关键词: 图像处理, 有机发光显示器（OLED）, 缺陷检测, 差影法, K-均值聚类

Abstract: Organic LED（OLED） screen often exists defects which have the characteristics of small size, low contrast, indifferent gray value. These defects will cause detection problem. Traditional thresholding method cannot detect the defects effectively. This paper proposes a multi-image-subtraction method to detect pixel defects of OLED screen. Based on the initial process of median filtering and image enhancement, the image is processed with pixel template extracting and subtraction operation, until a better contrast image is achieved. A K-means clustering method is selected to segment the image and detect the defects from the processed image. Through the tools of Labview and IMAQ Vision software package, this method proposed in the paper is implemented and verified by an OLED image. The test result shows that this method can detect defects effectively and the smallest defects can be 8 μm×8 μm.

Key words: image processing, Organic Light Emitting Display（OLED）, defect detection, subtracting method, K-means clustering