The laser speckle interferometry results are in agreement with strain gage results at strain rates up to .1sec for temperatures up to 250 deg F. This investigation also indicated laser speckle interferometry would be an excellent noncontact localized strain measuring device for adverse conditions if the following drawbacks were overcome.

A single beam electronic speckle pattern interferometer (ESPI) system that can be compensated for small rigid body motions of the test sample using 3 linearly independent displacement maps is

To optimise the parameters of a laser beam, a focusing system, and a photodetector, it is necessary to have information on the basic parameters of the speckle pattern. A method is proposed whereby the spatial speckles created in front of a plate with an optically rough surface when illuminated by a coherent laser beam is used to generate slope contour fringes. This is done by photographing the speckles contained in a parallel plane in front of the plate before and after deformation via double exposure. The resulting speckle interferogram is then optically Scientists from the Getty Conservation Institute have developed a non-invasive method for detecting voids behind the surface of wall paintings, plasters and Stellar Speckle Interferometry • Atmosphere limits resolution to approximately 1 arc second (10 cm aperture) • Image of star shows speckles if – Exposure time less than period of atmospheric turbulence (1 msec) – Spectral bandwidth small (10 nm) so coherence length long • Speckle size determined by wavelength and Speckle interferometry describes the two-step process of generating such a map. In speckle photography, a double exposure records the speckle pattern produced by the object in two separate states. Optical processing of this `specklegram` produces a final interferogram with contours that can be used to determine surface displacement.

Speckle Interferometry a Rough Surface with Laser Radiation. Optics 505 - James C. Wyant Page 2 Optics 505 - James C. Wyant Chapter 18 Page 3 of 15 Laser Speckle interferometry: theory and applications Maria L. Calvo Department of Optics, ComplutenseUniversity of Madrid 17thFebruary 2017, 11:00 Leonardo Building ‐BudinichLecture Hall Winter College on Optics 2017: Advanced Optical Techniques for Bio‐imaging. 13‐24 February 2017 1 A method is proposed whereby the spatial speckles created in front of a plate with an optically rough surface when illuminated by a coherent laser beam is used to generate slope contour fringes. This is done by photographing the speckles contained in a parallel plane in front of the plate before and after deformation via double exposure. A method is proposed whereby the spatial speckles created in front of a plate with an optically rough surface when illuminated by a coherent laser beam is used to generate slope contour fringes. This is done by photographing the speckles contained in a parallel plane in front of the plate before and after deformation via double exposure. The resulting speckle interferogram is then optically Speckle interferometry In 1970, the French astronomer Antoine Labeyrie showed that Fourier analysis (speckle interferometry) can obtain information about the high-resolution structure of the object from the statistical properties of the speckle patterns.

As opposed to classical interferometry where optically smooth surfaces are studied and no speckle pattern appears, speckle interferometry uses the phase information carried by the speckles to determine the deformation of the object.

The creation of laser and discovery of the speckle structure of scattered radiation were immediately followed by a number of theoretical papers on statistical

These techniques can be usefully applied in the field of Historical and Cultural Heritage conservation, for reconstruction of 3D structure of the object under observation and its deformation under stress. Speckle interference patterns need in any case a kind of further decoding step in order to become a source of useful information. Thus, while ‘classical interferometry’ (CI) is the unanimously accepted designation for smooth wave interferometry, it could be natural to term ‘SI’ all types of interferences involving speckle waves. 1979-07-01 Electronic Speckle Pattern interferometry (ESPI) is a non-destructive optical method for studying surface deformations.

In this work, an X-ray nanobeam of a free-electron laser was generated using reflective KB focusing optics combined with speckle interferometry. The speckle profiles generated by 2 nm platinum particles were systematically investigated on a single-shot basis by changing the alignment of the multilayer KB mirror system installed at the SPring-8 Angstrom Compact Free-Electron Laser, in combination with …

Laser Interferometry and Holography are well-established, highly sensitive techniques for non-destructive testing and analysis. These techniques can be usefully applied in the field of Historical and Cultural Heritage conservation, for reconstruction of 3D structure of the object under observation and its deformation under stress. In this work, an X-ray nanobeam of a free-electron laser was generated using reflective KB focusing optics combined with speckle interferometry. The speckle profiles generated by 2 nm platinum particles were systematically investigated on a single-shot basis by changing the alignment of the multilayer KB mirror system installed at the SPring-8 the focused beam. In this work, an X-ray nanobeam of a free-electron laser was generated using reﬂective KB focusing optics combined with speckle interferometry. The speckle proﬁles generated by 2 nm platinum particles were systematically investigated on a single-shot basis by changing the alignment of The principal speckle interferometry techniques are ESPI (electronic speckle pattern interferometry) and shearography. Schematic illustrations of typical optical arrangements for the two techniques are shown in figure 2.

Stereoscopic digital speckle photography · 2.
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While microscopic deformations are determined by a combination of Digital Holographic Interferometry (DHI) and Digital Speckle Photography (DSP), macroscopic 3D shape, 2017-01-13 · Student speckle interferometry research program - Duration: 19:36. cleo991 315 views A metrology system combining three laser speckle measurement techniques for simultaneous determination of 3D shape and micro- and macroscopic deformations is presented. While microscopic deformations are determined by a combination of Digital Holographic Interferometry (DHI) and Digital Speckle Phot … This month we are featuring two Technology Applications articles: 1) Full-field Dynamic Displacement and Strain Measurement Using Advanced 3D Photogrammetry; and 2) Residual Stress Measurement Using the Hole Drilling Method and Laser Speckle Interferometry.
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A further field of research, yielding some surprisingly interesting results, is laser speckle photography (Sect. 6.6), which although having no exact counterpart in conventional interferometry

measurement based on the laser speckle phenomenon has now become an important subject of optical metrology for full-field NDE (Non destructive Evaluation).The speckle techniques can be classified into three broad categories: speckle photography, speckle interferometry and speckle shear interferometry. Optotune laser speckle reducers remove local interferences and significantly reduce speckle noise in laser systems by dynamically diffusing the laser beam.

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Carlsson, Speckle interferometry for measurement of continuous deformation, accepted for publication in. Optics and Lasers in Engineering (2002). 7. Wei An,

We performed experimental evaluation of various positions (ear, paw, and tail) of the of dynamic light scattering sensor of near-infrared laser radiation (840 nm) using speckle interferometry in rats.

A dual scanning laser speckle interferometry experiment was designed to observe the dynamic behavior of the magnetic fluid actuated by a magnetic field.

Se hela listan på de.wikipedia.org 1979-07-01 · Strain analysis by one-beam laser speckle interferometry. 2: Multiaperture method. Chiang FD, Khetan RP. A detailed analysis of using multiple apertures to record laser speckles for strain analysis is presented.

(1) The output of the laser can be divided in order to form, on the one hand, a single illumination-. A noninvasive and noncontact technique based on the principle of laser speckle interferometry has been developed to record the cardiac displacements 00001sec to .1sec, temperatures up to 250 deg F and heating rates of 250 deg Fsec. Strain was measured by laser speckle interferometry technique and strain May 1, 2017 laser speckle based methods to form a new hybrid deformation Digital Image Correlation (DIC) and laser speckles interferometry was Aug 30, 2019 holographic interferometry (HI) [8], digital speckle pattern the illumination of the samples using a solid-state laser beam. (532.8nm, 0-2.5W). Feb 21, 2020 Based on LabVIEW, this paper establishes a laser speckle interferometry experimental platform for precise automatic timing control and speckle pattern interferometry(ESPI) systems for displacement and strain measurements have assuming the laser source and CCD camera are located in. Optics and Lasers in Engineering 40 (2003) 439–445.