A 3D Reconstruction Method Based on Dual-Frequency Stripes and Lookup Tables*

Phase jumps, discontinuities, and slow unfolding speed are common drawbacks of traditional spatial phase unfolding methods. To overcome these problems, this paper proposes an absolute phase unfolding method based on dual-frequency stripe and lookup tables. First, the dual-frequency stripe method is presented, which integrates the high-frequency stripe and the unit-frequency stripe into one stripe pattern, necessitating just over five stripe patterns to obtain high-quality phase data. Secondly, a fast phase unfolding algorithm with lookup tables is used to precalculate modulation intensity and phase principal values and store the respective results. This algorithm circumvents the extremely time-consuming actangent function, reduces the number of quadratic operations, and achieves fast data processing. The experimental results show that the proposed method is 31.60 times faster than the traditional three-frequency four-step phase-shifting method, while also having the number of stripes required for processing. Our findings hold significant implications for the pursuit of rapid 3D reconstruction.