基于成像型亮度计的车灯配光性能检测系统研究

Study on Light Distribution Test Based on Imaging Luminance Meter

针对传统的转台式车灯配光检测系统结构复杂、检测成本高、耗时等问题,本文提出了一种基于成像式亮度计的车灯配光性能检测系统。该系统采用CCD传感器,通过光学系统获取车灯光照的强度,并以数字图像的形式显现出来;通过检测近光图像的明暗截止线将配光图像划分为强光区和弱光区,以两台通光孔径不同的CCD相机分别进行检测,同时调整相机的曝光时间,扩大传感器感光的动态范围;分析确定光源亮度和数字图像像素灰度之间的关系,最后根据像素的灰度值判定待测点的亮度。实验结果表明:在误差允许的范围内,成像型亮度计可以代替传统的转台式配光检测系统。该系统检测操作简单,检测速度快,稳定性好。

Aimed at the disadvantage of traditional light distribution test system which includes structural complexity,cost expensive and time consuming,this paper proposes a new method to test light distribution based on imaging luminance meter. The system adopts CCD sensor to get light intensity which is shown by digital images. And detects cut-off line of lower beam light which is used to devide light distribution area into intense light region and low light region. The system uses two cameras with difference apertures to detect these areas respectively. In order to enlarge dynamic range of sensor sensitivity,the system adjusts exposure time automatically. The system identifies relationship between the luminance of the measurement pionts and the gray-level of the image pixels. According to the gray-level of the image pixels, the illumination of detection points are detected. Experiments show that the proposed system can instead of traditional test system range of allowable error. The proposed system is simple,rapid detection,low cost and stable operation.