多壁碳纳米管掺杂的聚合物分散液晶光栅的电光特性

Electro-optical characteristics of polymer-dispersed liquid crystal gratings doped with multi-walled carbon nanotubes

为了提高全息聚合物分散液晶的衍射效率以及降低其驱动电压和阈值电压,通过在聚合物分散液晶中掺杂多壁碳纳米管(MWCNT)研究其对H-PDLC光栅的电光特性的影响。本文采用了全息干涉的方法制备了4种质量分数(0,0.03%,0.05%,0.07%)MWCNT掺杂的H-PDLC光栅。结果表明MWCNT可以提升材料在532 nm处吸收率,从而导致掺杂0.05%多壁碳纳米管的H-PDLC光栅的一级衍射效率可以达到91%。同时引入MWCNT通过降低电阻率、增加电容改变了介质的介电性能,从而增强电场,表现为掺杂0.05%MWCNT时0.68 V/μm的低阈值电压和1.78 V/μm的低饱和电压。另外,随着MWCNT掺杂质量分数增加,H-PDLC的对比度逐渐降低。

In order to improve the diffraction efficiency of holographic polymer-dispersed liquid crystal and reduce its driving voltage and threshold voltage,the effect of its electro-optic properties on H-PDLC gratings was studied by doping multi-walled carbon nanotubes(MWCNT)in polymer-dispersed liquid crystal.In this paper,the holographic interference method was used to prepare four mass fraction(0,0.03%,0.05%,0.07%)of MWCNT doped H-PDLC gratings.The results show that MWCNT can increase the absorption rate of the material at 532 nm,resulting in the first-order diffraction efficiency of H-PDLC gratings doped with 0.05%multi-walled carbon nanotubes can reach 91%.At the same time,the introduction of MWCNT changed the dielectric properties of the dielectric by reducing the resistivity and increasing the capacitance,thereby enhancing the electric field.It shows a low threshold voltage of 0.68 V/μm and a low saturation voltage of 1.78 V/μm when doped with 0.05%MWCNT.In addition,as the MWCNT doping mass fraction increases,the contrast ratio of H-PDLC gradually decreases.