基于光栅投影三维测量的相位展开方法研究

Phase Unwrapping Method Based on Grating Projection 3D Measurement

为了提升光栅条纹解相位的精度与效率,从时间序列的角度,对多频外差与相移法进行优化。按照展开频率的重要性选择不同步数的相移进行相位主值的求解,主频率选用四步相移,其他频率选用三步相移,最后利用外差原理进行光栅条纹的相位展开。通过试验结果证明算法的可行性,且此优化算法相比于传统的格雷码展开法精确度更高,投影图像更少,对比于常规的多频外差法,在没有降低精度的前提下投影图像更少,提高测量效率。

In order to improve the accuracy and efficiency of the phase solution of the grating fringe,this paper optimizes the multi-frequency heterodyne and phase shift method from the perspective of time series. According to the importance of the unfolding frequency,the phase shift of the asynchronous number is selected to solve the main value of the phase. The four-step phase shift is used for the main frequency,and the three-step phase shift is used for other frequencies.Finally,the heterodyne principle is used to expand the phase of the grating fringe. The experimental results prove the feasibility of the algorithm. Compared with the traditional Gray code expansion method,this optimization algorithm has higher accuracy and fewer projected images. Compared with the conventional multi-frequency heterodyne method,it can project fewer images without reducing the accuracy and improve the measurement efficiency.