Lockin-Interferometry: Principle and Applications in NDE

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Izvoz citacije: ABNT
MENNER, Philipp ;GERHARD, Henry ;BUSSE, Gerd .
Lockin-Interferometry: Principle and Applications in NDE. 
Strojniški vestnik - Journal of Mechanical Engineering, [S.l.], v. 57, n.3, p. 183-191, june 2018. 
ISSN 0039-2480.
Available at: <https://www.sv-jme.eu/sl/article/lockin-interferometry-principle-and-applications-in-nde/>. Date accessed: 23 jan. 2021. 
doi:http://dx.doi.org/10.5545/sv-jme.2010.169.
Menner, P., Gerhard, H., & Busse, G.
(2011).
Lockin-Interferometry: Principle and Applications in NDE.
Strojniški vestnik - Journal of Mechanical Engineering, 57(3), 183-191.
doi:http://dx.doi.org/10.5545/sv-jme.2010.169
@article{sv-jmesv-jme.2010.169,
	author = {Philipp  Menner and Henry  Gerhard and Gerd  Busse},
	title = {Lockin-Interferometry: Principle and Applications in NDE},
	journal = {Strojniški vestnik - Journal of Mechanical Engineering},
	volume = {57},
	number = {3},
	year = {2011},
	keywords = {Lockin-ESPI; Lockin-Shearography; defect-selective imaging; interferometric depth profiling},
	abstract = {Interferometry is relevant for non-destructive evaluation (NDE) since dimensional changes much smaller than an optical wavelength result in detectable signals. Fringe images obtained with Electronic-Speckle-Pattern-Interferometry (ESPI) or shearography display changes of surface topography between two states of an object, usually using a static load. Usually, hidden defects are found by comparing the observed fringe pattern to the one obtained on an intact reference component and to attribute observed differences to a defect. Our approach is a periodical object illumination with light that is absorbed in the surface to generate heat and a corresponding modulation of thermal expansion. At the same time fringe images are recorded (either with ESPI or shearography) to give a stack. Subsequently, each image is unwrapped and thereafter the time-dependent content of each pixel is Fourier transformed at the excitation frequency, so the result is local amplitude and phase of the modulated response at this frequency. The phase image displays local delay between excitation and response. This phase change depends on the depth where the defect is located since thermal waves are involved. In this paper, NDE-examples obtained using this new technique are presented. It is also shown how the achieved improvement as compared to conventional interferometry is up to an order of magnitude.},
	issn = {0039-2480},	pages = {183-191},	doi = {10.5545/sv-jme.2010.169},
	url = {https://www.sv-jme.eu/sl/article/lockin-interferometry-principle-and-applications-in-nde/}
}
Menner, P.,Gerhard, H.,Busse, G.
2011 June 57. Lockin-Interferometry: Principle and Applications in NDE. Strojniški vestnik - Journal of Mechanical Engineering. [Online] 57:3
%A Menner, Philipp 
%A Gerhard, Henry 
%A Busse, Gerd 
%D 2011
%T Lockin-Interferometry: Principle and Applications in NDE
%B 2011
%9 Lockin-ESPI; Lockin-Shearography; defect-selective imaging; interferometric depth profiling
%! Lockin-Interferometry: Principle and Applications in NDE
%K Lockin-ESPI; Lockin-Shearography; defect-selective imaging; interferometric depth profiling
%X Interferometry is relevant for non-destructive evaluation (NDE) since dimensional changes much smaller than an optical wavelength result in detectable signals. Fringe images obtained with Electronic-Speckle-Pattern-Interferometry (ESPI) or shearography display changes of surface topography between two states of an object, usually using a static load. Usually, hidden defects are found by comparing the observed fringe pattern to the one obtained on an intact reference component and to attribute observed differences to a defect. Our approach is a periodical object illumination with light that is absorbed in the surface to generate heat and a corresponding modulation of thermal expansion. At the same time fringe images are recorded (either with ESPI or shearography) to give a stack. Subsequently, each image is unwrapped and thereafter the time-dependent content of each pixel is Fourier transformed at the excitation frequency, so the result is local amplitude and phase of the modulated response at this frequency. The phase image displays local delay between excitation and response. This phase change depends on the depth where the defect is located since thermal waves are involved. In this paper, NDE-examples obtained using this new technique are presented. It is also shown how the achieved improvement as compared to conventional interferometry is up to an order of magnitude.
%U https://www.sv-jme.eu/sl/article/lockin-interferometry-principle-and-applications-in-nde/
%0 Journal Article
%R 10.5545/sv-jme.2010.169
%& 183
%P 9
%J Strojniški vestnik - Journal of Mechanical Engineering
%V 57
%N 3
%@ 0039-2480
%8 2018-06-28
%7 2018-06-28
Menner, Philipp, Henry  Gerhard, & Gerd  Busse.
"Lockin-Interferometry: Principle and Applications in NDE." Strojniški vestnik - Journal of Mechanical Engineering [Online], 57.3 (2011): 183-191. Web.  23 Jan. 2021
TY  - JOUR
AU  - Menner, Philipp 
AU  - Gerhard, Henry 
AU  - Busse, Gerd 
PY  - 2011
TI  - Lockin-Interferometry: Principle and Applications in NDE
JF  - Strojniški vestnik - Journal of Mechanical Engineering
DO  - 10.5545/sv-jme.2010.169
KW  - Lockin-ESPI; Lockin-Shearography; defect-selective imaging; interferometric depth profiling
N2  - Interferometry is relevant for non-destructive evaluation (NDE) since dimensional changes much smaller than an optical wavelength result in detectable signals. Fringe images obtained with Electronic-Speckle-Pattern-Interferometry (ESPI) or shearography display changes of surface topography between two states of an object, usually using a static load. Usually, hidden defects are found by comparing the observed fringe pattern to the one obtained on an intact reference component and to attribute observed differences to a defect. Our approach is a periodical object illumination with light that is absorbed in the surface to generate heat and a corresponding modulation of thermal expansion. At the same time fringe images are recorded (either with ESPI or shearography) to give a stack. Subsequently, each image is unwrapped and thereafter the time-dependent content of each pixel is Fourier transformed at the excitation frequency, so the result is local amplitude and phase of the modulated response at this frequency. The phase image displays local delay between excitation and response. This phase change depends on the depth where the defect is located since thermal waves are involved. In this paper, NDE-examples obtained using this new technique are presented. It is also shown how the achieved improvement as compared to conventional interferometry is up to an order of magnitude.
UR  - https://www.sv-jme.eu/sl/article/lockin-interferometry-principle-and-applications-in-nde/
@article{{sv-jme}{sv-jme.2010.169},
	author = {Menner, P., Gerhard, H., Busse, G.},
	title = {Lockin-Interferometry: Principle and Applications in NDE},
	journal = {Strojniški vestnik - Journal of Mechanical Engineering},
	volume = {57},
	number = {3},
	year = {2011},
	doi = {10.5545/sv-jme.2010.169},
	url = {https://www.sv-jme.eu/sl/article/lockin-interferometry-principle-and-applications-in-nde/}
}
TY  - JOUR
AU  - Menner, Philipp 
AU  - Gerhard, Henry 
AU  - Busse, Gerd 
PY  - 2018/06/28
TI  - Lockin-Interferometry: Principle and Applications in NDE
JF  - Strojniški vestnik - Journal of Mechanical Engineering; Vol 57, No 3 (2011): Strojniški vestnik - Journal of Mechanical Engineering
DO  - 10.5545/sv-jme.2010.169
KW  - Lockin-ESPI, Lockin-Shearography, defect-selective imaging, interferometric depth profiling
N2  - Interferometry is relevant for non-destructive evaluation (NDE) since dimensional changes much smaller than an optical wavelength result in detectable signals. Fringe images obtained with Electronic-Speckle-Pattern-Interferometry (ESPI) or shearography display changes of surface topography between two states of an object, usually using a static load. Usually, hidden defects are found by comparing the observed fringe pattern to the one obtained on an intact reference component and to attribute observed differences to a defect. Our approach is a periodical object illumination with light that is absorbed in the surface to generate heat and a corresponding modulation of thermal expansion. At the same time fringe images are recorded (either with ESPI or shearography) to give a stack. Subsequently, each image is unwrapped and thereafter the time-dependent content of each pixel is Fourier transformed at the excitation frequency, so the result is local amplitude and phase of the modulated response at this frequency. The phase image displays local delay between excitation and response. This phase change depends on the depth where the defect is located since thermal waves are involved. In this paper, NDE-examples obtained using this new technique are presented. It is also shown how the achieved improvement as compared to conventional interferometry is up to an order of magnitude.
UR  - https://www.sv-jme.eu/sl/article/lockin-interferometry-principle-and-applications-in-nde/
Menner, Philipp, Gerhard, Henry, AND Busse, Gerd.
"Lockin-Interferometry: Principle and Applications in NDE" Strojniški vestnik - Journal of Mechanical Engineering [Online], Volume 57 Number 3 (28 June 2018)

Avtorji

Inštitucije

  • Institute of Polymer Technology (IKT), Non-Destructive Testing (IKT-ZfP), Stuttgart University, Pfaffenwaldring 32, 70569 Stuttgart 1

Informacije o papirju

Strojniški vestnik - Journal of Mechanical Engineering 57(2011)3, 183-191

https://doi.org/10.5545/sv-jme.2010.169

Interferometry is relevant for non-destructive evaluation (NDE) since dimensional changes much smaller than an optical wavelength result in detectable signals. Fringe images obtained with Electronic-Speckle-Pattern-Interferometry (ESPI) or shearography display changes of surface topography between two states of an object, usually using a static load. Usually, hidden defects are found by comparing the observed fringe pattern to the one obtained on an intact reference component and to attribute observed differences to a defect. Our approach is a periodical object illumination with light that is absorbed in the surface to generate heat and a corresponding modulation of thermal expansion. At the same time fringe images are recorded (either with ESPI or shearography) to give a stack. Subsequently, each image is unwrapped and thereafter the time-dependent content of each pixel is Fourier transformed at the excitation frequency, so the result is local amplitude and phase of the modulated response at this frequency. The phase image displays local delay between excitation and response. This phase change depends on the depth where the defect is located since thermal waves are involved. In this paper, NDE-examples obtained using this new technique are presented. It is also shown how the achieved improvement as compared to conventional interferometry is up to an order of magnitude.

Lockin-ESPI; Lockin-Shearography; defect-selective imaging; interferometric depth profiling