采用LD的光源步进条纹投影三维测量系统  

Fringe projection based three-dimensional measurement system by the light-source-stepping method using LD

作　　者：应晓霖 姚建云 张晓松 楚冬娅 李勇[1] Ying Xiaolin;Yao Jianyun;Zhang Xiaosong;Chu Dongya;Li Yong(Institute of Information Optics,Zhejiang Normal University,Jinhua,Zhejiang 321004,China;Key Laboratory of Optical Information Detecting and Display Technology of Zhejiang Province,Jinhua,Zhejiang 321004,China Abstract)

机构地区：[1]浙江师范大学信息光学研究所,浙江金华321004 [2]浙江省光信息检测与显示技术重点实验室,浙江金华321004

出　　处：《光电工程》2021年第11期41-49,共9页Opto-Electronic Engineering

基　　金：浙江省自然科学基金资助项目(LY17F050002)。

摘　　要：在采用LED的光源步进法三维测量系统中,由于LED发散角大,在短距离内就达到较大的条纹投影面积,造成系统工作距离短。另外大功率LED发光面尺寸大导致条纹对比度低,投影高亮度、高对比度的条纹困难。为解决上述问题,提出在光源步进法投影装置中采用激光二极管(LD)作为光源,实现高亮度、高对比度相移条纹投影。采用该投影装置与双目摄像机设计了便携、高速的三维测量系统。首先利用改进的傅里叶变换轮廓术获取变形条纹相位及调制强度;接着利用激光散斑的随机性,在调制强度图中实现双目图像的粗匹配;然后在粗匹配的基础上进行条纹相位展开,利用相位实现精匹配;最后获得待测物体三维形貌。利用设计的系统进行了实验验证。系统的测量体积为360 mm×290 mm×100 mm,采集的三维数据最多为1280×1024点。实现了100 f/s的三维形貌测量速度,对平面的测量标准偏差为0.19 mm,对5个间隔距离为1.00 mm的平面进行了测量,测量距离的平均误差为0.05 mm。In the three-dimensional(3D)measurement system by the light-source-stepping method using LED,due to the large divergence angle of LED,the large fringe projection area can be achieved in a short distance,resulting in a short working distance of the system.In addition,the large luminous size of high-power LED leads to low fringe contrast,and it is difficult to project fringes with high brightness and high contrast.To solve the above problems,it is proposed to use laser diode(LD)as the light source to realize high brightness and high contrast phase-shift fringe projection in the light-source-stepping projection device.A portable and high-speed three-dimensional measurement system is designed by using the projection device and binocular camera.Firstly,an improved Fourier transform profilometry is used to obtain the phase and modulation of deformed fringe.Secondly,using the randomness of laser speckle,the rough matching of the binocular image is realized in the modulation map.Then,the fringe phase is unwrapped on the basis of rough matching,and the phase is used to realize fine matching.Finally,the three-dimensional shape of the object to be measured is obtained.The experimental verification is carried out by using the designed system.The measurement volume of the system is 360 mm×290 mm×100 mm,and the maxi-mum 3D point captured is 1280×1024 points.The 3D shape measurement speed of 100 f/s was achieved.The measurement standard deviation of the plane is 0.19 mm.Five planes with a distance of 1.00 mm were measured,and the average error of the measurement distance is 0.05 mm.

关 键 词：光学三维形貌测量 条纹投影 傅里叶变换轮廓术 双目匹配 

分 类 号：O439[机械工程—光学工程] TN206[理学—光学]