Dynamic response of shear horizontal wave propagating in liquid crystal cell to molecular reorientation

The dynamic responses of an acoustic phase to liquid crystal (LC) molecular reorientation in a shear horizontal (SH) wave device with an LC cell are measured by applying a voltage. The optical responses are also observed in order to determine the molecular director distributions in the device. The response of acoustic phase by removing the applied voltage is three orders of magnitude faster than the optical response. To investigate the effective viscosity acting on the SH wave propagation, the dynamic changes in the director distribution are calculated. Using the calculated director distribution, we obtain the effective viscosity acting on the SH wave propagation, which coincides qualitatively with the measured acoustic phase change.