Change search
ReferencesLink to record
Permanent link

Direct link
Vibration measurements by pulsed digital holographic endoscopy
Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.ORCID iD: 0000-0002-9031-4331
2005 (English)In: Eighth international symposium on laser metrology: macro-, micro-, and nano-technologies applied in science, engineering, and industry, Bellingham: SPIE - International Society for Optical Engineering, 2005, 729-734 p.Conference paper (Refereed)Text
Abstract [en]

Digital holographic interferometry in combination with a flexible fiber endoscope allows high precision measurements of deformations on hidden objects surfaces, inside cavities and objects with small access apertures. A digital holographic endoscopy system is described with a frequency-doubled, twin oscillator Q-switched pulsed Nd:YAG laser as light source. A sequence of digital hologram pairs are recorded with a maximum repetition rate of 260 ms. Each digital hologram is captured at separate video frames of a CCD-camera. The time separation between the laser pulses from each cavity can be set in the range from 50 to 500 mu s. The digital holograms are transferred to a PC via a frame grabber and evaluated quantitatively by the Fourier transform method. The resulting phase fringe pattern has the information needed to evaluate quantitatively the amount of the deformation. Experimental results of vibration measurements of hidden mechanical and biological object surfaces are presented. The quality of the results obtained by mechanical object surfaces is usually higher than for biological surfaces. This can be explained easily by the fact that a biological surface is much more complex than a mechanical surface in the sense that some parts of the surface may reflect the light well whereas other parts may absorb the light. Also, biological surfaces are translucent, which means that part of the light may enter inside the sample where it may be absorbed or reflected.

Place, publisher, year, edition, pages
Bellingham: SPIE - International Society for Optical Engineering, 2005. 729-734 p.
, Proceedings of the society of photo-optical instrumentation engineers (SPIE), ISSN 0277-786X ; 5776
Keyword [en]
pulsed digital holography, fibre optic endoscope, dynamic measurements, vibrations analysis, non-destructive testing
National Category
Atom and Molecular Physics and Optics
URN: urn:nbn:se:umu:diva-120447DOI: 10.1117/12.611745ISI: 000228899900090ISBN: 0-8194-5757-4OAI: diva2:929651
8th International Symposium on Laser Metrology, FEB 14-18, 2005, Merida, MEXICO
Available from: 2016-05-19 Created: 2016-05-16 Last updated: 2016-05-27Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Schedin, Staffan
By organisation
Department of Applied Physics and Electronics
Atom and Molecular Physics and Optics

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

ReferencesLink to record
Permanent link

Direct link