PURPOSE: To generate a pulse in a phase easy to start an electric discharge lamp and perform a stable and certain starting lighting by generating a starting pulse having a large pulse energy with moving the generating position every cycle of the electric source voltage.

CONSTITUTION: When an electric source 7 is applied, a main condensor CM is charged in the first positive half wave, and a voltage in which the charged voltage of the condensor CM is added to the half wave voltage is applied to a switching element 9 in the following negative half wave. When the voltage exceeds a breaking over voltage VBU, the element 9 is connected to send the charged current rapidly to a pulse generating condensor Cp, which generates a high pulse Vps by the resonance effect with a secondary coil 5 of a leakage transformer 1. In the following positive half wave, the condensor CM is again charged, and in the next negative wave, the voltage is reached to the breaking over voltage in an advanced phase PC by the charged voltage of the further charged condensor CM to send a current to the element 9. In the similar way, the charging is advanced every positive half wave to move the electric phase forward. When the charging is completed, the progress of the phase is stopped, but the pulse is continued till the lamp 8 is started.