A phase imaging system based on complex field sensor is analyzed, and experiments are performed to verify three methods of phase retrieval, namely, multi-wavelength digital holography, multi-aperture Zernike wavefront sensing and coherent diffractive imaging. The diffracted wavefront scattered from an object (a randomly rough surface or a surface with a known feature) is captured with a CCD in the far-field and the wavefront phase at the object surface is reconstructed using an optimized iterative algorithm. Based on the method chosen, one or two diffraction patterns were captured. The results demonstrate the potential of the proposed complex field imaging sensor for in-situ quality control of additively manufactured objects.
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