This paper experimentally investigates the dynamic characteristics of electrically controlled modulators based on liquid crystals (LCs) in the visible and near-IR regions and the effect of the electric-field parameters on them, along with the variation of the conditions of the interphase interaction of the LCs with the orienting surface. It is shown that it is effective to use a dual-frequency liquid crystal for phase and amplitude modulation of radiation with wavelength 1.55μm. In an LC modulator operating on the S effect, a 2π phase lag is obtained in a time of 2ms. The switching times can be reduced to the microsecond range when the twist effect is used and the LC layer is about 7μm thick by increasing the voltage from 30to50V.
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