液晶顯示器用之配向布品質檢測技術探討

Evaluation of Rubbing Cloth For Alignment of Liquid Crystal Molecule

劉玉玲(Uo-Lin Liu)

指導教授 ： 黃振球

元智大學/工程學院/化學工程與材料科學學系/碩士(2011年)

摘要

本文利用定向刷磨配向 (Rubbing Alignment)機制，探討利用滾輪 (Rubbing Roller)旋轉方向的不同、改變不同的滾輪轉速得到不同摩擦強度 (Friction Strength)與使用配向布毛的表面平整度的不同之配向布進行配向處理，組裝成為液晶盒 (Liquid Crystal Cell)，使用預傾角量測儀、偏光顯微鏡、彩色分析儀、液晶電壓驅動與穿透率量測系統、錨定能量測儀來比較預傾角 (Pre-tilt Angle)和對比度 (Contrast Ratio)之趨勢及觀察液晶之配向特性。

研究方向一中利用配向布毛的表面不同，進行配向處理，探討配向布毛的表面不同所呈現出的效果與配向性。研究二中利用滾輪滾速的不同達到不同的刷磨強度利用摩擦強度公式計算RS = NΛ(2π rω / v−1) N：摩擦次數 Λ：壓入量， r：滾輪半徑， ω：滾輪轉速， ν：位移平台的前進速度。得知轉速越高的到的摩擦強度越強並討論最佳機台參數。研究三中為利用滾輪旋轉方向的不同達到順毛方向刷磨與逆毛方向刷磨，刷磨次數為一次、三次、五次、十次、二十次，個別進行液晶盒的組裝與量測。

上述實驗結果得知，配向布毛表面經修剪後達到平整之配向布其對比度優於無修剪處理的配向布毛表面不平整之配向布，其穿透率的強度也是有處理優於無處理之配向布此實驗中滾輪轉速越高摩擦強度也越強其所得到之液晶 (Liquid Crystal)預傾角也隨著升高，而在偏光顯微鏡下液晶盒均無暗態漏光 (Dark State Light Leakage)，且配向均勻，對比度也隨著摩擦強度的升高而增加。
進而研究研在順毛方向與逆毛方向之差異，實驗中順毛方向刷磨配向製程所得之對比度優於逆毛方向刷磨配向製程，而對比度的高低可以判斷顯示器品質優劣。

關鍵字

定向刷磨配向 ； 摩擦強度 ； 預傾角 ； 對比度 ； 液晶 ； 穿透率 ； 配向布

並列摘要

In this study, directional brushing with the system, explore the use of rollers rotate direction, to change the different roller speeds are different friction strength and use the distribution to the fabric surface structure is different to alignment treatment assembled a liquid crystal cell , using the pre-angle measuring device, polarized light microscopy, color analysis, LCD voltage drive and transmittance measurement system, water droplets to compare pre-angle observation system and contrast and observed the trend of liquid crystal alignment properties.
Studies using a different wheel rotation direction to clockwise and counterclockwise brush brush grinding mill grinding brush as a number of individual assembly for liquid crystal. Of two-speed rolling using rollers of different brushes to achieve different grinding intensity strength by friction formula RS = NΛ (2π rω / v-1) that the higher the speed the stronger the strength of friction. Study III used with different structures to the surface of cloth, were assigned to the treatment of the surface with different structure to the cloth which demonstrate the effect and with isotropic.
Experimental results, one in a clockwise direction in the study were assigned to the brush grinding process is better than counter-clockwise from the contrast with the brush grinding process, and display contrast level of quality can be judged the merits and thermal stability good. Of two friction in the rotational speed of the higher they get, the stronger the intensity of the LCD with the pre-tilt angle also increased, while the liquid crystal cell under the microscope in polarized light no dark state light leakage, and with the uniform, the contrast also with the increasing of friction strength. Surface structure of the three treatment results of the contrast is better than no deal with the surface of the cloth, the strength of its transmittance is better than no treatment in dealing with the cloth.

並列關鍵字

Rubbing Alignment ； Friction Strength ； Pre-tilt Angle ； Contrast Ratio ； Liquid Crystal ； Rubbing Cloth

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