| 摘要 |
<p>According to the present invention, a light-emitting element, a light-emitting device, and a lighting system, each of which has a broad spectrum like sunlight and has high color rendering properties, can be obtained. One embodiment of the present invention has a light-emitting device which includes at least two kinds of luminescence center materials, and at least one kind of the luminescence center materials is a quinoxaline derivative represented by the following general formula (1): wherein R1 to R4 are individually hydrogen or an alkyl group having 4 carbon atoms (a straight-chain structure or a branch structure).</p> |
