Optimisation of resolution and color reproduction for color LCD by control of brightness and contrast levels

Usually LCDs (liquid crystal displays) have brightness and contrast controls. Because the optimal image quality depends on the choice of these controls, it becomes necessary to know how different combinations of the brightness and contrast levels influence the image quality. The image quality of a color display depends on both resolution and color reproduction. The resolution is determined by the spot size and SNR (signal-to-noise ratio) of the displayed image. Better resolution requires smaller spot size and higher SNR. The color reproduction is determined by the constant-channel chromaticity, the reproducible color gamut, and the luminance level of the white point. The faithful color reproduction needs the satisfaction of chromaticity constancy, large color gamut, and high luminance. Because the brightness and contrast controls affect the luminance and chromaticity of the background screen and signal screen, the resolution and color reproduction depend on their settings. Using a color LCD, we studied the optimized combination of brightness and contrast control to display the image with high resolution and faithful color reproduction.