Surface anchoring effect on guest–host ferroelectric liquid crystal response time – an electro-optical investigation

Abstract

2010) Surface anchoring effect on guest-host ferroelectric liquid crystal response time -an electro-optical investigation, Philosophical Magazine, 90:34, 4529-4539,The effect is reported of surface anchoring on various electro-optical parameters of a pure ferroelectric liquid crystal (FLC) and five mixtures with different concentrations of dye. The Anthraquinone D5 dye was used as guest entity, whereas Felix 17-000 was used as host in this investigation. The presence of dye molecules in the FLC dramatically affects the electrooptical properties compared with those of the pure system. Electro-optical parameters such as spontaneous polarization and rotational viscosity not only change with the addition of dye but they are also strongly dependent on the concentration of dye in pure FLC. The effect of dye molecules on the anchoring energy of the pure FLC system was also investigated. Due to strong anchoring energy on FLC substrate, its effect on response time was also studied. An improvement in the contrast ratio after dye doping was observed. The value of spontaneous polarization increases due to addition of dye, suggesting that molecular alignment improves, which is very useful from the application point of view.

Reduction of optical response time for fluorescent dye doped ferroelectric liquid crystal

“…The liquid crystal displays (LCDs) are more popular due to their low weight, thin shape and low power consumption. The displays based on Guest host mode can work in the active and the passive modes but the choice of guest material is vital for practical utilization of such Guest host LCDs [3,[5][6][7]. Passive full color LCDs consume appreciable electric power for back light systems.…”

“…The drawbacks of these FLC based display devices are their low brightness and energy deficiency due to the use of polarizers and absorbing color filters. The fluorescent Guest hosts LCDs are useful in the mobile communication tool which requires less energy [4][5][6][7]. Doping of fluorescent dye in pure FLC may be useful for enhancement of dielectric and electro-optical parameters.…”

Dispersion of fluorescent dye in the nematic liquid crystal: Enhanced photoluminescence and high birefringence

“…To enhance the optical parameters, dye may play a very much important role as a dopant. Communication tools which require less energy desire fluorescent guest hosts LCDs [11][12][13][14]. We can enhance different important parameters of NLC by doping fluorescent dye.…”