PROBLEM TO BE SOLVED: To provide a lighting device in which an object to be irradiated is seem to be illuminated with white light while having red light of near 660 nm which is most suitable for growing a plant as a main light source.SOLUTION: The lighting device emits mixed light of red light, green light and blue light wherein the red light is a light contained in a wavelength region of 630-680 nm, and a ratio of photosynthesis photon flux density of the red light (R), the green light (G) and the blue light (B) based on a total 100% of each color of photosynthesis photon flux density is set to be R:G:B=60-80%:10-30%:5-15%.COPYRIGHT: (C)2013,JPO&INPIT【課題】植物育成用に最適な660nm近傍の赤色光を主光源としながらも、照射対象が白色光に照らされているように見える照明装置を提供する。【解決手段】赤色光と緑色光と青色光との混合光を発する照明装置であって、前記赤色光が、630~680nmの波長領域に含まれる光であり、前記赤色光(R)と前記緑色光(G)と前記青色光(B)との光合成光量子束密度の比が、各色光の光合成光量子束密度の合計100%に対して、R:G:B=60~80%:10~30%:5~15%であるようにした。【選択図】図3
