| 摘要 |
PURPOSE:To alleviate and eliminate unstable waving of arc by arranging both electrodes in a high pressure discharge lamp on a line in almost horizontal direction. CONSTITUTION:A pair of electrodes 2 of a high pressure discharge lamp 1 are arranged on a line in almost horizontal direction. Both electrodes 2 of high pressure discharge lamp 1 are exposed within a luminous tube 8 filled with gas and a high frequency voltage output from a high frequency inverter 11 is applied to both electrodes. Since both electrodes 2 are arranged on a almost horizontal line, a floating force is applied to the arc 4 due to the difference between gas density in the arc 4 and gas density in the vicinity of arc 4 and the center part of arc 4 is energized upward with an external force F resulting from the floating force. Namely, if the arc 4 is caused to move downward, since an external force F is applied, the position of arc 4 is almost fixed and waving of arc 4 can be prevented. |
