为实现微球形貌检测中子孔径数据的快速、准确拼接,给出基于点衍射干涉原理的微球形貌检测模型,分析了干涉场横向分辨率的分布规律,提出基于映射图像匹配的子孔径拼接方法。通过形貌数据的等尺度变换,实现横向分辨率均匀化,并将三维点云数据进行降维处理,映射生成二维图像,从而将形貌数据的旋转关系转化为图像坐标的平移关系,再通过图像匹配算法对特征点进行匹配,得出子孔径坐标系间的对应关系,从而实现拼接。最后通过仿真实验验证了该方法的可行性和有效性。

In order to stitch the sub-aperture data rapidly and precisely in microsphere profile inspection, the model of microsphere surface measurement was given, which was based on point diffraction interference. After analyzing the distribution of interference field lateral resolution in detail, a method of sub-aperture stitching based on mapping image matching was proposed. After equal-scale transformation of profile data, the homogenization of lateral resolution was achieved. The dimension of 3D point clouds data was reduced to a mapped 2D image for transforming the sub-aperture rotation-ship of the profile data to a translation relation on the CCD coordinate system. And the corresponding transformation offset between sub-apertures could be obtained by the feature points matching in ways of image matching algorithm, so the sub-aperture stitching could be realized. Finally, the feasibility and effectiveness of the proposed mapping image matching method for sub-aperture stitching was proved by the simulation experiment.