| 研究生: |
張瑞顯 Chang, Jei-Hsien |
|---|---|
| 論文名稱: |
應用線性迴歸診斷法於液晶顯示器Mura缺陷自動化檢測之設計與實現 TFT-LCD Mura Defects Automatic Inspection system using Linear Regression Diagnostics Model |
| 指導教授: |
陳響亮
Chen, Shiang-Linang |
| 學位類別: |
碩士 Master |
| 系所名稱: |
電機資訊學院 - 製造工程研究所 Institute of Manufacturing Engineering |
| 論文出版年: | 2005 |
| 畢業學年度: | 93 |
| 語文別: | 中文 |
| 論文頁數: | 147 |
| 中文關鍵詞: | 液晶平面顯示器 、線性迴歸診斷法 、自動光學檢測 、Mura缺陷 |
| 外文關鍵詞: | Mura defect, Automatic inspection, Regression diagnostics, TFT-LCD |
| 相關次數: | 點閱:88 下載:11 |
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TFT-LCD模組製程的面板點燈檢測除基礎的光電響應量測之外、還包括壽命(aging)及畫質缺陷檢測,如點、線、異物、Mura…等缺陷,然而在諸多的畫質檢測中,尤其以Mura缺陷之瑕疵最不易檢測出來,而易招致客戶抱怨,不為消費者所接受。目前產業界的Mura缺陷檢測判定,皆於成品階段以人工目視之方式進行全面檢測,人工檢測除了費時之外也容易造成漏檢、誤判等問題,因此建立自動化產品的檢測機制是絕對必要的。
本研究深入探討TFT-LCD顯示原理,分析各種Mura缺陷的形成原因,依據缺陷之特徵進行分類,並蒐集相關文獻及學理,建立一套檢測程序。檢測方式分別以面掃描CCD攝影機模擬人工視覺檢測的情形,在約110公分的距離下,使用高解析度的鏡頭來檢測整塊面板的品質。並以自行撰寫的Mura缺陷檢測程式及建構檢測硬體之架構,完成Mura缺陷的自動化檢測系統。Mura檢測方法主要利用數位影像處理之技術,分別以線性迴歸診斷及預測偵測影像中異常值(Outliers)及影響點(Influential point),以Niblack's閥值切割進行Mura缺陷區域的分割,再進一步量化評價備選Mura,並以0.5的辨識臨界值判斷出每一個真實的Mura缺陷。
本文實驗使用了13片17吋TFT-LCD面板產品,其中有10片panel經由人眼目視方式檢測出Mura缺陷(bad panel),另外有3片panel經由人工檢測判定無任何缺陷之正常品(good panel)。經自動化檢測結果顯示本研究使用的方法皆可有效正確地分類出良品(G品)與不良品(NG品)的TFT-LCD面板產品。
The Liquid Crystal Display(LCD) nowadays will be the most important and promising technical product. The techniques of inspection of the LCD panel include aging, final display inspection , and final visual inspection. Line, poin , particle, and Mura etc. are those of the display defects of the LCD panel. However, the Mura defect on TFT-LCD is most difficult to inspect among all the known defects and thus it is prone to be complained by customer. Currently, most of TFT-LCD Mura defect inspection tasks are done by artificial inspecttion, which is time-consumption and low accuracy. Therefore it is essential to build up an automatic inspection scheme of the manufacture process and with the image processing techniques to attain a high accurate detection rate.
The presented method of the TFT-LCD Mura defects inspection is mainly with digital image process, which consists of three phases. The first phase, we employ regression diagnostics method to detect outliers and influential points, and then to estimate background image region. The second phase, we segment candidate region Mura from TFT-LCD display image using Niblack's threshold. In the third phase, we quantify Mura level for each candidate, which is used to identify real muras while the mura level threshold was set to be 0.5.
The experiment has been performed on 13 TFT-LCD panel samples consisting of 10 bad panels and 3 good panels. Each bad panel has at least one Mura defect. All Mura defects in our experiment were detected by human visual inspection in the field beforehand. Good panels are claimed to have no Mura defect. Finally, in the manner of the presented visual inspection technique of Mura defect in TFT-LCD, all Mura defects claimed by human inspection have been correctly detected and classify the good panels(pass) and the bad panels(fail) successfully.
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