TFT-LCD边缘暗带不良机理研究与改善

Mechanism research and improvement of edge dark band of TFT-LCD

针对薄膜晶体管液晶显示器(Thin Film Transistor-Liquid Crystal Display,TFT-LCD)边缘亮度偏低、出现暗带的不良现象,对不良机理及影响因子进行研究,并总结较优工艺条件。实验结果表明从液晶面板设计角度,均匀的边缘盒厚有助于提升边缘亮度均一性,故适中的液晶量、硅球尺寸、硅球掺杂比及较硬的封框胶其性能更优,同时贴附偏光片后的液晶面板越平坦其暗带程度越轻;从背光源角度,模组成品的边缘暗带不良与背光源批次存在强相关性,但主要受背光源的平坦度等尺寸参数影响而非背光源自身的暗带程度。此外,老化工艺释放了背光源与液晶屏组装时产生的内应力,缓和边缘位置的形变,适当延长老化时间有利于降低边缘暗带不良发生率。通过以上较优条件的导入,成功改善了TFT-LCD显示器边缘暗带不良,有效地提升了产品竞争力。

The undesirable phenomenon of edge dark band of TFT-LCD is introduced,the mechanism and influence factors are studied,and the optimum process parameters are concluded.The experimental results show that,from the perspective of panel design,the uniform thickness of edge cell gap is helpful to improve the uniformity of brightness in the edge area,and therefore the moderate amount of liquid crystal,the moderate size and doping ratio of silicon ball,and harder sealant are preferred.Meanwhile,the flatter the panel after polarizer attachment,the lighter the degree of dark band.From the perspective of backlight unit,the edge brightness uniformity of finished products has strong correlation with the batch of backlight.However,this is mainly related to the dimension parameters such as flatness of the backlight rather than the degree of dark band of the backlight.In addition,the aging process releases the internal stress generated during the assembly of backlight with panel,and alleviates the deformation at panel edge.Therefore extending the aging time appropriately is conducive to reduce the incidence of edge dark band.Through the application of optimum conditions,we have successfully improved the uniformity of edge brightness of our product and effectively enhanced its competitiveness.