| 摘要 |
PURPOSE:To make it possible to light with a specific power constantly with no variation of the lighting power of a discharge lamp by controlling the impedance voltage of the first winding responding to the impedance voltage of the second winding of a leakage type choke coil, and feeding a specific power to the discharge lamp. CONSTITUTION:A discharge lamp 8 connected to the other side of the first winding 41 of a leakage type choke coil 4, a detecting circuit 5 of the lighting power of the discharge lamp 8, a control circuit 10 connected to the detecting circuit 5 and to compare with a set standard value, and a semiconductor element circuit 9 driven by the control circuit 10 and connected to the second winding 42 of the leakage type choke coil 4 are provided. By controlling the impedance voltage of the first winding 41 responding to the impedance voltage of the second winding 42, a constant power is fed to the discharge lamp 8. Consequently, the discharge lamp 8 can be lighted at a specific power constantly with no variation of the lighting power of the discharge lamp 8. |
