| 摘要 |
Disclosed is a lighting device which requires a low quantity of light or power-saving and applies a power-saving light source. The lighting device converts an alternating current electric power to one of a constant electric power state or a power-saving electric power state, and comprises a power source circuit for providing the alternating current electric power. A lamp can emit light with a lower quantity of light than the constant electric power state by the alternating current electric power in the power-saving electric power state. |
