Recently, LED light sources are becoming popular with the general lighting, such as offices, houses and shops. We can control easily the spectral distribution of the LED light sources, compared with the traditional light sources such as incandescent lamps, fluorescent lamps and so on. This article reports that we established spectral characteristics in order to develop LED light sources which improve the appearance of facial skin color, one of the important visual targets in lighting design. We conducted a subjective experiment with a novel index of the preference of facial skin color "PS" under various CCT (correlated color temperature) and D_<UV> (the distance from the blackbody curve for the color temperature) conditions. The results show that the best ranges of PS and D_<UV> differ depending on CCT. It is also found that the key spectral component for preferred appearance of facial skin color is in the range between 570 and 580 nm. Based on the result, we developed a series of new LED lighting fixture.
