Investigation On The Properties Of Reconfigurable Liquid Crystal Polymer Template Via Visible-light Interference

Polymer-liquid crystal composites have aroused strong interest because of their good stability and regulation,as well as their application prospects in the fields of display,optoelectronics and biological medicine.As one of them,liquid crystalpolymer template system,has great flexibility due to the unique "wash-out/refill"characteristics,expanding the application range of polymer-liquid crystal composites.A variety of fancy optical devices based on this system emerge one after another,which breaks the traditional electric field regulation mode and realizes the diversified tuning of optical properties of devices.The holographic polymer-dispersed liquid crystal system based on light induced polymerization system has also been widely studied in the fields of optical switch,2D electrically controlled grating,naked eye 3D color hologram and optical sensor.With the increasing application requirements,we hope that liquid crystal optical devices can be applied to more and more complex scenes,and more stringent requirements are put forward for the simplicity of preparation,stability of structure and flexibility of performance.In this paper,the advantages of the two systems are combined.The polymerization source in the preparation process is extended from ultraviolet light to visible light,and the good reconfigurable properties are achieved.Based on these properties,two optical elements,reconfigurable holographic liquid crystal grating and distributed Bragg reflector(DBR),were fabricated respectively.The main contents include:1.The sample containing reactive mesogens(RMs)and visible light induced polymerization system is mixed,and the holographic liquid crystal grating is prepared through the double-beam holographic interference optical path.On the basis of in-depth study of the effect of the component distribution ratio involved in the polymerization reaction on the performance of the grating,the optical properties of the grating were studied.Based on the characteristics of "wash-out/refill",the dynamic reconstruction of the grating is realized by refilling the solvent,which is different from the traditional electric field regulation.2.An equilateral prism was used to simplify the holographic interference optical path.By treating the substrate with(3-mercaptopropyl)trimethoxysilane(MPTMS),the stable liquid crystal DBRs were prepared.The reflectance band of the film was adjusted by the content of ethanol,incident angle and intensity of incident light,and the mechanisms were also explored.Organic solvents were also used to reconstruct distributed Bragg reflectors,and the dynamic adjustment of optical properties was achieved.