Zero-order suppression in slightly off-axis holography based on Fourier ptychographic reconstruction

Since the spectral aliasing degree of object information and background intensity affects the phase demodulation accuracy directly through the linear Fourier domain filtering, conventional holography suffers from the problem of incompatibility between high reconstruction quality and high throughput imaging. The enhancement of space-bandwidth product by slightly off-axis holography is necessarily accompanied by zero-order suppression; otherwise, artifacts will be formed on the phase image due to the residual background intensity information. We innovatively propose a zero-order suppression method for slightly off-axis digital holography based on Fourier ptychography (FP), terms as FPDH. Inspired by the FPM phase retrieval process, the hologram spectrum recovery is viewed as a nonlinear optimization problem, and the object wavefront is recovered by a method like GS algorithm. Experimental results show that FPDH can provide higher reconstruction accuracy and better image quality compared with other methods.