利用结构光辅助立体视觉技术在三维测量领域可以很好地解决被测物特征稀疏的问题，从而实现对物体几何尺寸的高精度测量。提出了利用极线和条纹级次双约束的方式，通过双目相机中的极线约束原理和多频外差法得到的光栅条纹级次进行混合约束，降低了立体匹配的待匹配区域。立体匹配过程中设计了一种带权值的窗口模板，利用相位信息配合模板匹配的方式确定初始匹配点，并通过初始匹配点与附近点的相位差值利用二次曲线拟合方法实现亚像素级匹配。实验表明:该方法在较小视场测量中应用良好，对直径10 mm大小的球体可以实现快速、准确的测量。

Structured light-assisted stereo vision technology can solve the problem of the measured object with sparse characteristics, so as to realize the high precision measurement of the geometric dimension of the object.The method of using the polar line and the fringe order double constraint was proposed, which was based on the principle of polar constraint in binocular camera and fringe order in multi-frequency heterodyne. Using this method, the stereo matching area was reduced. And during the stereo matching process, a weighted image template was used, the initial matching point was determined by using the phase information and the similarity template matching method, and the sub-pixel matching was realized by the two-dimensional curve fitting method according to the spatial distance and the phase difference of the initial matching point and the polar line. Experiments show that the method is applied well in small field of view measurement, and can achieve fast and accurate measurement for spheres with a diameter of 10 mm.