传统的光栅投影法依靠相移法进行测量, 对绝对相位的计算需要应用解包裹算法完成。由于解包裹算法要求空间相位具有连续性, 因此不适合高度变化显著的物体的测量。针对该问题, 提出一种多尺度条纹投影测量的方法, 直接获取高密度条纹投影的绝对相位。通过对高密度64周期条纹扫描投影测量相位的二次拟合曲线的实验处理, 在绝对相位 [-201,201]的变化范围内, 拟合标准差达到0.096 63 rad的精度。

In terms of the calculation of absolute phase in conventional grating projection methods, the unwrapping algorithm is applied. Due to the demand upon spatial phase continuity from the unwrapping algorithm, it is not suitable for the measurement of objects with step-height. A multi-scale fringe projection measurement was put forward to tackle this problem, and the absolute phase of high-density fringe projection could be directly gained. Through the experiment upon the quadratic fitting curve of the high-density 64 periods fringe’s phase measurement, within the variation range [-201,201] of the absolute phase, the fitting standard deviation reaches the precision of 0.096 63 rad.