【作者】 陆艺；

【导师】 张涛；

【作者基本信息】 四川大学 ， 测试计量技术及仪器， 2003， 硕士

【摘要】 汽车前照灯的照明性能、配光性能对保障夜间的行驶安全是非常重要的。汽车前照灯的检测需要用“汽车前照灯检测仪”，而“汽车前照灯检测仪”的定期校准工作需要用“前照灯检测仪校准器”来进行；“前照灯检测仪校准器”是否合乎标准需要靠“前照灯检测仪校准器检定系统”来检测。 随着光电技术、半导体、计算机技术以及图像处理等高新技术的发展，光电非接触测量技术在测量领域的应用日益广泛，它改变了接触式测量在测量精度、测量速度等方面的不足，提高了测量的自动化和实时性。本文介绍了一种采用面阵CCD成像技术作为测试方法的汽车前照灯检测仪远近光校准器检定系统。此系统采用多维精密可调工作台，并利用计算机数字图像处理技术，以VC++编程实现，达到了自动测量出被测校准器的发光强度，远光中心坐标，近光拐点坐标以及光轴偏角等特征参数的目的。它的优点是测量精度高，重复性好，使测量实现了自动化。 在本论文中，首先介绍了关于灯光检测的一些概况和国家标准，以及本课题的技术要求，比较国内外常用的几种测量方法，提出了用CCD作为光电传感器来测量； 第二步对通过对灯光检测仪校准的测量原理、特点和实际测量中的具体要求进行分析，完成该测量仪的机构设计。首先提出了该测量仪的整体结构设计方案和主要组成部分，详细设计中的CCD的选用、光栅的选择、以及机械结构设计部分；CCD成像原理，完成了测量光路部分的具体设计；最后给出了整个测量的过程。 第三步介绍了数字图像处理的基本知识，包括调色板，灰度图，设备无关位图(DIB)等，并主要介绍了BMP文件的结构；以及图像处理中常用的一四川大学硕士论文些操作原理，例如滤波、二值化等等。 第四章提出了适合于本测量仪的图像处理方法和步骤，并给出了软件实现的方法。本软件系统满足了图像处理的目的，同时为进一步的图像处理方法研究提供了开发平台。然后给出了测量控制软件实现的方法，从而实现用计算机对整个测量过程和数据采集，处理的自动控制，TIFF格式图像的转换，生成等照度曲线图等，其中关键部分给出了源程序。 最后介绍了所进行的一部分实验，并对实验数据进行了分析，得到正确结论。同时通过理论误差分析和分辨力与测量范围的计算，得出了该测量仪器能够达到测量要求的结论。 总之，本光电检测系统是集图像数据采集、图像处理、图像显示于一体的高精度、高速度测量系统。它实现了车灯远近光的图像采集与测量。该测量系统理论方法的提出丰富了光电非接触领域的理论和方法，为车灯的空间非接触测量提供了借鉴作用。更多还原

【Abstract】 The lighting and light matching capability of the automobile headlamp is very important to the safety of night-driving .The measurement of automobile headlamp must use the headlamp measure instrument, which is needed to use a calibration instrument to calibrate. However, whether the calibration instrument is standard must be checked up by a measure system.With the development of Opto-Electronic Technology , semiconductor Technology , Computer Technology and image processing Technology, the photoelectric non-contact measuring technology was used more widely in the field of measurement, which has changed the shortcoming of the contact measuring method in precision and speed and improved realtime and automation of measurement. A measuring system for calibrators of headlamp tester for motor vehicle using planar array CCD as detector is introduced in the paper. It utilizes the computer digital image processing technology. And this system can measure the characteristic parameters automatically and quickly, such as luminous intensity, center of far light, corner of the close light. The advantage is high accuracy, good repetition and automatic measurement. It is proved in application that this system tallies with national standard of lamp performance measuring. Its virtue is the high precision, good repetition, making measurement automatized.In this paper, Chapter One introduced general situation and nation standard in the measurement of light, and the technological requirement of the system. Wecompared some measuring methods in our country and in the foreign country. So we offered the method of using array CCD as detector.In Chapter Two, through the analyzing for principle, characteristic and practical demand of the measurement, the structure design is been accomplished. In the first part, the blue print of the whole structure of the measuring instrument and main parts is brought forward. In the second part, the detailed design is brought forward. CCD imaging theory is expatiated, the concrete optical route is designed and analysis on choosing the main accessory is given. In the drive device system, detailed design on metrical element is processed and analysis on choosing the other accessories is given. For example, how we choose the CCD, and the grating. And how we design the structure of the mechaine. In the last part, the whole course of the measurement is advanced.Chapter Three introduced some knowledge of digital image processing, including palette, grayscale and DIB, but mainly talk about the structure of the BMP file. Also we mainly introduced image transform method that we often use. For example the filtering, binarization.In Chapter Four, the blue print of the whole structure of the software system and main parts is brought forward. The image processing software system can not only fit the purpose of image processing but also gives a stage for farther exploitation on image processing. In the third part, the method of software realization on measure-controlling is given out, so we can automatically control the measurement course, data collecting and data processing automatically, the transforming of the TIFF format, the produce of the equal illuminance curve. And in these, I gave the source program of the key part.At last, I chiefly introduced about the experiment that has been done, and analyzed the data, then brought out the elementary conclusion. At the same time, the conclusion that the instrument can fit the demand is gained, trough academic error analysis and calculation on resolution and measuring range.In conclusion, the photoelectric system for measuring the position of the hole on the surface of the sphere is a high speed and precision system, which is aorganic system of image data acquisition image processing image show. The principle of this photoelectric measuring system enrichs the measuring theory in the fileld of non-contact measurement and supply references to the measuring of the headlamp.更多还原