基于彩色双通道投影的快速调制度测量轮廓术

Fast Modulation Measurement Profilometry Based on Double Color Projections

针对传统调制度轮廓术测量速度较慢的问题,本文提出了彩色双通道投影的调制度轮廓术。该方法将两个正弦光栅通过不同的通道同时成像在被测物体上,两光栅像面不重合(相互离焦),采用彩色CCD采集条纹图,利用彩色CCD的色通道性质,分离出两个单一通道的条纹图,得到其调制度分布。由于调制度比值和物体高度存在一一对应关系,由此可重建物体三维面形。文中给出了实验的设计方案、信息获取的方法、实验结果及误差分析,讨论了影响测量精度的几种原因。实验结果表明,该方法测量深孔等面形复杂物体,测量速度快,算法简单,且可以达到较高测量精度。

In order to solve the lower measurement efficiency in traditional modulation profilometry, a fast modulation profilometry is proposed based on double color projections. Two sine gratings through the different projections form color fringe on measured object surface, and pictures are gotten by color CCD. Own to arrangement in layers＇ quality of color CCD, we separate fringes into two signals, and acquire the modulation distributions. Because the modulation ratio is one-to-one correspondence to the height of object, the object is reconstructed. The design method for project of experiment, the method for acquiring modulation, the result of experiment and the deviation analysis are proposed. Several factors are discussed which affect the measurement accuracy. The result proves that this method in measuring complex objects, such as the object with deep holes, is highly efficient, simple and greatly accurate.