网格激光高反抑制与中心提取误差修正  

Grid laser high back suppression and center extraction error correction

作　　者：王标[1] 吴南南 马宇晗 姚彦峰 王永红[1] 李骏睿[1] WANG Biao;WU Nannan;MA Yuhan;YAO Yanfeng;WANG Yonghong;LI Junrui(School of Instrument Science and Optoelectronic Engineering,Hefei University of Technology,Hefei 230000,China)

机构地区：[1]合肥工业大学仪器科学与光电工程学院,安徽合肥230000

出　　处：《光学精密工程》2025年第1期57-74,共18页Optics and Precision Engineering

基　　金：安徽省人机共融系统与智能装备工程实验室项目(No.RJGR202205);合肥市自然科学基金资助项目(No.2022022);国家自然科学基金资助项目(No.52375536)。

摘　　要：线激光在扫描金属工件时,部分金属表面存在高反光区域导致扫描效果不好,网格激光相较于单线与多线而言扫描效率更快,但存在中心提取以及光平面定位困难等问题。为了满足金属工件高效实时检测的需求,设计了一种网格激光的偏振态获取方法,对偏振片旋转角度进行标定,达到对高反光表面的最佳程度抑制。基于法向量的激光中心与光平面对应方法,利用像素Hessian矩阵特征值最大时的特征向量,将激光中心与所属的光平面对应。采用基于仿射变换的中心提取方法,将非正交网格通过仿射变换转为正交后提取中心点,提高三维重建的准确性。最后建立了测量误差与高度的误差修正模型,减少了测量系统误差。实验结果表明,网格激光传统算法扫描金属表面高反光区域,扫描结果会有边缘缺失,测量误差为0.8 mm;而本文所提方法能够有效抑制金属表面高反光带来的影响,实现激光中心提取与光平面的准确对应,测量误差达到0.39 mm,最后经过误差修正,金属表面高光区域测量精度有较大提升,测量误差可达0.1 mm。本文所提方法与网格激光传统算法测量结果相比,测量误差减少了87.5%。该方法实现了金属表面高反光抑制下的网格激光扫描三维重建,扫描效率与测量精度得到提升,为未来的工业测量提供方法和参考。When a line laser scans metal workpieces,the high reflectivity of certain metal surfaces often leads to poor scanning results.While grid laser scanning is faster than single-line and multi-line scanning,challenges such as center extraction and optical plane positioning hinder its ability to meet the demands of efficient real-time detection of metal workpieces.This study proposes a novel method to address these is-sues by calibrating the rotation angle of a polarizer to optimize the suppression of high surface reflectivity through the polarization state of the grid laser.In addition,a laser center mapping technique based on nor-mal vectors is developed,where the laser center is mapped to the optical plane using the eigenvector corre-sponding to the maximum eigenvalue of the pixel Hessian matrix.A center extraction method based on af-fine transformation is also introduced,enabling the transformation of non-orthogonal grids into orthogonal ones to improve the accuracy of 3D reconstruction.Furthermore,an error correction model is established to reduce measurement system errors by accounting for variations in height.Experimental results demon-strate that the traditional grid laser algorithm struggles with missing edges when scanning highly reflective metal surfaces,resulting in a measurement error of 0.8 mm.In contrast,the proposed method effectively suppresses the impact of high reflectivity,achieves accurate mapping between the laser center and the opti-cal plane,and reduces the measurement error to 0.39 mm.After error correction,the accuracy is further improved,achieving a measurement error of just 0.1 mm,representing an 87.5%reduction compared to the traditional grid laser algorithm.In conclusion,this study investigates 3D reconstruction using grid laser scanning under high-reflection suppression for metal surfaces,significantly improving both scanning effi-ciency and measurement accuracy.The proposed method provides a valuable approach and reference for future industrial measurement applications.

关 键 词：三维测量 网格激光 偏振态 中心提取 法向量 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术] TN249[自动化与计算机技术—计算机科学与技术]