| 摘要 |
PURPOSE:To stabilize discharge by returning the bright point even if the bright point on an electrode shifts from the top of the electrode at instantaneous restart. CONSTITUTION:A high-tension pulse voltage application control means CR1 is provided, which applies high-tension pulse voltage to a high-pressure discharge lamp LA continuously for a certain time even after the lighting of the high- pressure discharge lamp LA. Since the high-tension pulse voltage is applied continuously for a certain time to the high-tension discharge lamp LA even after the lighting of the high-pressure discharge lamp LA, the electric fields become the strongest at the tops of both electrodes of the high-pressure discharge lamp LA, and pulse discharge occurs at the tops. Hereby, the tops of both electrodes get in the conditions that electrons are easy to come out, and even if the bright point does not exist at the tops of the electrode, the bright points recover to the tops. Accordingly, the discharge of the high-pressure discharge lamp LA can be stabilized, and the flicker and the going out of the high-pressure discharge lamp LA can be prevented. |
