基于线性移相误差的[WT《A》]N步移相算法

移相误差是影响移相干涉术测量精度的主要来源,针对移相器的线性移相误差,文中提出一种新型的移相干涉术算法-N步移相算法。该算法通过最小二乘法估计出移相器做等步移相时的实际移相相位,利用上述估计值代入相位计算公式获得被测物体的相位分布。同时对该算法进行仿真研究,其结果表明,算法能准确地估计移相相位,获得被测物体的精确相位分布,并可实现λ/100的高精度测量,且在测量精度上明显优于其他算法。

N-Sample Phase-Shifting Algorithm Based on Linear Phase-Shift Error

Phase-shift error is always the main source of the measurement precision in phase-shifting interferometry.In this paper,a new phase-shifting interferometry algorithm named N-sample phase-shifting algorithm is proposed,which can greatly reduce the phase reset error caused by linear phase shifting deviation.Firstly,step phase shifts of phase shifter are estimated.Secondly,the phase distribution of a fringe pattern is calculated by using the obtained phase shifts.Computer simulation shows the proposed algorithm accurately estimates the phase shift and obtains the phase distribution with an accuracy of λ/100,much better than those of existing algorithms.