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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 49, Iss. 5 — Feb. 10, 2010
  • pp: 897–903

Real-time slope mapping and defect detection in bent plates using Talbot interferometry

Satya Prakash Trivedi, Shashi Prakash, Santosh Rana, and Osami Sasaki  »View Author Affiliations

Applied Optics, Vol. 49, Issue 5, pp. 897-903 (2010)

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We demonstrate a simple method for obtaining slope contours of bent plates using Talbot interferometry. The technique has been used to map slope contours of polymethyl methacrylate specimens of different shapes. The Talbot image of a coarse grating is projected onto a specimen such that the self-image is backreflected onto the same grating again. As a Talbot interferometer is basically a grating shearing inter ferometer, it results in the generation of characteristic slope maps of the specimen under test. Results of the investigation match well with other slope-mapping techniques. Validation of experimental results with theoretical predictions in the case of a cantilever beam specimen has been undertaken. Accuracy of about 4.7% with respect to theoretical predictions is obtained.

© 2010 Optical Society of America

OCIS Codes
(050.2770) Diffraction and gratings : Gratings
(070.6760) Fourier optics and signal processing : Talbot and self-imaging effects
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology

ToC Category:

Original Manuscript: August 25, 2009
Revised Manuscript: December 14, 2009
Manuscript Accepted: December 28, 2009
Published: February 5, 2010

Satya Prakash Trivedi, Shashi Prakash, Santosh Rana, and Osami Sasaki, "Real-time slope mapping and defect detection in bent plates using Talbot interferometry," Appl. Opt. 49, 897-903 (2010)

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