| 摘要 |
PURPOSE:To lower start-up voltage as well as raise the keepability of luminous flux while reducing impure gas to a minimum by adsorbing impure gas generated in a luminous tube body in a getter metal housed in a branched tube separately provided. CONSTITUTION:The quartz glass luminous tube body 4 is connected to the branched tube 6 in which the getter metal 5 is housed to form the luminous tube 7. Gas in the tube 7 is exhausted from the opening of the tube 6, and then a metal halide, mercury, and a rare gas are enclosed in the tube and the opening of the tube 6 is sealed. Then, when a voltage is applied to the electrodes 2 and 3 to light it for approx. 5min, the metal halide (CeI3) is evaporated and decomposed into atomic state and remains in the form of impure gas, e.g., H2, O2, etc. after stopping of lighting in the tube 4. However, the impure gas is diffused and adsorbed in the metal 5 heated to approx. 600 deg.C in the tube 6. After the tube 4 is cooled and CeI3, mercury, etc., are restored from the tube 6 to the tube 4, the tube 6 is separated. Thus, a lamp having a low start-up voltage and a good luminous flux keepability can be obtained. |
