Enhanced characterization of sub-surface defects using fringe-shifted shearograms

Authors

Francesca Celine Catalan ⋅ PH National Institute of Physics, University of the Philippines Diliman
Anne Margarette Maallo ⋅ PH National Institute of Physics, University of the Philippines Diliman
Percival Almoro ⋅ PH National Institute of Physics, University of the Philippines Diliman

Abstract

A technique for fringe analysis based on numerically phase-shifted shearograms is demonstrated experimentally. The contrast of the standard deviation of the shearograms facilitates detection of usually obscured spatial features in fringe patterns such as the location of object loading point and sub- surface defects. Nominal strain resulting to less than one shearogram fringe is also detected demonstrating the sensitivity of the algorithm to low-loading conditions. Compared to beam propagation-based algorithms to generate the phase maps, the advantage of numerical phase-shifting is the reduced computational load. The technique can be implemented in the analyses of both phase difference maps and interferograms, thus, can be extended to live interferogram analysis of dynamic systems.

Downloads

Issue

2011: Proceedings of the 29th Samahang Pisika ng Pilipinas National Physics Congress

Article ID

SPP2011-1B-2

Section

Acoustics, Optics, Photonics

Published

2011-10-24

How to Cite

[1]

FC Catalan, AM Maallo, and P Almoro, Enhanced characterization of sub-surface defects using fringe-shifted shearograms, Proceedings of the Samahang Pisika ng Pilipinas 29, SPP2011-1B-2 (2011). URL: https://proceedings.spp-online.org/article/view/SPP2011-1B-2.