被动矩阵垂直配向液晶显示器光程差的表征与测量

Characterization and Measurement of Retardation in Positive Matrix Vertical Alignment LCD

在不加电场的情况下,被动矩阵垂直配向液晶显示器(PMVA-LCD)对于垂直入射光不产生相位延迟,故无法表征及测量其光程差。通过对PMVA-LCD透过率与电压关系的理论推导及模拟得出,在电压增大到一定值后,其透过率随电压增大而保持稳定,即此时光程差保持稳定,这一数值可用来表征PMVA-LCD的光程差。对实际样品进行测试,得到的结果与理论分析结果较为接近,之间的误差主要由白光的色散现象引起。根据此方法,可以方便地匹配液晶层的Δnd值与C-plate补偿片的补偿值R,使得PMVA-LCD达到更好的显示效果。

There is no retardation in positive matrix vertical alignment LCD（PMVA-LCD） for the vertical incident light, so it is difficult for positive matrix vertical alignment to characterize and measure the retardation LCD. This paper deduced and simulated the relationship of the transmittance and voltage. It was obtained that transmittance would keep stable if the voltage is high enough, that is, the retardation keeps stable, furthermore the retardation of PMVA-LCD could be characterized. The measurement results for the practical samples show that the simulation curves of relative transmittance in different voltage is similar to the testing curves, which errors mainly caused by the dispersion of white light. Based on this method, it is convenient to match liquid crystal layer and the retarder of C-plate on retardation, such that the PMVA-LCD would have a better performance.