Results 211 to 220 of about 168,541 (274)
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Spectral Speckle Interferometry
Astrophysics and Space Science, 1989A method of obtaining an objective prism spectrum of a stellar object with diffraction-limited spatial resolution is described.
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Characterization of bones by speckle interferometry
Journal of Medical Engineering & Technology, 2003Speckle photography interferometry (SPI) is used to evaluate the stress-strain behaviour of animal bones under loads by recording the speckle fields generated on the bone surface and thus finding the relationship between the fractal dimension D(s) and the compression load P. The procedure consists of application of slow and monotonous compression loads,
J, Horta +3 more
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Materials Testing, 1996
With the electronic laser speckle interferometry (ESPI) it is possible to make deformation and strain fields visible. An easy to use sensor is presented. For demonstration the inhomogeneous deformation behaviour of laser-welded aluminium sheet is shown. At lower load the deformation is homogeneous, at higher load there is a deformation concentration in
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With the electronic laser speckle interferometry (ESPI) it is possible to make deformation and strain fields visible. An easy to use sensor is presented. For demonstration the inhomogeneous deformation behaviour of laser-welded aluminium sheet is shown. At lower load the deformation is homogeneous, at higher load there is a deformation concentration in
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SPIE Proceedings, 1985
The atmosphere of the earth restricts the resolution of conventional astrophotography to about 1". We will discuss various high-resolution speckle methods which can overcome image degradation caused by the atmosphere and telescope aberrations. All methods yield diffraction-limited resolution, for example 0.03" for a 3.6m telescope. We will show various
G. Weigelt +5 more
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The atmosphere of the earth restricts the resolution of conventional astrophotography to about 1". We will discuss various high-resolution speckle methods which can overcome image degradation caused by the atmosphere and telescope aberrations. All methods yield diffraction-limited resolution, for example 0.03" for a 3.6m telescope. We will show various
G. Weigelt +5 more
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Fast phase denoising using stationary wavelet transform in speckle pattern interferometry
Measurement science and technology, 2019Phase fringe patterns in speckle pattern interferometry need to be denoised before they are processed further to ensure phase unwrapping reliability and phase determination accuracy.
Xue Ning +4 more
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Speckle Interferometry And Differential Speckle Interferometry Using Cross-Spectrum Techniques
Optical Engineering, 1986A cross-spectrum analysis technique that makes it possible to compute an unbiased estimate of the speckle pattern Wiener spectrum has been developed at the University of Nice. Using a one-dimensional interferometer, the technique has given results on several subjects such as the study of atmospheric modulation transfer function, including anisotropy ...
Claude Aime +4 more
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Applied Optics, 2019
Digital speckle pattern interferometry and digital shearography are widely used in nondestructive testing due to their advantages of high speed, full field, and high sensitivity.
Qihan Zhao +5 more
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Digital speckle pattern interferometry and digital shearography are widely used in nondestructive testing due to their advantages of high speed, full field, and high sensitivity.
Qihan Zhao +5 more
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Interferometry with a Speckle Carrier
Journal of Modern Optics, 1989Abstract The interferometric properties of two types of images are investigated. One image is formed by conventional holographic interferometry, the other using a speckle carrier technique. The second process employs a diffuse reference beam, with the spherical carrier being replaced by a speckle carrier in the register state.
J.M. Simon, H. Barnils
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Measuring Microvibrations by Heterodyne Speckle Interferometry
Optics Letters, 1981In-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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Application of digital shearing speckle pattern interferometry for thermal stress
Measurement, 2018A thermal stress measuring method based on the digital shearing speckle pattern interferometry (DSSPI) is proposed in this paper. The concept of the method is that the thermal inequality leading to the deformation of the object surface will be recorded ...
Xu Wang +8 more
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