Phase unwrapping algorithm based on phase diversity wavefront reconstruction and virtual Hartmann-Shack technology

• Ying Zhang, Hua Bao, Naiting Gu, Shuqi Li, Yiqun Zhang, and Changhui Rao
• received 12/13/2023; accepted 04/24/2024; posted 04/24/2024; Doc. ID 515821
• Abstract: Phase unwrapping algorithms play a crucial role in various phase measurement techniques. Traditional algorithms cannot work well in strong noise environments, which makes it very difficult to obtain the accurate absolute phase from the noisy wrapped phase. In this paper, we proposed a novel phase unwrapping algorithm based on phase diversity (PD) wavefront reconstruction and virtual Hartmann-Shack (VHS) technology, called PD-VHS, which coped well with the large-scale noise in the wrapped phase. In simulation experiments, hundreds of random noise wrapped phases, containing the first 45 Zernike polynomials and the wavefront RMS= 0.5λ, 1λ,are used to compare the classical quality-map guided algorithm, the VHS algorithm with decent noise immunity and our PD-VHS algorithm. When SNR drops to just 2dB, the mean RMSEs of residual wavefront between the unwrapped result and the absolute phase of quality-map guided algorithm and VHS algorithm are up to 3.99λ, 0.44λ and 4.29λ, 0.85λ respectively, but our algorithm's are low to 0.11λ and 0.17λ. Simulation results demonstrated that the PD-VHS algorithm significantly outperforms the quality-map guided algorithm and the VHS algorithm under strong noise conditions.