  This paper reported a general noninterferometric high-accuracy quantitative
phase imaging (QPI) method for arbitrary complex valued objects. Given by a
typical 4f optical configuration as the imaging system, three frames of
small-window phase modulation are applied on the object Fourier spectrum so
that redistributed intensity patterns are produced on the image plane, in which
the object phase emerges at different degree. Then, an algebraic relationship
that connects the object phase with the output intensity is established to
provide us with an approximate closed form phase recovery. Further, an
efficient iterative optimization strategy is developed to turn that approximate
solution into an accurate one. Due to the linear convergence property of the
iteration, a high accuracy phase recovery is achieved without requiring heavy
iterations. The feasibility and accuracy of the proposed method are verified by
both numerical simulations and experiments on diverse phase objects.
