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Contouring by speckle interferometry
Optics Letters, 1985An optical method of generating high-constrast contours by using speckle interferometry has been proposed. To demonstrate the use of this technique the conventional dual-index immersion method has been adopted.
C, Joenathan, R K, Mohanty, R S, Sirohi
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Stellar speckle interferometry
Physics Bulletin, 1975Stellar speckle interferometry is a technique for obtaining diffraction-limited resolution of stellar objects despite the presence of the turbulent atmosphere which limits the resolution of conventional long-exposure pictures to approximately one arc second.
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Hololens in speckle and speckle shear interferometry
Applied Optics, 1985This paper presents a number of methods to obtain in-plane displacement, out of plane displacement and slope data using holographic optical elements. The results obtained with a hololens and a holoshear lens are as good as those obtained with conventional optical systems.
C, Joenathan, R K, Mohanty, R S, Sirohi
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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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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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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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Electronic speckle interferometry
ICALEO '88: Proceedings of the Optical Sensing and Measurement Conference, 1988Electronic Speckle Pattern Interferometry (ESPI) is becoming a very common test and measurement tool among industrial users. In its present form it rivals any current techniques for speed and ease of use. With improvements in image quality it has the potential to become the definitive tool for non-destructive testing.
Brad Sharp, Aaron Gara
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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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Electronic Speckle Pattern Interferometry
Topical Meeting on Holography, 1986Holographic workstations are now enabling the advantages of Holographic Interferometry (HI) to be taken outside research laboratories and placed alongside manufacturing equipment. Most rigidization problems have been overcome but two handicaps still limit its widespread application.
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Digital speckle-pattern shearing interferometry
Applied Optics, 1980An application of digital image processing techniques to speckle-shearing interferometry is described. A present system consists of an image-shearing camera using a Fresnel biprism of small angles and a digital TV-image processing facility. This interferometer makes it easy to measure in quasi-real-time spatial derivatives of surface displacement and ...
S, Nakadate, T, Yatagai, H, Saito
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