在压力测试时, 高分辨率TFT-LCD(Thin Film Transistor-Liquid Crystal Display)液晶面板会发生“斑点不良”。为了预防该不良的发生, 本文分析了“斑点不良”的发生机理: 压力测试时, 隔垫物PS(Photo Spacer)发生滑动, 将阵列基板上透光区域的配向膜-聚酰亚胺PI(Polyimide)划伤, 而失去配向液晶能力, 在暗态画面下, 划痕处会发生漏光, 形成斑点状。本文对不同尺寸及分辨率的液晶面板进行了压力测试, 比较隔垫物挡墙、黑矩阵BM(Black Martrix)、隔垫物站位等不同因素对“斑点不良”的影响: 隔垫物挡墙能有效阻挡隔垫物的滑动距离的23.6%, 能有效降低“斑点不良”的漏光发生; 当隔垫物滑动的距离未超出黑矩阵的遮挡范围时, 不可见“斑点不良”或很轻微; 站在金属块(Pillow)上的隔垫物比没有站在Pillow上的隔垫物滑动距离小约10%。最后以49 in超高清UHD(Ultra High Definition)液晶面板为例, 提出一种改善 “斑点不良”的的设计方案: 增加PS上下挡墙设计, 降低PS 滑动距离; 增加BM 宽度设计, 保证PS边缘到BM边缘的距离大于PS滑动距离; 降低PS的个数, 增加PS的大小设计降低透过率损失。该方案客户验证无“斑点不良”发生且透过率下降1.2%, 说明此设计方案能够有效地改善“斑点不良”。

When we proceed pressure test on TFT-LCD(Thin Film Transistor-Liquid Crystal Display) panels with high resolution, “spot issue” always occurs. PS(Photo Spacer) slides from Gate metal line to transparent area and scratches PI(Polyimide) film, so that LC(Liquid Crystal) molecules can’t be anchored. At Dark Picture, place where PI film is damaged occur light-leaking, and forms “spot issue”. In order to prevent this issue, we carried out pressure test on TFT-LCD panels with different size and resolution and compared the designs of Photo Spacer, Barriers, BM CD(Black Matrix Critical Dimension) and PS standing Position. We find that the sliding distance of PS can effectively reduce 236% by PS Barriers, so light-leaking risk effectively decrease. When PS sliding distance is not beyond the scope of BM(Black Matrix), “spot issue” is not invisible or very slight. The sliding distance of PS standing on the Pillow made by metal block is smaller than that without standing on the Pillow about 10%. At last, taking an example of 49 UHD(Ultra High Definition), we put forward an effective prevention of "spot issue" design of LCD: Increasing the PS Barriers design to reduce the sliding distance of PS; Increasing the width of BM CD make sure the distance from PS edge to BM edge being greater than PS sliding distance; Reducing the number of PS and increasing the size of the PS design reduce the transmittance loss. The results of client authentication do not occur “spot issue” and transmittance fell by 1.2%, which shows that this design scheme can effectively improve the “spot issue”.