Fringe control techniques applied to holographic non-destructive testing (HNDT)

Abstract

The fringe control techniques applied to holographic non-destructive testing using real-time hologram interferometry are discussed. These techniques are of immense importance for removing high spatial frequency fringe pattern arising as a result of overall motion or gross structural deformation of the object when it is subjected to load. The removal of high spatial frequency fringe pattern is essential to view the regions of defect in the object distinctly. Experimental results are presented to support theoretical predictions.