Measurement of phase modulation time dynamics of liquid crystal spatial light modulator

Abstract

Liquid crystal spatial light modulators for precise dynamic manipulation of coherent light fields, used in diffractive optoelectronic optical data processing systems, are considered. This paper presents the results of a study of the temporal dynamics of the HoloEye PLUTO-2 VIS-016 liquid crystal spatial light modulator for analysis of light fields rate modulation. Experiments using binary phase computer generated holograms and binary focusing phase diffractive optical elements were conducted. Based on experimental data, the time characteristics of the modulator response were determined. It was found that when the rise time of the diffraction efficiency was 146 ms after the hologram displaying onto the SLM, and when switching to a new hologram, the decay time was 97 ms. These results allowed the dynamic generation of an alternating holograms at a refresh rate of 2 Hz with an interference level of –16 dB. Increasing the frequency of fringe pattern updates increases the level of interframe noise in the generated holograms, and when updated at the specification frequency, the generated distributions cannot be separated. Determining the actual frame rate based on the rise and decay times of the diffraction efficiency makes it possible to correctly calculate the minimum operating time of an information optical system containing a liquid crystal spatial light modulator.