基于刀口法的激光横向变形检测与标定方法
2018-07-26
作者：刘旭，黄承义
单位：武汉纺织大学
摘要：为测量材料的横向形变，提出了一种基于刀口法的激光横向变形检测与标定方法。通过控制遮挡板的精密机械运动来模拟刀口切割射向光电探测器的矩形光束，从而改变光电探测器接收的光照强度以检测光斑能量分布情况并建立光照强度与刀口运动位移的对应关系，最终根据位移与光强度的线性关系检测矩形光斑能量匀化状态并对移动的位移进行反向精确标定。试验得出：曲线交点坐标相对误差不高于1.63%，且遮挡板不同运动模式以及多点位实验中，矩形光斑中间1mm区域线性决定系数均为0.998，表明该方法可以借助精密控制的遮挡板的机械运动模拟材料的横向形变，为材料横向形变测量提供便利的检测模拟手段和方法。
关键词：刀口法；矩形光束；能量匀化；横向变形；变形标定
中图分类号：TG806；TH741；TN247文献标志码：A
Laser Transverse Deformation Detection and Calibration Method
Based on Knifeedge Method
Liu Xu，Huang Chengyi
Abstract:In order to measure transverse deformation of stressed material，a laser system that can detect and calibrate transverse deformations based on knifeedge method is constructed.Through accurately controlled mechanical movement of baffle plate that runs like a knifeedge across the rectangular light beam emitted by a diode laser generator，the intensity of laser light collected by photodetector is changed and the relationship of light intensity with moving displacement of the baffle plate can be established at the same time.An obtained linear relationship of the displacement with the light intensity can be used to explore the homogenization of the beam intensity.Precision displacement of the moving plate is used inversely to calibrate the linear relationship and the transverse deformation of the material.The experimental results show that the relative errors of the intersection coordinates of curves are not higher than 1.63% and the linear coefficient of determination of 1mm region in the middle of rectangular spot are 0.998 in the different motion modes and multipoint experiments of the baffle plate.It means that the laser system can simulate transverse deformation of material under the controlled precise movement of the baffle plate，and provides a convenient simulation method to the measure of transverse deformation.
Keywords:knifeedge method；rectangular light beam；homogenization of intensity；transverse deformation；deformation calibration