Electro-Optical Properties of Polymer-Dispersed Liquid Crystals Doped with Carbon Nanosolids

• Main Authors: You-Jhe Tsai, 蔡佑哲
• Other Authors: Wei Lee
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/38423156267948407374

碩士 === 中原大學 === 應用物理研究所 === 94 === Since the refractive index of polymer does not match that of liquid crystals in the polymer dispersed liquid crystal (PDLC) model, a light scattering phenomenon can be obtained in the absence of an electric field. On the contrary, the refractive index of polymer matches that of liquid crystals for a uniform direction of liquid crystals within each droplet in the presence of an electric field, meanwhile, reduction of light scattering can be attained and so the PDLC bulk achieves a transparent state. This promising device can be applied to large and flexible display panels without the need for alignment layers and polarizers. The suitable concentration of prepolymer to liquid crystal is investigated in the relevant literature to possess significant light scattering and then one can observe the electro-optical effect by employing an automatic measurement system (AMS). Experimental results show that the PDLC researched in the present thesis possesses the following characteristics: Firstly, threshold and driving voltage of the PDLC bulk is larger than that of intrinsic LC bulk due to the polymer doping of LC. A reduction of the threshold voltage can be obtained by adding C60 into the PDLC as a dopant. Secondly, if more prepolymer is added into the PDLC for a higher concentration, then a higher sensitivity to the variation of frequency results. The reduction of sensitivity to the variation of frequency can be obtained by adding C60 into the PDLC. Thirdly, PDLC doped with C60 can effectively reduce total response time in comparison with that of pure PDLC. Fourthly, the degradation of the off-axis haze phenomenon can be obtained while the effective refractive index of the PDLC doped with C60 is modified, furthermore, larger domains formed by the curing process relatively reduce the light scattering effect.