2014 Volume 98 Issue 4 Pages 186-189
Various evaluation methods of color quality are proposed and discussed as alternatives or supplements of CRI. In this article, we show the result of optimization of color quality for landscape lighting based on feeling of contrast index (FCI). Color appearance of green, red and yellow plants was evaluated under 29 type illuminants. According to the result of experiments, higher FCI illuminants show the color of plants more attractively even if they don't have good CIE Ra values. On the other hand, too high FCI illuminants make unnatural appearance for 1/3 observers. So, there is optimal value of FCI for appearance of plants. The result shows that light sources which show the color of plants attractively can be developed by using FCI.