任意相位差条纹信号细分方法的研究

Research on Subdividing Method for Random Phase Difference Fringe Signals

为消除传统细分方法中由于两路条纹信号不正交引入的细分误差,提出了一种可对任意相位差条纹信号直接细分的新方法。根据两路条纹信号的极性和幅值大小,把一个信号周期分成8 个区段。高速采集两路条纹信号,通过判断信号采样点所处的区段是否跳变对信号幅值交点进行动态跟踪。对不足一个周期的条纹移动,当测量出起点与终点的幅值,计算出其所在的区段及位置后,结合两路信号的交点,可实现对任意相位差条纹信号的细分。实验结果表明,该方法突破了传统细分方法必须信号正交的限制,可对任意相位差信号进行准确地细分,降低了条纹测量中器件安装与调试的难度。

In order to eliminate the subdividing error caused by fringe signals which are not in phase quadrature, a new method that can directly subdivide fringe signals for random phase relationship is presented. One signal period can be divided into eight sections according to the fringe signal polarity and amplitude. The fringe signals are sampled at high speed so that the section in which the sampled point locates can be calculated in real time. The fringe signal absolute amplitude joints can be dynamically traced by judging whether two successive sampling points are in different sections. After the amplitudes of fringe signals star point and stop point are sampled, the section in which they locate can be calculated, the fraction fringe can be worked out by combination of joints of start point and stop point. Experimental results show that the new method can subdivide fringe signals correctly even when they are in random phase relationship. The new method breaks through the limitation that the signals must be in phase quadrature for conventional subdividing methods and has better anti-jamming ability.