| 摘要 |
PURPOSE:To realize a long service life by preheating each filament with a common preheating winding provided to filaments at the amalgam side of discharge lamps and heating each amalgam at the same time. CONSTITUTION:At the amalgam side filaments 11 and 21 of discharge lamps La1 and La2, a common preheating winding N is provided, and not only the filaments 11 and 21 are preheated by the common preheating winding N, but also the amalgams 12 and 22 furnished close to the filaments 11 and 21 are heated by the common preheating winding N. As a result, the temperature of the amalgams is made to an adequate temperature, the mercury vapor pressure is maintained at an optimum value, the illumination is stabilized, blackening is not generated, and the service life can be extended. |
