Search

Effect of dichroic dye on nano particles induced homeotropic aligned liquid crystal (HALC) cells was studied for an enormous approach in display technology. The measurements of absorption coefficient and electro-optic (E-O) performance of HALC cells doped with two different concentrations (wt. /wt. ratio) of 0.25% and 0.5% of dichroic dye reveal that higher dye concentration lowered the values of threshold as well as operating voltages. However, contrast ratio (CR) and absorption coefficient (β) have been found to be reduced with higher dye concentration due to increase in off state transmittance. [ABSTRACT FROM AUTHOR]

Polymer dispersed liquid crystal (PDLC) is a striking material and have an enormous role in electro optic display devices. In this paper, nanoparticles (NPs) doped PDLCs in normal mode were prepared from a mixture of UV curable liquid polymer, nematic liquid crystal (LC) and silica NPs by the polymerization induced phase separation (PIPS) process. Morphological study shows the LC droplets cluster formation in pure PDLC and LC droplets with a more uniform phase separated polymer matrix in NPs doped PDLC due to the heterogeneous nucleation rate caused by the increased nucleation at the surface of NPs. Further, electro optic properties of doped and pure PDLC including transmittance, driving voltage, contrast ratio and sharpness as well as slope of the linear region of the transmittancevoltage were measured, compared and analyzed. Driving voltage of NPs doped PDLCs quite improved, however the slope of linear region and contrast ratio declined as compared to pure PDLC. [ABSTRACT FROM AUTHOR]

In this paper, the effect of doping of a fixed amount of dichroic dye on electro-optical (E-O) characteristics of vertically aligned liquid crystal (VALC) cell has been studied. In this experiment, VALC cells were prepared by polyimide (PI) coated glass substrates. A controlled amount of dichroic dye was uniformly mixed into host liquid crystal (LC) and mixture was filled to cell by capillary action at its isotropic temperature. The experimental results on phase behavior and electro-optic exposed the advancements in display properties of dye doped VALC cell with a significant reduction of isotropic temperature compared with the pristine VALC cell. [ABSTRACT FROM AUTHOR]