Phase retrieval from modulated intensity patterns

The interferometric measurements are among the most popular methods of non- contact, non-intrusive surface and volume characterization. Figure 1 shows an interferogram [1 of 3 minimally in the phase shifting interferometry1,2 (PSI)], that has several features that are considered challenging in the phase reconstruction: it has many fringes, some closed and some open; it high intensity gradients with a non-uniform contrast; and it is defined within a circular boundary on a rectangular array. We report a novel method for the phase determination, applicable to the majority of the existing phase reconstruction techniques.