| 摘要 |
PURPOSE:To enhance the efficiency of light emission, by hermetically enclosing an excited light emission gas and a metal vapor having its ionization voltage near the optimal excitation voltage of the gas, to excite the atoms of the gas in a space between a cathode and an anode to emit light. CONSTITUTION:A cathode 3 and a reticulate anode 4 are disposed in a light- penetrated tube 1 so that the distance between the cathode and the anode is shorter than the mean free path of electrons. The inside surface of the tube 1 is coated with a fluorescent substance. An excited light emission gas of mercury or the like and a vapor of a metal such as cesium, which has its ionization voltage near the optimal excitation voltage of the gas, are hermetically enclosed in the tube 1. A fluorescent lamp is thus constituted. Ionization for generating a low-ionized plasma to neutralize space charge behind the anode 4 is caused by using an ionized gas other than the excited light emission gas. The voltage for the anode 4 is thus lowered to control the electrons to the optimal energy level to heighten the efficiency of light emission.
|
