Gerchberg迭代法在三维面形测量中的应用

在基于结构光照明的三维面形测量中,针对有孤立区域物体的条纹图像存在不规则缺陷的问题,提出先对其进行Gerchberg迭代,消除或减少条纹缺陷,获取较完善的迭代条纹,然后再利用傅里叶变换轮廓术(FTP)重建面形。设计了迭代流程,并分析了影响迭代精度的因素,解决了光学加工用具磨盘表面不完善条纹Gerchberg迭代过程中存在的问题,成功地重建了磨盘的三维面形。该工作为表面存在孤立区域的被测物体三维面形测量提供了可供参考的技术方案,也给可实时形变的应力盘三维面形动态测量奠定了基础。

Application of Gerchberg iterative algorithm in three-dimensional shape measurement

Among 3D profilometry methods with structured illumination,Gerchberg iterative algorithm is applied to process the irregular defect fringes acquired from the isolated object surface,and reconstruct its 3D shape.The main idea is that the missed fringe signal in the grooves will be created by Gerchberg iteration,and then the 3D shape is successfully reconstructed from the integrated fringe combining the original fringe with the renascent one based on Fourier transform profilometry(FTP).The whole iterative process is designed,and the factors that affect the accuracy are analyzed.The problem is solved by Gerchberg iteration to a grinding disc with many grooves of the optical process,and it is successful to the reconstruction of the 3D shape.The method provides a technical reference solution of the isolated region of the 3D shape measurement,and provides a scientific basis on the dynamic 3D shape measurement of the stress lab.