P‐121: Electro‐Optical Properties of Inverse Twisted Nematic Cells with Different Pretilt Angles

Abstract

In general, the optical properties of any general twisted nematic cells consist of two complementary effects: LCbirefringent and LC-director-twist effects. In this paper, electrooptical properties of ITN cells without chiral dopants with different pretilt angles have been investigated for the first time to differentiate the LC-birefringent effect from the LC-twist effect. We have investigated transient responses of the ITN cell and found that the optical-bounce (LC backflow) effect of the ITN cell occurred in the transition from homeotropic-to-planar states under high applied voltages where the LC-twist-effect dominated. We have also explained the superiority of high contrast ratio of the ITN cell over the tilted homeotropic cell with same pretilt angle due to mutual compensation between two surface-LC layers adjacent to ITN-cell substrates in quiescent state. Author Keywordsinverse twisted nematic, ITN LC cell, electro-optical properties of inverse twisted nematic, or ITN LC cell. P-121 / C.-Y. Lin