基于数字图像处理的导光板网点分布检测

The Detection of the Backlight Pattern Distribution Basing on Digital Image Processing Methods

导光板是侧入式液晶背光中的重要组件,其输出光场面亮度的均匀性与导光网点的分布密切相关。本文针对利用激光打点制备的导光板,使用墨水和酒精处理网点所在的表面,使网点位置与非网点位置形成灰度对比;使用相机采集导光板网点面的图像,通过图像处理,包括二值化处理、灰度反转、边缘腐蚀、连通域重心坐标获取及透视校正等操作,获得网点的位置信息、密度分布信息。基于数字图像处理的导光网点检测方法可应用于导光板的生产检验中。

The light guide plate is an important element of the backlight for liquid crystal display. The brightness uniformity of the output light field is closely related to the backlight pattern distribution. In this study, the distribution information of light scatting dots fabricated by laser directly drilling was detected basing on digital image processing methods. In order to improve the gray scale contrast between scatting dots and the background, the textured surface was firstly processed by ink and alcohol. The photo of textured surface was then taken by a camera and processed by digital image processing methods including following steps: binary processing, gray scale inversion, edge corrosion, computation of pixel coordinates for connected domain geometric centers and perspective correction. The above-mentioned method for backlight pattern distribution detection has widely potential applications in the field of manufacturing and testing of light guide plates.