Constraint-guided regularization for robust phase correction in phase shifting interferometry

Phase retrieval accuracy in phase-shifting interferometry is highly sensitive to environmental vibrations and nonlinearities in the application of phase shifts, making robust phase error correction crucial for reliable optical metrology. To address this issue under noisy conditions, this work proposes a regularization-based phase correction approach that explicitly incorporates the Pythagorean identity, global quadrature orthogonality and spatial smoothness as a functional constraints. The performance of the method was evaluated through numerical simulations and validated experimentally. The results demonstrate that the proposed approach successfully mitigates phase errors, offering a robust solution for stable phase retrieval in disturbed testing environments.