Evaluation of cutoff characteristics in oscillating liquid crystal molecules under sinusoidal electric fields

Sinusoidal electric fields are applied to liquid crystals (LCs) across various frequencies ranging from 0.1 Hz to 10 kHz to investigate the oscillatory behavior of LC directors. In a 1.5 mu m thick 5CB cell, a significant decline in refractive index change occurs in the frequency range greater than 10 Hz, in which the LC director cannot sufficiently follow the rapid fluctuations in field intensity. To evaluate the response speed of the LCs under sinusoidal electric fields, the cutoff frequency is introduced as a response indicator. Enhancement of the cutoff frequency can be achieved through conventional fast response techniques such as polymer-stabilized LCs.