Research On Methods Of Improving Response Speed Of Thick Liquid Crystal Cell

As a photoelectric material,liquid crystal has been very mature in display application technology,but in the post-lcd era,its research direction gradually turns to other non-display electro-optical devices.The liquid crystal layer in the field of display is relatively thin,generally several microns,but the thickness of non-visible liquid crystal devices in the field of non-display can reach tens of microns or even hundreds of microns.The response time of liquid crystal devices is directly proportional to the square of liquid crystal layer thickness.Aiming at the problem of slow response speed of thick liquid crystal cells,we use various methods to design experimental schemes to improve the response speed of thick liquid crystal cells.In terms of theory,we firstly analyze and discuss the working principle of the existing liquid crystal cell,and determine the driving principle of the liquid crystal cell,and study the factors that affect the response speed of the liquid crystal cell,focusing on reducing the falling time of the liquid crystal cell.In the experimental aspect,solution 1,we use polymer-doped dual-frequency liquid crystal to increase the response speed of a thick liquid crystal cell;solution 2,we use the coplanar / opposite electrode conversion method to induce the directional growth of the polymer with an electric field and reduce the response time of the thick liquid crystal cell;option 3,we use the shear liquid crystal and side exposure method induce the directional growth of the polymer and improve the response speed of the thick liquid crystal cell.These experimental schemes are to induce the orderly growth of polymers,to form a two-dimensional fiber network along the surface of the liquid crystal cell,and to intersperse parallel fiber silk chains in the thick liquid crystal layer,so that the thick liquid crystal layers become thin liquid crystals layer superimposed in series.And the anchoring effect provided by the polymer alignment layer will allow the liquid crystal molecules to return to the initial state more quickly during the relaxation process,thereby reducing the response time of the thick liquid crystal cell as a whole.In order to reduce the response time of the thick liquid crystal cell,the fast response speed of the thick liquid crystal cell can be achieved.In the experiment,by comparing and measuring the response time of 5%,15%,25%,and 50% polymers with a thickness of 10 μm,30 μm,65 μm,we found that both the coplanar/ opposite electrode conversion method and the shearing liquid crystal and side exposure methods can reduce the response speed of the thick liquid crystal cell,and as the polymer concentration increases,the response time of the liquid crystal cell gradually decreases.In samples of different thickness prepared by coplanar/opposite electrode conversion method,the decrease time of polymer concentration of 5% and 50% is more obvious than that of experimental samples with polymer concentration of 15% and 25%.Compared with the coplanar / opposite electrode conversion method,the response speed of the shear liquid crystal and side exposure methods to experimental samples with different thicknesses and concentrations has been significantly improved.Based on the above research,these three experimental schemes provide theoretical and experimental basis for improving the response speed of thick liquid crystal cells and selecting different manufacturing methods and polymers with different concentrations.It has great research significance and reference value in the fields of terahertz,microwave,millimeter wave and centimeter wave with large phase delay.