Phase retrieval of arbitrary complex-valued fields through aperture-plane modulation

We propose and experimentally demonstrate a simple and robust approach for retrieving arbitrary complex-valued fields from three or more diffraction intensity recordings. We need no a priori knowledge about the object field. The convergence rate is rapid. We obtained good results using experimental data with only 80 iterations (160 fast Fourier transforms). The method does not suffer any stagnation or ambiguity problem, and it also exhibits a high immunity to noise. The technique exhibits great potential in lensless phase-contrast imaging, wave-front sensing, and metrology for a wide spectral range.