Keypad Inspection System of Cellular Phone

In this paper we describe a keypad inspection of cellular phones using image processing. Before keypad buttons are assembled, they occur problems such as surface chipping, color difference, and font errors under process. To solve these problems and to improve the quality of the products, automatic keypad inspection is required. This paper deals with development of inspection method so that objects are moved and rotated for matching to reference image, when objects are in random direction and location in images. And then, for inspecting defect of keypad button, all images of the same patterns of keypad buttons are sequentially matched by the proposed method.