面内微位移测量的散斑相位涡旋相关方法研究

提出了用散斑相位涡旋相关方法测量面内微位移。 首先利用拉盖尔-高斯变换, 将光强灰度图的实值信号I(x,y)变为复光强信号(x,y),获得涡 旋分布矩阵；然后,以涡旋 核结构参数的偏心率e作为特征因子进行相关运算；最终实现面内微位移的测量。在相同计 算机配置下,对毛玻璃的面内位移进行了测量,结果显示,散斑相位涡旋相关法的平均计算 时间为35.4ms,传统数字散斑相关法(DSCM)的平均计 算时间为376.7ms,而两者的相对误差均小于5%,这与数值模拟结果 相符。实验结果与数值 模拟结果表明,散斑相位涡旋相关方法可准确测量面内微位移,与传统DSCM相比,在保持相 同测量精度的前提下,计算效率至少提高了1个数量级。

Micro in-plane displacement measurement using digital speckle correlation method based on phase vortices

Micro in-plane displacement measureme nt using digital speckle correlation method (DSCM) based on phase vortices is proposed in this paper.First we get a matrix o f vortices distribution through Laguerre-Gauss transform,which turns real-valued signals I (x,y) of the intensity gray image into complex intensity signals (x,y).T hen we take eccentricity of the core structure parameter as characteristic factor to make correlation operation.Finally,the mic ro in-plane displacement can be measured.Under the same computer configuration,the in-plane displacement of the roughness glass was measured.The average calculating time o f this proposed method was 35.4ms,however,the average calculating time of the t raditional DSCM was up to 376.7ms.Experimental results are well agreed with the numerical simulation results.Results show that the speckle phase vortices correlation method can exactly measure micro in-plane displacement.Compared wi th the traditional DSCM,the calculation time increases at least one order of magnitude in keeping equivalent measuring accuracy.