Abstract
This paper proposes a new color universal design method without restricting usage of colors and their combinations using dithering technique. A key idea is that a solid color and a dithering of darker and lighter colors to approximate the solid color may look as similar color by normal color vision whereas they could be distinguishable by color vision deficiencies because one is solid and the other is a pattern of dark and light colors. Efficacy of the idea is confirmed through some experiments.
