degradation are unique to phased arrays, whereas others are shared in common with
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Efficient method for the reduction of large piston errors in segmented-mirror telescopes
SPIE Proceedings, 2004Phase discontinuity sensing (PDS) is one of two successful approaches to segment phasing that are currently in use at the Keck telescopes, but it has only a limited capture range. We describe and present numerical simulations of a broadband version of the current (narrowband) PDS algorithm that can extend the capture range from 0.4 to 40 microns.
Gary, Chanan, Agustí, Pintó
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ESTIMATION OF STAPES PISTON MOTION WITH UNI-DIRECTIONAL MEASUREMENTS IS PRONE TO ERROR
Middle Ear Mechanics in Research and Otology, 2007Abstract: In most experiments, access for direct measurement of stapes motion in line with the piston axis is not available and piston motion is estimated from single component interferometric measurements done under observation directions that make angles up to 60 degrees with the piston axis.
Decraemer, Willem +5 more
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Estimation of the GMT inter-segment piston error from deformable mirror commands
SPIE Proceedings, 2011ABSTRACT The Giant Magellan Telescope (GMT) will place seven prim ary mirror segments of 8.4 m diameter on a common mount to form a single co-phased aperture of 25 m. 1 High order adaptive optics (AO) using an adaptive secondary mirror that is segmented in the same way as the primary will correct the telescopes imaging to the diffraction limit in the ...
Michael Hart +5 more
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Experimental determination of errors in piston manometers at high pressures
Measurement Techniques, 1959The suggested method of comparing piston manometers of high pressures by means of a differential instrument is also applicable for determining experimentally the differences between the errors as functions of pressure. The experiments carried out up to pressures of 7000 kg/cm2 confirmed the previously obtained formulas of corrections for strains in ...
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Research of Kinematic and Dynamic Errors of Crank-Piston Mechanisms
2016The issue of determination of errors and precision of mechanisms and machines always presents an important problem. This problem is rather urgent in machine building, agriculture machinery, food industry, instrument engineelink and other fields of industry.
Nodar Davitashvili, Valeh Bakhshaliev
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Tolerance Analysis for Piston and Tilt Error in Hexagonal Laser Phased Array
2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), 2019Coherent Beam Combining is an alternative approach to the construction of high-power lasers, which mitigates the thermo-optic problems occurring in the classic laser construction [1]. However, phased array requires the control of a larger number of parameters, which results in easier beam quality degradation.
Przemyslaw Gontar, Jan K. Jabczynski
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Diagnosing piston error from hyperspectral image with extended scene
Optics and Lasers in Engineering, 2023Yang Li, Shengqian Wang
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