负性VA-LCD视角特性研究

Research on Viewing Angle Characteristics of Negative VA-LCD

液晶材料具有双折射效应,因此偏振光在液晶材料中各个方向上发生双折射的程度不同,这决定了LCD的视角特性和对比度随视角的变化有所不同。用光栅光谱仪测量在不同电压驱动下负性VA-LCD的电光特性,以及测量其电光特性随视角的变化;并对其三基色的电光特性和视角特性进行分析。结果表明,三基色的透过率在驱动电压2.2 V之前很小;在2.2 V后,透过率随电压的升高而增大;其中红基色和绿基色的透过率是一直升高,在电压达到5.0 V后,就是趋于平缓,而蓝基色的透过率是在3.7 V左右达到最大,而后慢慢变小,最后在电压达到6.0 V后,趋近一个稳定值。负性VA-LCD三基色的视角特性:红基色的视角范围最宽,绿基色次之,蓝基色的视角范围最窄。

Liquid crystal material has birefringence effect, so the polarized light occurs at different levels of bi- refringence in all directions in liquid crystal material, which determines the viewing angle characteristic and the contrast of LCD are different along with the change of viewing angles. The electro-optical characteristics of the nega- tive VA-LCD under different driving voltages and the electro-optical characteristics along with the change of view- ing angles are tested by a grating spectrograph to analyze electro-optical characteristics and viewing angles of the three primary colors of the negative VA-LCD. The results show that the transmittance of three primary colors is low under 2.2 V driving voltage, when the driving voltage exceeds 2.2 V, the transmittance increases with the increase of the voltage. The transmittance of red and green primary color increases all along, and reach 5.0 V are leveling off, but the transmittance of blue primary color is the maximum at 3.7 V, then become smaller, and then tends to a sta- ble value at 6.0 V. In the viewing angles of the three primary colors of the negative VA-LCD, the viewing angle coverage of the red primary color is the widest, and the viewing angle coverage of the green primary color is wider and the viewing angle coverage of the red primary color is the narrowest.