Study on Electro-optic Characteristics of Fringe-field Switching Twisted Nematic Mode using a Liquid Crystal with Negative Dielectric Anisotropy

We have studied 90$^{\circ}$ twisted nematic mode switching by fringe electric field(F-TN mode) using a liquid crystal (LC) with negative dielectric anisotropy. In the device, two polarizers are parallel each other, electrodes exist only on bottom substrate, and one of rubbing direction is coincident with polarizer axis. Therefore, the cell shows a black state before a voltage is applied. With a bias voltage generating fringe-electric field, the LC twists perpendicular to fringe electric field such that the LCs are almost homogeneously aligned except near the bottom surface since the negative type of the LC is used. Consequently, the new device exhibits much wider viewing angle than that of the conventional TN mode due to in-plane switching and relatively high transmittance since the LC director above whole electrode area aligns parallel to the polarizer axis.

유전율 이방성이 음인 액정을 이용한 Fringe-field Switching Twisted Hematic 모드의 전기광학 특성 연구