本論文針對機械視覺於銲點瑕疵檢驗之應用提出一套有效的解決方案。銲點瑕疵一直是電子工業界亟待解決的問題，而其遭遇之困難又可分為銲點表面的高度鏡面反射特性與銲點形狀的高度變異性等兩類。為了解決上述兩個問題，本論文可分成兩大步驟。首先是銲點檢驗的照明設計，利用銲點模型所合成的影像，以快速歸納出最適於銲點檢驗的照明方法，並在最後提出以入射角約為25°的單層環形光源作為照明形式。其二是真實銲點影像的特徵萃取與分類，論文中所提出之特徵組是由影像區域分割與影像區域平均亮度兩類所組合而成。
本論文研究具有下列特色：（1）所設計之照明方法不僅能明顯區隔不同類型的銲點影像，還能提供實際應用所需要的強健性與簡便性；（2）所提出之特徵分類法則不僅能準確的分辨出各類的典型銲點，尚能針對介於各類型間且易生混淆的銲點加以辨識。並且在無法避免此類銲點的實際應用場合裡，本論文所提之分類法則仍有95.16%的辨識率。基於上述結論，本論文的方法深具應用潛力。

This paper provides an efficient procedure for the application of machine vision in solder defects detection, which has long been a problem in electronic industry. The major issues of this task are unstable images due to specular reflection of solder surfaces and large variations of solder shapes. Thus, this paper is composed of two steps. The first one is the illumination design, through the simulation of solder surfaces, suitable illumination method could be induced by observing the synthetic images, and finally the adoption of a single-layer circular illumination with incident angle about 25°is concluded as the best illumination for extracting characteristic features from the images. The second stage is the feature extraction from real solder images under the designed illumination, and the feature set proposed includes the partitioned regions and weighted areas.
The major contributions of this work are: (1) The designed illumination can effectively and robustly highlight solder image features according to the solder types; furthermore, this simplified lighting can also help in speeding up lighting operation and/or image processing. (2) The proposed feature set and classification method can not only recognize typical solders precisely, but also identify the ambiguous solders sensitively. Even in the practical application involving ambiguous solders, the recognition rate of the proposed method remains as high as 95.16%. Based on these conclusions, this research has great potential in industrial applications.

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