Toward higher-frequency fringe projection profilometry with fewer patterns

Phase unwrapping is crucial in fringe projection profilometry (FPP) 3D measurement. However, achieving efficient and robust phase unwrapping remains a challenge, particularly when dealing with high-frequency fringes to achieve high accuracy. Existing methods rely on heavy fringe projections, inevitably sacrificing measurement efficiency. To address this problem, we propose a novel, to the best of our knowledge, phase analysis method based on composite fringe patterns. By embedding a multi-period space-varying phase shift (SPS) into the phase domain, the noise amplification issues in high-frequency phase unwrapping is effectively addressed. Our proposed method requires fewer patterns than conventional methods, utilizing only four fringe patterns for absolute phase retrieval. Experimental results confirm the feasibility of our proposed method and demonstrate its superior efficiency and accuracy through quantitative comparisons.