| 摘要 |
PURPOSE:To prevent flickering by setting an operating time for both inverter circuits not to cause the output of light to be changed due to fluctuation of an electric discharge condition in dimming deeply. CONSTITUTION:An operating time for the first inverter circuit 2 is defined as t1 and an operating time for the second inverter circuit 3 is defined as t2. Also, the minimum high-voltage applying time necessary for reactivation or retainment of an electric discharge lamp is defined as ts, and a fluctuation arising time for an electric discharge condition during operation of the first inverter circuit 2 in dimming deeply is defined as tm. The operating time t1, t2 for both inverter circuits 2, 3 are set to hold t1+t2=T, ts<t1<tm. In this way, the operating time for both inverter circuits 2, 3 is set not to cause the output of light to be changed due to fluctuation of the electric discharge condition in dimming deeply. Flickering in deep dimming can be thus prevented. |
