薄膜晶体管液晶显示器(TFT-LCD)扭曲向列型(TN)液晶曲面显示器搭配宽视角偏光片暗态时会发生色不均现象, 推测色不均现象的发生机理为: 曲面状态时, 玻璃基板受应力发生形变, 面板中应力不均, 加之液晶双折射, 暗态时上视角观察显示屏上下两侧边缘发蓝。本文模拟了不同改善措施对色不均现象的影响, 同时对有改善的模拟结果进行了实验测试。测试结果表明, 可以通过两种方式改善色不均现象: 第一种是增加暗态亮度, 掩盖暗态时色不均现象, 如调整电路、偏光片吸收轴角度等。实验结果表明调整电路使显示器暗态亮度从0.18 cd/m2提升至0.25 cd/m2, 色不均面积由显示器面积的30%减小至10%, 吸收轴角度从135°调整至134.5°, 色不均面积减小至10%, 但电路调整使显示器响应时间增加2.5倍, 吸收轴角度调整0.5°会使对比度下降20%, 对产品性能均有不利影响; 第二种是改善曲面状态下显示屏内部应力均一性, 如增加液晶盒盒厚、高温老化、降低显示器玻璃基板厚度等。实验结果表明: 降低玻璃厚度至0.2 mm以及高温60 ℃老化72 h均能使色不均现象消失, 且对产品性能无不利影响。

Uneven phenomenon will appeare when TFT-LCD (Thin Film Transistor-Liquid Crystal Display) TN curve panel used with WV (Wide View) polarizer. In the curve state, the mechanism of uneven color is speculated that there is non-uniform stress inside the panel when it is forced bending. 812.8 mm(32 in) TN curve panel is used as an example to discuss and research the uneven color phenomenon. For the problem of uneven phenomenon, the paper proposes two effective methods to improve uneven color phenomenon: First, increasing dark state brightness, the uneven color phenomenon is covered. The experimental results show that the adjustment circuit makes the display dark state brightness increase from 0.18 cd/m2 to 0.25 cd/m2, and the color uneven area is reduced from 30% to 10%. But the circuit adjustment makes the display response time increase to 2.5 times. The angle of the absorption axis is adjusted from 135° to 134.5°, and the area of color unevenness is reduced to 10%, and the adjustment of the absorption axis angle of 0.5° will reduce the contrast by 20%, which is detrimental to product performance influences. Homogenizing the stress in the TN curve panel is the second method, this paper improves the color unevenness by experiments such as increasing the cell gap of the panel, high temperature aging, and reducing the thickness of the glass substrate of the panel. The experimental results show that reducing the thickness of the glass to 0.2 mm and aging at high temperature for 72 h can make the color unevenness disappear without adversely affecting the product performance.