When the fluorescent lamp, which is filled with low pressure krypton gas and saturated mercury vapor, is operated on a commercial ballast working at domestic frequencies, it has the characteristics as follows; as the electric power of the lamp is reduced at room temperature, it can sustain the light emission characteristics as same level as the general one. But if the ambient temperature around the lamp is lower than the room temperature, the fluctuation of light emission appears below the critical temperature, and the light emission is reduced remarkably. To investigate these defective phenomena of the lamp, authors studied the properties of the discharge voltage-current, the fluctuation frequencies and the wavelength of moving striations which depend on the ambient temperature at the constant pressure of the filling gas. As the results, authors obtained conclusions as follows.(1) The fluctuation of light emission behaves like as the positive moving striations.(2) The temperature at which moving striations appear is determined by a mole fraction and a mole number of kryptonmercury vapor mixture in the discharge tube.(3) These moving striations show the similar characteristics to “r”wave which based on the fluctuation of ion density in Ne discharge.(4) In this temperature region in which moving striations appear, the excitation of krypton gas is activated, and the light emission of mercury line decreases.
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