P‐106: Pretilt Angles and Liquid‐Crystal Director‐Deformation Profiles of Inverse Twisted Nematic Liquid Crystal Cells

Abstract

We have developed a simple optical method and analyzed data by extended Jones matrix method to obtain pretilt angles of invesed twist nematic (ITN) and tilted homeotropic liquid crystal (LC) cells. We have compared the measured pretilt angles of the ITN cell with those of an accompanying tilted homeotropic (ATH) cell. The results showed increasing discrepancies between them with increasing rubbing depth for LC alignments. However, these discrepancies could be explained by assuming that the surface-LC tilt angle of the ITN cell was equal to the measured pretilt angle of the ATH cell to generate a LC director-deformation profile within the ITN cell based on Oseen-Frank elastic continuum theory with infinite anchoring energy. The average of the LC tilt angles over this profile was equivalent to the measured pretilt angle of the ITN cell. Author KeywordsLiquid crystal deformation, inverse twisted nematic (ITN), pretilt angle of ITN cell P-106 / S.-Y. Wang SID 2014 DIGEST • 1387