提出了一种基于彩色摄像机的双波长激光剪切散斑干涉测量方法,用于同步测量变形物体的面内和面外位移导数。两束不同波长的激光以相同的入射角,同时对称地照射在被测物体表面。基于改进的迈克耳孙干涉光路并仅用一个相移器,建立了时间相移的双波长激光剪切散斑干涉测量系统。通过一个3芯片彩色相机的绿色和蓝色通道记录两个不同波长激光干涉形成的干涉图。运用Carré算法从分离的绿色和蓝色剪切散斑干涉条纹图中提取出与面内和面外变形导数分量相关的相位。悬臂铝梁的变形测量结果验证了该测试系统的可行性。

A color-camera-based shearography system using dual-wavelength lasers was developed for simultaneously measuring the in-plane and out-of-plane displacement derivatives of a deformed object. Lasers of dual wavelengths are arranged to symmetrically and simultaneously illuminate on the object with identical angles of incidence. A set of phase-shifter and a modified Michelson interferometer are used to build a temporal-phase-shift dual-wavelength shearography. The interferograms formed by the two wavelength are recorded by one 3-chip color camera with green and blue channels. The phases related to the in-plane and out-of-plane components are extracted from the shearograms by using Carré algorithm. Experiment on a cantilevered aluminum beam deformation was performed to verify the feasibility and the capability of the testing system.