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Long-Distance Electronic Speckle Pattern Interferometry
Optical Engineering, 1988Electronic speckle pattern interferometry has been used to measure the vibrations and deformations of objects located far from the optical head. Vibration recordings were made for a total path-length difference of up to 200 m with the object outdoors in bright sunshine. This limit was determined by practical considerations.
Ole J. Lokberg, Jan T. Malmo
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Electronic Speckle Pattern Interferometry of the Vibrating Larynx
Annals of Otology, Rhinology & Laryngology, 1995Laser holography is a technique that creates a three-dimensional image of a static object. This technique can be applied to the analysis of vibrating structures. Electronic speckle pattern interferometry uses a laser for illumination of the vibrating object and solid state detectors and digital hardware technology for capturing and processing the ...
G M, Gardner +3 more
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Vibration phase mapping using electronic speckle pattern interferometry
Applied Optics, 1976The contours of constant phases across sinusoidally vibrating objects have been mapped using reference wave phase modulation in time-average electronic speckle pattern interferometry.
O J, Løkberg, K, Høgmoen
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"Continuous" Pulsed Electronic Speckle Pattern Interferometry
SPIE Proceedings, 1987Holography and allied techliques such as electronic speckle pattern interferometry (ESPI) have the potential to provide the engineer with a powerful measuring technique. Why, therefore, is it not a technique readily available and widely used? Several arguments can be put forward; complexity, skill level, ease of use, in-situ capability, and ability to ...
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Infrared Electronic speckle pattern interferometry at 10 μm
SPIE Proceedings, 2007Demonstration of electronic speckle pattern interferometry of opaque scattering objects at 10 mm wavelength using a commercial thermal-camera is presented for the first time to our knowledge. The idea of using a wavelength longer than the usual visible ones is to render such holographic displacement measurement techniques less sensitive to external ...
Vandenrijt, Jean-François +1 more
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Synchronous Stroboscopic Electronic Speckle Pattern Interferometry
SPIE Proceedings, 1986Electronic Speckle Pattern Interferometry (E.S.P.I) oftenly called Electronic Holography is a practical powerful technique in non-destructive testing. Practical capabilities of the technique have been improved by fringe betterment and the control of analysis in the time domain, in particular, the scanning of the vibration cycle, with introduction of ...
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Speckle Pattern Interferometry Using Video Techniques
Optical Engineering, 1971Speckle pattern applications have grown up beside holography making use of the highly coherent illumination derived from optical lasers. Speckle has not been well understood and in many cases treated as noise and something to suppress as far as possible. To date a few workers have used speckle monitoring to detect surface stability and others have used
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Improvements on Electronic Speckle Pattern Interferometry
1987Fibre optics and synchronized amplitude and phase illuminating pulse modulation, controlled by microprocessor, are combined to improve performance and capabilities of measurements with E.S.P.I.. Cosmetic and resolution betterment of specklegrams is achieved while at the same time it is possible to design a portable and compact set-up, insensitive to ...
O. D. D. Soares +2 more
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Vibration measurement using phase-shifting speckle-pattern interferometry
Applied Optics, 1986Digital speckle-pattern interferometries for the measurement of a vibration amplitude are presented, based on phase shifting of a speckle interferogram. The calculation of the square root and division with phase-shifted speckle interferograms give a high contrast fringe pattern, which contours a vibration amplitude regardless of a bias deformation of ...
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Digital speckle pattern shearing interferometry: limitations and prospects
Applied Optics, 1991Since shearing interferometry, also called shearography, does not depict fringes caused by object tilt, it is a tool well suited for either nondestructive testing of objects under load or for quantitative evaluation of flexural strains. In traditional shearing interferometry, observation of fringes requires optical processing of doubleexposed ...
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