Electrical Properties of Liquid Crystal Cells*

Liquid crystals are ubiquitous electro-optical materials. Their applications include liquid crystal displays, tunable optical components such as filters, lenses, waveplates, and shutters, to name a few. As a rule, the tunability of liquid crystal devices is achieved by applying electric fields across mesogenic materials resulting in a reorientation of liquid crystals. Ions present in liquid crystals in small quantities can alter this reorientation and compromise the overall performance of liquid crystal devices. Therefore, research into the electrical properties of liquid crystals is very important because it allows the identification of materials suitable for particular applications. Electrical properties of liquid crystals are studied using liquid crystal cells. In this talk, we discuss how interactions between ions and substrates of a liquid crystal cell can affect the measured values of DC conductivity. Because of these interactions, the measured DC conductivity of liquid crystals can depend on the cell thickness. Important information about ions in liquid crystals can be deduced by analyzing this dependence.