相移阴影叠栅轮廓术具有分辨力高和可自动测量的特点, 但该技术需要预先对测量灵敏度进行标定, 实现过程复杂。为了简化其标定过程, 提出一种基于3帧条纹图的实时测量灵敏度标定技术。所提方法利用垂直光栅面精确移动光栅, 获得3帧相移条纹图; 再通过不同帧条纹图相减去除条纹图背景, 发展了一种基于矩阵范数的相移算法, 提取了引入的相移; 利用相移与测量灵敏度间的关系实现了测量灵敏度的快速标定。实验结果表明, 所提方法操作简单, 应用灵活, 并且为测量灵敏度的标定提供了一种闭合解, 其标定精度优于传统的Dirckx方法。

Phase shift shadow moiré profilometry technique has the characteristics of the high definition and automatic measurement, but it requires the calibration for the measurement sensitivity in advance, and the implementation process is complicated. In order to simplify the calibration process, a calibration technique to measure sensitivity in real time based on three frame fringe patterns is proposed. A grating is shifted with vertical grating plane precisely and three frame phase shift fringe patterns are obtained. The fringe pattern background is removed by the subtraction between different frame fringe patterns. A phase shift algorithm based on the matrix norm is developed to extract the introduced phase shift. Rapid calibration of measurement sensitivity is obtained based on the relationship between phase shift and measurement sensitivity. Experiment results show that the proposed method is simple, flexible and can provide a closed-form solution for the calibration of measurement sensitivity. The calibration precision of the proposed method is better than that of the traditional Dirckx method.