Phase reconstruction from undersampled intensity patterns

We demonstrate the uniqueness and convergence of phase recovery from high-s patial-frequency and undersampled intensity data. Furthermore, this is acco mplished without the ambiguities that arise in phase unwrapping and without the need to employ a priori information. The method incorporates the techn ique of line integration of the phase gradient to find the first approximat ion to the phase and the algorithm of synthetic interferograms to find the unknown phase with high accuracy. The method may be used with any experimen tal method that at a certain data processing step obtains generalized sine and cosine intensity functions. (C) 2000 Optical Society of America [S0740- 3232(00)00601-3].