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This paper investigates the voltage hysteresis effect and residual birefringence in the polymer-stabilized blue phase I and II, under various phase separation conditions. By irradiating samples with ultraviolet (UV) light and curing the samples at a reduced temperature, the polymer in the blue phase formed a compact network along the direction of the UV light irradiation. The dense polymer network pinned the cubic lattice structure of the blue phase enabling it to return to its original optical isotropic state. In this manner, hysteresis and residual birefringence were suppressed from 4.16% to 1.67% and 0.057% to 0.002%, respectively. Although the driving voltage remained high, the reduction in hysteresis and residual birefringence are precisely the advancements required for the accelerating development of blue-phase liquid crystal displays. [ABSTRACT FROM PUBLISHER]

- In this work, a low-hysteresis polymer-stabilized blue-phase LCD is developed by controlling the polymerization temperature and using a double-sided IPS (DS-IPS) electrode. Compared to a conventional IPS LCD, this DS-IPS LCD has a driving voltage of 45 V, which is lower than that, 62 V, of a conventional single-sided IPS LCD. The transmittance is increased approximately 23%. The hysteresis is reduced to 0.44% which decreases as a function of the operating voltage. Furthermore, simulations of the maximum transmittance and operation voltage associated with the offset between the electrodes in the top and bottom substrates were also evaluated. [ABSTRACT FROM AUTHOR]

Abstract: The study investigates the thermal hysteresis in the phase transition between the cholesteric liquid crystal and the blue phase of liquid crystal. Both the CLC phase and the blue phase can stably exist at room temperature and be switched to each other using temperature-controlled processes. Two sets of bistable conditions are demonstrated using various surface treatments. In a homogeneous aligned sample, two stable states, CLC with a planar alignment and blue phase with a uniform lattice distribution, reflect light of wavelengths 480–510nm and 630nm, respectively, as determined by the corresponding Bragg’s reflection conditions. In the untreated sample, the CLC phase with a focal conic texture can scatter light and the blue phase with a non-uniform lattice distribution provides high isotropic optical transparency. [Copyright &y& Elsevier]