| 摘要 |
A light-emitting device includes a planar light-emitting unit having a light-emitting surface and a non-light-emitting surface, a planar solar power generator having a light-receiving part and a non-light-receiving part, and a rechargeable battery. The light-emitting unit and the solar power generator are arranged so that the non-light-emitting surface and the non-light-receiving surface face each other, thereby forming a light-electricity converter. The light-emitting device includes an orientation sensor configured to sense an orientation of the light-electricity converter, and a connection switch which is arranged between the non-light-emitting surface of the light-emitting unit and the non-light-receiving surface of the solar power generator, and which is configured to selectively connect the rechargeable battery to either the light-emitting unit or the solar power generator. The connection switch is configured to connect the rechargeable battery: to the solar power generator when the orientation sensor detects that the light-receiving surface of the solar power generator in the light-electricity converter faces toward a first direction; and to the light-emitting unit when the orientation sensor detects that the light-emitting surface of the light-emitting unit in the light-electricity converter faces toward the first direction. |
