Abstract
From the view point of universal design, a product and public sign should use colors which provide color distinguishability to some extent for all users of diverse color vision including color vision deficiencies and yellowing of a crystalline lens by age. At the same time, however, designers need to use colors which make a product or a public sign beautiful and aesthetic. In this research, we propose a systematic method of aiding designers to determine optimal n colors for a product and public sign which meet conditions both on color distinguishability for diverse users and on designer's aesthetic intentions. We confirmed the effectiveness of the proposed method by implementing it as a software, applying 13 colors representing 13 Tokyo subway lines in the route map, and obtaining the adjusted 13 colors of improved distinguishability for all of normal, protanope and deuteranope color vision.
