基于复矢量插值的激光波数扫描干涉相位快速提取算法

Fast Wavenumber Scanning Interferometry Phase Extraction Algorithm Based on Complex Vector Interpolation

激光波数扫描干涉技术通过透视测量复合材料内部的应变场,实现复合材料高精度无损透视检测,测量精度达到微应变级别,这是目前微米级缺陷无损检测的重要手段之一。激光波数扫描干涉技术按照波数k轴方向提取出干涉信号光强序列,然后对每个像素位置的干涉光强序列进行数据处理。通过离散的傅里叶变换得到像素点对应的频谱图,运用基于误差补偿的相位提取算法提取到像素点的相位,遍历所有的像素点得到相位卷绕图,最后使用相位解卷绕技术,得到物体的表面信息。在相位提取的步骤中进行改进,提出基于复矢量插值的激光波数扫描干涉相位快速提取算法,通过间隔采样减少计算所需要花费的时间,复矢量插值保证结果的准确性,减少运算所需要花费的时间,在此基础上同时也可以保证得到的解卷绕相位对实际的影响不大。

Laser wavenumber scanning interferometry technology extracts the interference signal intensity sequence according to the wavenumber k-axis direction,and then processes the interference light intensity sequence at each pixel position.The spectrogram corresponding to the pixel is obtained by discrete Fourier transform,the phase extraction algorithm based on error compensation is used to extract the phase of the pixel,the phase winding map is obtained by traversing all the pixels,and finally the phase dewinding technology is used to obtain the surface information of the object.This paper improves the steps of phase extraction,and proposes a laser wavenumber sweeping interference phase fast extraction algorithm based on complex vector interpolation,which reduces the time required for calculation through interval sampling,and ensures the accuracy of the results and reduces the time required for operation.On this basis,it can also ensure that the obtained dewinding phase has little effect on the actual situation.