Frequency-dependent electro-optics of liquid crystal devices utilizing nematics and weakly conducting polymers

摘要

Conducting polymer films acting as both electrodes and alignment layers are very promising for the development of flexible and wearable tunable liquid crystal devices. The majority of existing publications report on the electro-optical properties of polymer-dispersed liquid crystals and twisted nematic liquid crystals sandwiched between highly conducting polymers. In contrary, in this paper, electro-optics of nematic liquid crystals placed between rubbed weakly conducting polymers is studied. The combination of weakly conducting polymers and nematics enables a frequency-dependent tuning of the effective threshold voltage of the studied liquid crystal cells. This unusual electro-optics of liquid crystal cells utilizing nematics and weakly conducting polymers can be understood by considering equivalent electric circuits and material parameters of the cell. An elementary model of the observed electro-optical phenomenon is also presented.