激光在PVC表面直接标刻二维条码的研究

发布时间：2018-04-04 10:31

本文选题：激光直接标刻　切入点：二维条码　出处：《山东大学》2015年硕士论文

【摘要】：现今激光直接标刻技术已经在很大程度上取代传统的标刻工艺,成为未来信息追踪的重要方式。PVC材料涂装工艺复杂,激光直接标刻技术非常适用于该种材料表面的直接标刻。本课题从影响加工的工艺参数、劣质条码的图像处理两个方面入手,做了以下研究工作：研究了功率、扫描速度对条码深度的影响规律。从脉冲能量角度,推导了标刻深度与功率、扫描速度的理论模型,并通过实验对该模型进行修正,确定了深度与功率、扫描速度的关系式。统计不同深度下的条码识别时间,得到识别时间较短条码的深度范围,确定激光器操作参数的范围。选取对条码识别影响最大的对比度及印刷增长率为条码图像评价指标,针对影响PVC管材表面标刻条码质量的功率、扫描速度、线间距、偏焦量四个工艺参数,采用控制变量法,每个激光参量取5水平,研究了各参数与评价指标之间的关系。利用效应曲面法,采用星点实验设计了30组实验,以对比度、X及Y方向的印刷增长率为评价指标,利用二阶非线性模型对各个工艺参数进行模型拟合,而后对四个工艺参数进行参数优化,最终确定了5组优化后的工艺参数。在此基础上,通过研究条码深度对管材力学性能的影响,最终确定一组PVC管材表面标刻条码的最佳工艺参数组合。对采集到的条码图像选取合理的去噪方法对图像进行滤波去噪,选取合适的二值化方法对不同图像质量的条码二值化处理,采取图像增强技术对表面出现划痕的条码进行信息修复,采取条码重构技术对破损相对严重的条码进行条码图像信息增强,通过上述图像处理技术的选用,完成条码的识别过程。本文的研究成果对于激光标刻二维条码在PVC上的应用具有重要的指导意义,对于激光直接标刻其它非金属材料也具有一定的实际意义。
[Abstract]:Nowadays, the laser direct marking technology has largely replaced the traditional marking technology, and has become an important way to trace information in the future. The coating process of PVC material is complex. The laser direct marking technology is very suitable for the direct marking of the surface of this kind of material.This paper starts with the process parameters of processing and image processing of inferior bar code, and does the following research work: the influence of power and scanning speed on the depth of bar code is studied.From the angle of pulse energy, the theoretical model of marking depth, power and scanning speed is deduced, and the relationship between depth and power and scanning speed is determined by modifying the model through experiments.The recognition time of bar code at different depth is counted, and the depth range of short bar code is obtained, and the range of operating parameters of laser is determined.The contrast and printing growth rate, which have the most influence on bar code recognition, are selected as the evaluation index of bar code image. The control variable method is used to control the four process parameters, such as power, scanning speed, line spacing and focusing amount, which affect the quality of barcode marking on the surface of PVC pipe.The relationship between each parameter and the evaluation index is studied at the level of 5.By using effect surface method and star experiment, 30 groups of experiments were designed. With the printing growth rate of contrast X and Y as the evaluation index, the second order nonlinear model was used to fit the process parameters.Then the four process parameters were optimized and five groups of optimized process parameters were determined.On this basis, by studying the effect of bar code depth on the mechanical properties of the pipe, the optimal process parameters of a group of PVC pipe surface marking bar codes are determined.The image is filtered and denoised by selecting a reasonable denoising method for the bar code image collected, and the barcode binarization processing with different image quality is carried out by selecting the appropriate binarization method.Image enhancement technology is adopted to repair the information of the scratched bar code on the surface, and bar code reconstruction technology is adopted to enhance the image information of the seriously damaged bar code. Through the selection of the above image processing technology,Complete the bar code identification process.The research results in this paper have important guiding significance for the application of laser marking two-dimensional bar code in PVC, and also have certain practical significance for laser direct marking of other non-metallic materials.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TP391.44;TN249

【相似文献】