| 摘要 |
PURPOSE: To provide a lighting inverter apparatus for a high pressure discharge lamp, a metal halide lamp, etc., in which flucturation of light emission, that is so called an acoustic resonance phenomenan and caused in the case the high pressure discharge lamp is driven by high frequency output of the inverter. CONSTITUTION: The output of an inverter 3 is applied to a lamp 5 through a LC resonance circuit 4. The output of a sensor 8 to detect the discharge current of the lamp, a lower frequency square wave signal L to control the switching of polarity after discharge, and a control signal (a) to provide the necessary quantity of electric power to be supplied to the lamp are sent to an inverter control part 6. Before discharge of the lamp, the LC resonance circuit 4 is resonated to start discharging, and after discharge the LC resonance circuit 4 is made to function as a ripple filter, so that pulse string to apply square waves whose polarities change reciprocally to lamp electrodes is sent out. |
