| 摘要: | 隨著液晶顯示器（Liquid Crystal Display；LCD) 技術不斷的進步，追求厚度薄、質量輕、高輝度與高均勻性兼具是目前發展的重點，而LCD須有背光源才能達到顯像功能，現在光源的應用發展已由以往的冷陰極管( Cold Cathode Fluorescent Lamp；CCFL)進步至發光二極體 ( Light Emitting Diode；LED)，而在大尺寸LCD的顯像中，要達到輕、薄的目的，最常使用的入光方式為側入光式，側入光式光源必須利用導光板 (Light Guide Plate；LGP)透過網點破壞全反射(Total Internal Reflection；TIR)的原理，將光源均勻的分佈在顯示區，而在大尺寸的網點製作目前業界主要是以印刷式方式進行。
本論文研究中，以現有19吋背光模組的量產水準均勻性81%~83%為基準進行改善(產品規格為中心值88%，下限值80%)，利用田口玄一的田口方法，透過魚骨圖及相關文獻，找出網點大小、油墨比例、油墨烘烤時間及油墨黏度等四個影響均勻性的主要控制因子，並選用L27直交表以有條理的方式進行分析，最後再依業界常用的可靠度測試 (Reliability Analysis；RA) 條件進行最終確認。
藉由本研究得到的最佳參數組合為: 網點直徑+10%、油墨比例20:1、油墨烘烤時間30分鐘、油墨黏度2200cps，實驗結果，信號雜訊比(S/N)較原設計值增加了4.4 dB，均勻性也由目前量產的81%~83%提高至88%~90%。
;Owing to the continuous progress on the technology of Liquid Crystal Display (LCD), the current technical development are focusing on pursuing the thinner thickness, lower weight, higher brightness and higher uniformity.
As we knew, the LCD device is capable of displaying the image on account of the backlight unit and the most general backlight unit people adopted has moved forward from CCFL to LED. In the big-size LCD device, to achieve the goal of thinner and lighter, the most popular type of incident light is the Side-Incident type. The Side-Incident illuminant should match up to the designed patterns upon the Light Guide Plate (LGP) to distribute the light uniformity and the current patterns upon the LGP are majorly fabricated by the printing method in Industry.
Based on the data provided from current mass production line, the general standard of light uniformity of 19” BLU (Back-Light Unit) is around 81% to 83%. In this thesis, the Taguchi Method, Fishbone Diagram and abundant work experiences are adopted to analyze the problem scientifically. By way of those tools and knowledge, the L27 Array and 4 control factories, Pattern Diameter, Ink Ratio, Baking Time and Ink Viscosity are selected to be the Orthogonal Array and Control Factors, respectively. In the final, the Reliability Analysis (RA) is used to validate the result.
According to the result of this thesis, the best parameter set is: Dot Diameters: +10%, Ink Ratio: 20:1, Baking Time: 30 minutes and Ink Viscosity: 2200 cps. Moreover, on the basis of the experimental result, the S/N ratio increased 4.4 dB in comparison with the original result and the uniformity raised from 81%~83% to 88%~90%. |
