PURPOSE: To increase the luminous intensity of an ultraviolet ray, eliminate the need of using mercury, and solve a social problem by sealing at least one type each of discharge rare gas and halogen gas in a light emitting tube.

CONSTITUTION: At least one type of rare gas selected from xenon Xe, argon Ar, krypton Kr, Neon Ne or the like, and at least one type of a halogen group element selected from bromine Br, iodine 1, chlorine Cl, fluorine F or the like are sealed in a bulb l. In the case of a mercury-less discharge lamp so fabricated, when a sinusoidal wave high frequency of 20kHz, for example, is supplied across external electrodes 3 and 4, silent discharge resembling many whiskers occurs on the internal surface of a tube wall. At this discharge process, local micro glow discharge takes place on the internal surface of the tube wall and immediately disappears. Also, another type of micro glow discharge occurs at other points and immediately disappears. The aforementioned micro discharge is generated over the whole of the internal surface of the tube wall, thereby providing silent discharge, as if discharge were taking place evenly as a whole.