Viewing angle switching in vertical alignment liquid crystal display by optimizing pixel structure and controlling LC orientation

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° 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.