| 摘要 |
PURPOSE:To surely identify multi-step dimming without applying stimulation to eyes at the time of lighting by controlling an inverter circuit so as to gradually increase the light output of a discharge lamp. CONSTITUTION:A control means B controlling an inverter circuit A has an oscillating circuit 1 outputting the signal controlling the on/off of the switching element of the circuit A, a soft-start means D gradually increasing the light output of a discharge lamp la, and a soft-start means E quickly increasing the light output of the discharge lamp la. The oscillating circuit 1 is controlled by the output of the start means D until the light output of the discharge lamp la reaches a preset level after the operation of the circuit A is started by a switching means C, and the oscillating circuit 1 is controlled by the output of the start means E after the light output reaches the preset level. |
