| 摘要 |
PURPOSE:To prevent a red light emission as well as to prevent a luminous radiation electron tube from going out owing to the heating shortage of a filament in a low light flux luminous output time, in the luminous radiation electron tube lighting device which lights a luminous radiation electron tube and dims it continuously in a wide scope. CONSTITUTION:The lamp voltage of a luminous radiation electron tube G lighted by a lamp power feeding circuit 1 makes a feedback to the lamp voltage feedback terminal 3 of a filament heating circuit 2, and when the lamp voltage is made into a level of strong red emission, the filament heating power is increases, and the lamp voltage is reduced, so as to prevent a red emission. When the lamp voltage is raised to the level of strong red emission, in a dimming, in a low temperature, in a starting, and the like, the filament heating power is controlled in the increasing direction, and thereby, it is effective to prevent a red light emission. |
