In the patterned vertical alignment ͑PVA͒ cell in which multidomains are formed from the perfect vertical alignment through an oblique field only, the formation of disclinations between liquid crystal ͑LC͒ molecules is inevitable in the presence of an electric field, which lowers transmittance and the response time. In the proposed PVA device, the pretilt angle is formed in four different directions through the polymerization of an UV curable reactive mesogen monomer at the surface. In this way, the reorientation of LC responding to an electric field is well defined, and thus the device shows reduced threshold voltage and much improved response time in all gray scales.

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Conventional multi-domain vertically aligned liquid crystal (LC) cells have defect points due to the collision of LC directors during the formation of multiple domains. In addition, the location of defects changes with time resulting in a slow response time. This paper proposes a robust vertically aligned LC cell, where the LCs are locked by polymer walls, and the azimuthal anchoring on the surface of the alignment layer is controlled by the polymerization of a UV curable reactive mesogen monomer. As a result, the defect points are trapped at a single position, resulting in a greatly improved response time.

Viewing angle control of a vertical alignment (VA) liquid crystal display using only one panel has been investigated. In conventional VA modes, LC director tilts down in four directions making 45 o with respect to crossed polarizers to give rise to wide viewing angle. By dividing pixel into two regions or RGBW structure and controlling the LC director to tilt down to the polarizer axes, the image quality in oblique directions can be controlled without distorting the image quality at normal direction. Also using light leakage in oblique directions, any type of information such as characters and image can be generated. This generates extra image over a main image in oblique viewing directions, that is, the original image is overlapped with made image when the voltage is controlled to the extra pixel for viewing angle control.

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