PHASE-SHIFTING HOLOGRAPHIC MOIRE - PHASE-SHIFTER ERROR-INSENSITIVE ALGORITHMS FOR THE EXTRACTION OF THE DIFFERENCE AND SUM OF PHASES IN HOLOGRAPHIC MOIRE

Phase-stepping techniques for the measurement of the difference and su m of phases in holographic-moire-based interferometers are described. The phase-recovering algorithms for the extraction of this phase infor mation is relatively insensitive to the inaccuracies of the phase-shif ting device. This development promises not only to extend the domain o f measurements but also to improve significantly the accuracy that can be achieved in deformation analysis and nondestructive testing of dif fuse objects.