液晶顯示器具有薄型化、輕量化、低耗電量、無輻射污染、且能與半導體製程技術相容等優點，使其在短短三十年間，產品上的應用更呈飛躍性的成長。在液晶顯示面板(LCD)的製造過程中，須於兩片玻璃基板之間的空隙注入液晶，而基板間的空隙則是利用噴灑間隙物(Spacer)來達成，間隙物之特性在於保持玻璃基板之間的液晶厚度均一性，其作用在於防止液晶厚度不均所產生顯示影像模糊之缺失，因此LCD面板的間隙均一性是由珠狀(Bead)間隙物的大小及其分佈位置來決定。一般使用噴灑式珠狀間隙物(Ball Spacer)製程，此噴灑過程可能造成珠狀材密度不均而影響模組平坦性，進而影響整體畫質表現。目前檢測間隙物分佈位置之方法是採取人工透過顯微鏡來目測間隙物數量(密度)及是否有重疊情形發生，本文將利用影像處理之技術，將檢測系統自動化，透過工業相機取得影像，並將影像經過一連串的檢測處理，最後將輸出檢測結果及間隙物數量(密度)，此方法有效地提升了檢測效率及準確率。
本論文結合了自動化對焦與LCD間隙物計數與檢測兩大部分，實現LCD面板間隙物自動化檢測系統。首先透過自動對焦取得間隙物分佈位置的清晰影像，並利用本文所提出之區域式值方圖等化 、二值化與連通物件法檢測LCD面板間隙物計數及是否有錯誤(重疊)情形發生，誤差率在1%以下。最後將結果透過wxWidget GUI and OLE輸出於螢幕與Excel中。

After thirty years of liquid crystal display (LCD) development, the applications of LCDs have grown quickly and have wide application. LCD has the following features: thin, lightweight, low power, less EM radioactive, compatible with semiconductor processing technology. During the manufacturing process of liquid crystal display panel, manufacturers have to inject liquid crystal between the front and rear pieces of glass after injecting spacer which is used to maintain the cell gap (the distance) between the front and rear pieces of glass. It will cause the blurred image displayed on the LCD if the thickness between two glass plates is not equal. Usually the detection of spacer is manually to count the number of spacer and check the overlapped problem of spacers through a microscope. To solve this issue with automatic machine vision, an image processing technology is developed in this thesis.
In our system, we capture images from an industrial microscope-capability camera, and then a detection processing algorithm is used to process the images to determine if the image is a focused one. Our method greatly improve the efficiency and accuracy. In our system, we integrate an auto-focus with the LCD panel spacer’s count and detection. There are three main steps:
1) Capture clear images by using an auto-focus algorithm.
2) Count the number of spacer and detect if they are overlapped or not by applying region histogram equalization, binarization, and connected component image processing algorithms. Experiment show that the error rate is under 1%.
3)Use wxWidget GUI to display the result (the output from step 2) on the monitor. Moreover, we use OLE to save the result in an Excel file for further processing and archiving purpose.

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