Abstract
Color vision deficient observers may not understand some of color names used in color-coding because, for example, they may put a different color name for a certain color, as they cannot discriminate some of colors. We investigated chromatic characteristics of dichromats, especially about their ability of color naming. In the experiment, observers answered names of color chips one by one in a random order in 3∼5 sessions. The observer could use a color name freely, but the name had to be one word. If one observer used the same name three or two times, these chips made the area of one categorical color in the coordinates of OSA color chips. These areas were compared between color normal observers and dichromats. There are some interesting differences. First, dichromats still use both of red and green in color naming. Results indicated, however, that dichromats have less number of categorical colors because some categorical colors were combined to one category (green & gray, pink & HADA (skin color), MIZU (water-blue) & purple, and orange & yellow). We expected that these differences were caused by the difficulty of color discrimination on the red-green direction. Even so, it should also be expected that by using some cues like difference of luminance (brightness), dichromats still can answer the color names including red and green reasonably.
This work was basically supported by the Regional New Consortium Projects from the Ministry of Economy, Trade and Industry of Japan (17C4020) and the Graduate School Sophistication Special Promotion Support by the Promotion and Mutual Aid Corporation for Private Schools of Japan to K. Shinomori.