基于标定参数修正的远心成像精密三维测量  

Precision three-dimensional measurement method of telecentric imaging based on calibration parameter correction

作　　者：李文杰 刘伍浪[1] 王贝贝 黄玉源 刘规杰 李富权 LI Wenjie;LIU Wulang;WANG Beibei;HUANG Yuyuan;LIU Guijie;LI Fuquan(Key Laboratory of Guangxi Manufacturing System and Advanced Manufacturing Technology(School of Mechanical and Electrical Engineering,Guilin University of Electronic Science and Technology),Guilin 541004,China;Digital Laser Imaging and Display Engineering Research Center of Ministry of Education,Suzhou 215006,China;Guilin Changhai Development Limited Company,Guilin 541001,China)

机构地区：[1]广西制造系统与先进制造技术重点实验室(桂林电子科技大学机电工程学院),广西桂林541004 [2]数码激光成像与显示教育部工程研究中心,江苏苏州215006 [3]桂林长海发展有限责任公司,广西桂林541001

出　　处：《光学精密工程》2025年第2期165-175,共11页Optics and Precision Engineering

基　　金：广西制造系统与先进制造技术重点实验室(主任基金)项目(No.23354S006);数码激光成像与显示教育部工程研究中心资助项目(No.SDGC2319);国家自然科学基金(No.52005119)。

摘　　要：远心成像具有稳定放大倍率、大景深、低畸变等优点,在三维精密测量领域备受关注。然而,由于制造工艺的限制,远心镜头的孔径光阑无法完美地置于焦平面上,导致偏离光轴微小角度的光线也能进入,从而引入测量误差。针对该误差,提出了一种基于标定参数修正的远心三维重构模型。在理论上分析了远心光路非理想性产生的原因,并构建了与成像深度相关的系统标定参数模型,补偿因光路非理想性引起的测量误差。以对焦平面的标定参数为基础,基于控制变量法和最小二乘拟合算法建立径向畸变系数与成像深度之间的数学多项式表达式。采用随机采样一致性算法滤除相位噪声,并基于多项式模型建立相位-深度映射关系。三维重构时,根据绝对相位确定的深度信息修正径向畸变系数,继而实现高精度的横向尺寸重构。在标定板和标准球实验中,系统参数修正前后被测线段的测量误差由28.8μm降为4.8μm,标准球的直径测量误差由35.2μm降为8.1μm,验证了所提出方案的可行性与必要性。该方法为远心光路系统的精密测量提供了一种有效的参数修正思路,丰富了远心三维测量技术。Telecentric imaging has the advantages of stable magnification,large depth of field and low distortion,which has attracted much attention in the field of three-dimensional precision measurement.However,due to manufacturing limitations,the aperture stop of a telecentric lens cannot be perfectly positioned at the focal plane,allowing light rays with slight angular deviations from the optical axis to enter,thereby introducing measurement errors.To address this issue,a telecentric 3D reconstruction model based on calibration parameter correction was proposed.The theoretical analysis of the causes of telecentric optical path non-ideality led to the construction of a system calibration parameter model related to the imaging depth,which compensated for the measurement error caused by optical path non-ideality.Based on the calibration parameters of the focal plane,the mathematical polynomial expression between the radial distortion coefficient and the imaging depth was established based on the control variable method and the least squares fitting algorithm.A random sampling consistency algorithm was employed to filter out the phase noise,and the phase-depth mapping relationship was established based on the polynomial model.During the process of three-dimensional reconstruction,the radial aberration coefficients were corrected based on the depth information determined from the absolute phase,thereby achieving high precision in the reconstruction of the lateral size.In the calibration plate and standard ball experiments,the measurement error of the measured line segment was reduced from 28.8μm to 4.8μm,and the measurement error of the diameter of the standard ball was reduced from 35.2μm to 8.1μm,thereby verifying the feasibility and necessity of the proposed scheme.This method provides an effective parameter correction idea for the precise measurement of the telecentric optical path system,and enriches the telecentric three-dimensional measurement technology.

关 键 词：远心成像 三维成像 精密测量 条纹投影轮廓术 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]