Measurement of the Sum (e_1 + e_3) of the Flexoelectric Coefficients e_1 and e_3 of Nematic Liquid Crystals using a Hybrid Aligned Nematic (HAN) cell

摘要

A hybrid aligned nematic cell (HAN) is often used to measure the sum (e_1 + e_3) of the flexoelectric coefficients e_1 and e_3. However, a HAN cell has the difficulty of an internal offset voltage (internal bias) caused by the homeotropic alignment. We present a method to determine the internal bias and then take it into account in the flexoelectric measurement.