Generation of residual direct-current (DC) voltage (V_rDC) induces serious image sticking of liquid crystal displays (LCDs). In this study, a novel technique to determine the V_rDC of LC cells is proposed. We found that the V_rDC could be determined from a current-voltage (I-V) curve obtained by the application of triangular voltage. In the case of a vertically aligned twisted nematic (VTN) mode LC cell, where a vertical electric field is applied, the I-V curve shows maximum and minimum current peaks owing to rotation of an LC director, and the V_rDC is able to be determined from an average value of the two peaks. On the other hand, in the case of a fringe field switching (FFS) mode LC cell, where an in-plane (lateral) electric field is applied from comb electrodes, the current peaks derived from the rotation of the LC director do not appear. Therefore, we could not adopt the same way with that of the VTN mode LC cell. However, we found that there were two minimum current peaks derived from minimum capacitances of the FFS mode LC cell, and could determine the V_rDC by using these two current peaks. The proposed technique would be useful for the evaluation of the V_rDC of the LCDs, where the electric field is applied both vertically and laterally.

中文翻译：

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测定垂直和平面电场下液晶盒残余直流电压的新技术

残余直流（DC）电压（V _rDC）的产生会引起液晶显示器（LCD）严重的图像残留。在这项研究中，提出了一种确定LC细胞V _rDC的新技术。我们发现，可以通过施加三角电压获得的电流-电压（IV）曲线确定V _rDC。对于垂直排列的扭曲向列（VTN）模式LC单元，在其中施加了垂直电场的情况下，IV曲线显示了由于LC_指向矢和V _rDC旋转而产生的最大和最小电流峰值可以从两个峰的平均值确定。另一方面，在边缘场切换（FFS）模式LC单元的情况下，从梳状电极施加面内（横向）电场时，不会出现由LC指向矢旋转引起的电流峰值。因此，我们不能采用与VTN模式LC单元相同的方式。但是，我们发现有两个最小电流峰值是从FFS模式LC单元的最小电容得出的，并且可以通过使用这两个电流峰值来确定V _rDC。所提出的技术对于LCD的V _rDC的评估将是有用的，在LCD的垂直和横向都施加了电场。