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Differential interferometry of γ-irradiated optical fibers
Applied Optics, 1980An interferometric method is discussed which enables changes in refractive index of irradiated optical fibers to be determined. The method was used to determine the changes of step-index fibers irradiated with 1 krad of gamma rays from a (60)Co source.
M, Bertolotti +3 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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Simulation of Differential Interferometry and Comparison with Experimental Results
1997This paper presents the computational simulation of a differential interferometer in a Mach-Zehnder arrangement with objects located outside the center of the interferometer. The computer simulation corresponds well to an experimental setup. This is illustrated for several basic phase objects. The theoretical models of these objects are discussed.
Rainer Wegenkittl, M. Eduard Gröller
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Electron density measurement by differential interferometry
Review of Scientific Instruments, 2006A novel differential interferometer is being developed to measure the electron density gradient and its fluctuations. Two separate laser beams with slight spatial offset and frequency difference are coupled into a single mixer making a heterodyne measurement of the phase difference which is <1% of the total phase change experienced by each beam ...
W. X. Ding +3 more
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Differential path considerations in optical stellar interferometry
Applied Optics, 1995A formulation of the differential-air-path problem for a large-baseline optical interferometer is presented. Because air is a dispersive medium, each wavelength has a different optical path length. This can be corrected to a large extent if an extra piece of glass is placed in each arm of the interferometer.
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Differential phase interferometry with the Keck telescopes
2004 IEEE Aerospace Conference Proceedings (IEEE Cat. No.04TH8720), 2005We summarize the differential phase (DP) technique as well as the planned implementation at the Keck interferometer. Multicolor phase measurements are potentially a powerful astrophysical probe - and can allow ground-based direct detection of extrasolar planets.
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Single-shot tomography by differential interferometry
Measurement Science and Technology, 1995Presents a new interferometric measurement technique which makes it possible to determine the spatial refractive index distribution inside asymmetrical transparent objects. The suggested set-up, consisting of mirror galleries for producing several projections, a holographic beam coupling system including a method for suppressing possible object self ...
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Observational Techniques Related to Differential Interferometry
1975The combination of the basic principle of differential interferometry with additional optical components and systems leads to a variety of observational techniques. A classification of these techniques is given. With the different systems recording of the optical path modulation φ (x,y) by a phase object and any of its first and second derivatives in ...
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