High Performance Negative Dielectric Anisotropy Liquid Crystals for Display Applications

We review recent progress in the development of high birefringence (Delta n >= 0.12) negative dielectric anisotropy (Delta epsilon < 0) liquid crystals (LCs) for direct-view and projection displays. For mobile displays, our UCF-N2 (low viscosity, negative Delta epsilon, high Delta n) based homogeneous alignment fringe-field switching (called n-FFS) mode exhibits superior performance to p-FFS in transmittance, single gamma curve, cell gap insensitivity, and negligible flexoelectric effect. For projection displays using a vertical alignment liquid-crystal-on-silicon (VA LCOS), our high birefringence UCF-N3 mixture enables a submillisecond gray-to-gray response time, which is essential for color sequential displays without noticeable color breakup. Our low viscosity UCF-N2 also enables multi-domain VA displays to use a thinner cell gap for achieving faster response time.