Novel concepts in phase shifting interferometry and their applications to holographic moiré

To date, no phase shifting technique has been implemented that accommodates the requirements inherent in holographic moiré . In the present form of measurement, only the value of one component of difference in displacement carried on moiré is quantified, whereas information carried on the carrier is lost. However, in several interferometers, incorporation of this information would add value to the systems as in many applications the capacity for registering simultaneously information carried on moiré and on carrier is essential. A technique capable of achieving this objective represents a substantial advancement in phase shifting as it would circumvent limitations exhibited by the present crop of phase shifting techniques of measuring only one displacement component at any given instant of time. The aim of this work is to design novel phase shifting algorithms which would add the capability to measure simultaneously values of displacement components carried on the moiré and on the carrier. The proposed research thus envisages developing new concepts in phase shifting and imparting stimulus to the measurement techniques in comparative holographic moiré which in spite of having immense potential have largely remained unexploited because of the unavailability of powerful data-analysis techniques. The introduction of high-resolution methods for the first time in phase shifting interferometry and their ability to successfully estimate multiple phase information in holographic moiré are among the salient features of this research.