| 摘要 |
PURPOSE:To detect and control the temperature of a fluorescent lamp accurately by switching a heat quantity to the lamp on its way at warmup of the lamp. CONSTITUTION:A facial lamp heater 7 is fitted to the surface of a glass tube 23 of a fluorescent lamp 2 opposite to the side formed with an optical aperture 24 of the glass tube 23 and a thermister 8 as a temperature sensor is fitted to nearly the centre of the lamp heater 7. With the lamp 2 heated, since the lighting of the lamp 2 heats up itself at a low temperature at the start of warmup, the temperature of the temperature sensor is not excessively increased even when the thermal inertia of the tamp 2 is small. Moreover, when the temperature of the lamp 2 reaches a prescribed value or over, since the heating by the lighting of the lamp 2 and the lamp heater 7 are used at the same time, the lamp reaches the setting temperature in a short time. Thus, the temperature of the lamp is detected without error and the temperature of the lamp is kept accurately to the setting temperature. |
