| 摘要 |
PURPOSE:To indicate an exhausted lamp or lamps certainly and provide possibility of lighting without involving flicker of a normal lamp or lamps and/or drop of the light output by increasing and decreasing the energization power for a certain period of time, wherein the description concerns a device to light up a plurality of discharge lamps simultaneously. CONSTITUTION:Energization of discharge lamps is made with high frequency power generated by an inverter, and adjusting output therefrom and checking if there is any abnormal lamp, are made through a control circuit 2. Output limitation of inverter 1 is obtained by increasing its oscillation frequency. A discharge lamp assumes normal, abnormal, or gone-out as exhaustion of the lifetime in compliance with the frequency according to the two-end impressed voltage. The control circuit 2 consists of a timer 4, vibrator 5, PWM controlling IC 6, etc. The control shall limit the output until the applicable lamp will go out as exhaustion of its lifetime with checking of the lifetime display, while lighting of residual normal lamps is continued with an output which does not re-light the abnormal lamp after a certain period of time. |
