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Title: On-line surveillance of a dynamic process by a moving system based on pulsed digital holographic interferometry

Abstract

A method based on pulsed digital holographic interferometry for the measurement of dynamic deformations of a surface by using a moving system is presented. The measuring system may move with a speed of several meters per minute and can measure deformation of the surface with an accuracy of better than 50 nm. The deformation is obtained by comparison of the wavefronts recorded at different times with different laser pulses produced by a Nd:YAG laser. The effect due to the movement of the measuring system is compensated for by digital processing of the different holograms. The system is well suited for on-line surveillance of a dynamic process such as laser welding and friction stir welding. Experimental results are presented, and the advantages of the method are discussed.

Authors:
; ; ;
Publication Date:
OSTI Identifier:
20779269
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Optics; Journal Volume: 45; Journal Issue: 5; Other Information: DOI: 10.1364/AO.45.000935; (c) 2006 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DEFORMATION; FRICTION; HOLOGRAPHY; INTERFEROMETRY; LASER WELDING; LASERS; MEASURING METHODS; SURFACES

Citation Formats

Pedrini, Giancarlo, Alexeenko, Igor, Osten, Wolfgang, and Schnars, Ulf. On-line surveillance of a dynamic process by a moving system based on pulsed digital holographic interferometry. United States: N. p., 2006. Web. doi:10.1364/AO.45.0.
Pedrini, Giancarlo, Alexeenko, Igor, Osten, Wolfgang, & Schnars, Ulf. On-line surveillance of a dynamic process by a moving system based on pulsed digital holographic interferometry. United States. doi:10.1364/AO.45.0.
Pedrini, Giancarlo, Alexeenko, Igor, Osten, Wolfgang, and Schnars, Ulf. Fri . "On-line surveillance of a dynamic process by a moving system based on pulsed digital holographic interferometry". United States. doi:10.1364/AO.45.0.
@article{osti_20779269,
title = {On-line surveillance of a dynamic process by a moving system based on pulsed digital holographic interferometry},
author = {Pedrini, Giancarlo and Alexeenko, Igor and Osten, Wolfgang and Schnars, Ulf},
abstractNote = {A method based on pulsed digital holographic interferometry for the measurement of dynamic deformations of a surface by using a moving system is presented. The measuring system may move with a speed of several meters per minute and can measure deformation of the surface with an accuracy of better than 50 nm. The deformation is obtained by comparison of the wavefronts recorded at different times with different laser pulses produced by a Nd:YAG laser. The effect due to the movement of the measuring system is compensated for by digital processing of the different holograms. The system is well suited for on-line surveillance of a dynamic process such as laser welding and friction stir welding. Experimental results are presented, and the advantages of the method are discussed.},
doi = {10.1364/AO.45.0},
journal = {Applied Optics},
number = 5,
volume = 45,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2006},
month = {Fri Feb 10 00:00:00 EST 2006}
}
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