基于差分成像的激光光束指向性控制  

Laser Beam Pointing Control Based on Differential Dual-View Imaging

作　　者：杨红伟[1,2] 杜益冕 吕立冬 陶卫 卢俊国[1] 赵辉[1] Yang Hongwei;Du Yimian;Lu Lidong;Tao Wei;Lu Junguo;Zhao Hui(School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;School of Electrical and Information Engineering,Anhui University of Technology,Ma'anshan,Anhui 243032,China)

机构地区：[1]上海交通大学电子信息与电气工程学院,上海200240 [2]安徽工业大学电气与信息工程学院,安徽马鞍山243032

出　　处：《中国激光》2021年第17期72-79,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(51977001)。

摘　　要：激光光源的方向抖动是激光三角位移传感器测量误差的重要来源。为了抑制光源光束抖动,设计了一种基于差分成像的激光光束指向控制装置。该装置由一个准直激光器和两个接收透镜组组成,其中两个接收透镜组关于发射激光光束的光轴对称,每个接收透镜组由一个聚焦透镜和一个光电电荷耦合器件组成。激光光源光束抖动角度控制在0.4°以内时,成像在两个光电探测器上的激光光束的质心的均值可控制在误差许可的范围内。实验结果表明,采用该装置,拟合误差的估计标准差由28.53μm减小至0.2532μm,重复性精度由原来的±0.7 mm降低至±5μm,非线性误差由全量程的±0.8%减小至全量程的±0.04%。Objective As a displacement measurement tool,laser triangulation displacement sensors(LTDS)are widely used in industrial detection because of their noncontact nature and high accuracy.The optical path of LTDS is illustrated as follows:a collimated laser beam is projected onto the detected object and the diffuse reflected light is focused by a receiver lens onto a charge-coupled device(CCD)detector.When the detected object is moved along the direction perpendicular to the optical axis of the source laser beam,the reflected light beam spot(image spot)focused on the CCD will move correspondingly.Thus,the displacement over which the detected object moves can be calculated using ageometric optical model that is related to the image spot displacement.Laser-beam dithering is considered one of the major error sources in laser applications.To solve this problem,many averaging methods have been proposed.However,methods that can image two image spots on one CCD with a single image system are ineffective at improving the error factor of the laser beam directional instability.In other methods,structures comprising prisms or reflectors for producing two differential optical paths have been proposed.With those methods,the positional average of two image spots remains constant irrespective of the angle by which the source laser beam dithers.However,an installation error might be introduced,for which calibration is not possible because it is related to the laser dithering angle.Methods In this paper,a laser beam pointing control-based dual-view for laser triangulation displacement sensors(DVLTDS)is proposed.The structure comprises a collimated laser,two receiver lenses,and two CCDs,where the two receiver lenses and two CCDs are symmetrically arranged around to the optical axis of the source laser beam.DVLTDS generates two beam intensity distributions(BIDS)on two CCDs simultaneously.It converts the centroid movement of each BID into the detected object displacements through averaging.Hence,if the relationship among the optical par

关 键 词：几何光学 激光三角位移传感器 激光光束指向性 差分成像 

分 类 号：O436[机械工程—光学工程]