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In the past in which Edison invented the electric lamp, the human had worked below the daylight, and took the meal and rested under the burn light in the night over one billion several years. Therefore, the human senses the color of foods illuminated by the burn light in the palatable color and the burn light is "comfortable light" by which the mind and the body are cured. The quality of light of the incandescent lamp is the homogeneity in the burn light. It is studied, in this paper, that the microcavity light source and the cluster light source are expected as light sources where luminous efficacy and lifetime are equal to the fluorescent lamp.