The use of carrier fringes and FFT in holographic nondestructive testing

The carrier fringe technique for holographic interferometry was discussed. The use of fast Fourier transforms (FFT) in the method enabled phase measurement from fringe patterns caused due to interference of tilted wavefronts. The FFT approach was used to extract deformation information automatically from complex interferograms and was shown to have considerable potential for solving images in its ability to extract data in the presence of pixel noise.