PS-VA (Polymer-Stabilized VA) is one of the mainstream technologies for TV display application. The market trend was once pursuing fast switching time to cope with 3D fever. However, during recent years, the demand of 3D is shrinking while the trend of high resolution is more and more prominent. Transmittance of the display is one of the key properties which is directly impacted so that the demand of high transmittance display and corresponding materials becomes stronger and stronger. We will present Merck’s latest LC materials and RMs development status for the advanced TV applications.

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Cholesteric liquid crystal displays are suitable for color e-papers because of low power consumption and good color characteristics. To stabilize the cell gap of flexible cholesteric LCD based on plastic substrate, polymer wall formation in the LC layer using PIPS (polymerization induced phase separation) method has been developed. Planar state is in general more stable than focal conic state in cholesteric LCDs. If an electrically uncontrollable LC area with absence of electrodes in passive matrix cholesteric LCDs has planar texture, it causes decrease of contrast ratio. We tried to make the cholesteric LCD with more stable focal conic state than planar state by formulating an appropriate monomer-liquid crystal mixture.

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Weak anchoring of Liquid crystal is highly desired in liquid crystal display devices because it decreases the switching voltage and improves display performances. The creation of such liquid crystal systems is an important goal for the next generation displays including polymer-stabilized blue phases (PSBPs). However, achieving weak anchoring in practice is proved to be difficult. Here, we report a new method of weak anchoring for LCs in contact with uniquely designed non-liquid crystalline side-chain copolymers, featuring both mesogenic and non-mesogenic units. The mesogenic pendant of polymers enhances the compatibility with the LC molecules, while the non-mesogenic part reduces the possible azimuthal anchoring energy of the mesogenic side-chain on LCs. LCs in a glass plate cell coated with these side-chain non-liquid crystalline copolymers showed anchoring transitions and weak anchoring interface formation at precise temperatures. The weak anchoring nature of LCs on copolymer surfaces was confirmed by their easy response to an applied magnetic field. Interestingly, significant decrease of operating voltage was achieved (~ 25 %) with this method in PSBPs while preserving the electro-optic performance of LCs at the same time. We therefore suggest that this unique method of producing weak anchoring might find application in the next generation liquid crystal displays.

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Random lasers are featured with low spatial coherence duo to multiple scattering in resonant. We used partially ordered liquid crystal as scattering medium and fabricated a liquid crystal based fiber random laser. The speckle contrast from random laser was below 0.04.As a result, we fabricated a speckle-free light source.

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