提出了一种基于显微图像拼接技术的视觉坐标测量方法, 也就是利用图像自身的空间坐标信息实现坐标测量的方法。针对测量显微镜获取微小零件图像所具有较精细的纹理特征, 提出了一种基于点映射互相关配准算法, 对局部重叠的序列图像进行拼接。借助于玻璃标准尺对系统进行了严格的标定, 重点对不同放大倍数下的拼接误差进行了计算与分析。并通过微小零件尺寸测量的实例说明了该算法的有效性。多种实验研究表明, 该测量方法的相对误差可优于 1%, 分辨力可小于 1 μm。

A vision coordinate measurement method based on microscopic image mosaic technique is proposed, that is to say, the coordinate measurement is implemented with spacial coordinate information in image itself. According to fine texture feature on small parts images captured by the measuring microscope, a cross-correlation matching algorithm based on the point map was presented to mosaic sequence images provided with partial overlap. By means of a rigorous system calibration using glass standard rule, mosaicing errors were calculated and analyzed on different microscopic magnification. Then the measuring example of small part dimensions was illuminated, which shows that the algorithm is effective. Several experiment studies show that relative error is superior to 1% and resolution is less than 1 micrometer.