Reduced Power Consumption in a Single-Polarizer Reflective TN-LCD
Details
Recently, we clarified that a single-polarizer reflective TN-LCD with a two-sheet retardation film produces an achromatic image with high luminance and a high contrast ratio, even if the on-voltage of the TFT-LCD is reduced to 2V. The power consumption can thus be decreased to one-sixth to one-seventh of that of a conventional reflective TFT-LCD with a 5V on-state, while maintaining a high-quality image. In this paper, we numerically analyze the influence of the twist angle, the dispersion of Δn, and material parameters of an LC on the relationship between the electro-optical properties and the on-voltage to obtain the optimum twist angle and dispersion of Δn, and the lower limit of the on-voltage. We found that the optimum twist angle is about 50°, and that a small dispersion of Δn is preferable for obtaining a high-quality image. In addition, we clarified that the on-voltage can be lowered from 2V while maintaining a high-quality image when the LC material parameters are optimized.
