Results 221 to 230 of about 20,096 (267)

Fringe scanning speckle-pattern interferometry

Applied Optics, 1985
Digital speckle-pattern interferometry systems for automatic measurement of deformations of a diffuse object are presented, which are based on a fringe scanning method with phase-shifted speckle interferograms. A digital speckle pattern before deformation of an object is recorded in the mass storage device of a computer facility.
S, Nakadate, H, Saito
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Speckle interferometry in transparent media

Applied Optics, 1986
Speckle interferometry is applied to transparent media to obtain measurements of full-field density variations. Speckle interferometry can present decreased vibration sensitivity compared to some wave front comparison methods while maintaining high sensitivity.
D D, Verhoeven, P V, Farrell
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Speckle photography combined with speckle interferometry

Optics and Lasers in Engineering, 2004
By combining speckle interferometry (SI) measurements with speckle photography, the fringe visibility can be kept high despite the presence of a large bulk or rotating motion of the object. This combined technique improves the usability and measuring range of both pulsed and phase-stepped SI-methods. This paper reviews the theory of fringe formation in
N.-E. Molin, M. Sjödahl, P. Gren, A. Svanbro   +3 more
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Computer-aided speckle pattern interferometry

Applied Optics, 1983
An on-line computer system for measuring the deformation of a diffuse object with a speckle interferometer is presented. Methods for evaluating a speckle interferogram using digital image processing techniques are also discussed. The system consists of an interferometric optical setup and a computer-TV image processing facility. A speckle interferogram
S, Nakadate, T, Yatagai, H, Saito
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Differential Speckle Interferometry

Optica Acta: International Journal of Optics, 1982
This paper describes an experiment in narrow spectral band speckle interferometry, which uses variations in the spectrum across the astronomical object under study, to obtain information of the object on the millisecond of arc scale. We plan to apply this experiment to the study of spectroscopic double stars, stellar rotation, spectroscopic and ...
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High speed speckle interferometry

SPIE Proceedings, 2006
The basic optical set-ups used for speckle interferometry have a limited capability to study transient events due to the synchronization with the acquisition devices. This capability is explored in this work and compared with recent developed techniques such as the temporal phase unwrapping.
A. Davila, V. Pinto, G. Garnica
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Astronomical Speckle Interferometry

Joint Topical Meeting on Information Processing in Astronomy and Optics, 1983
Antoine Labeyrie first pointed out in 1970 that short exposure pictures of astronomical objects can be analyzed in a simple way to recover information about the objects' structures down to the diffraction limit of a telescope. Labeyrie's method, which rather quickly came to be called speckle interferometry, takes advantage of the convolution theorem to
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Measuring Microvibrations by Heterodyne Speckle Interferometry

Optics Letters, 1981
In-plane as well as out-of-plane displacements and vibrations of objects with diffusely scattering surfaces are measured in real time. Microvibrations with amplitudes down to 1 nm and frequencies up to 5 MHz were analyzed at a spatial resolution of 35microm.
R, Dändliker, J F, Willemin
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IV Speckle Interferometry

1978
Publisher Summary This chapter discusses the nature of the speckle pattern and defines some of its basic characteristics. The speckle effect in optics is the generation of a random intensity pattern formed when coherent light is scattered by a rough surface or is diffused by a medium containing scattering centers.
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Elementary Speckle Interferometry

2012
International ...
Jacquot, Pierre, Slangen, Pierre, Borza, Dan   +2 more
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