<p>The lamp device basically comprises a rare gas discharge fluorescent lamp (8) wherein rare gas is enclosed in the inside of a glass bulb (1) which has a fluorescent layer (2) formed on an inner face thereof and has a pair of electrodes (3) at the opposite ends thereof. It further comprises a high-frequency ac power source (19) and an electric voltage generating means to generate pulse-like voltage across a pair of electrodes (3) of the lamp (8) wherein an energization time of the puls-like voltage is equal to a half period of a wave form applied from ac power source (19) and the idle time integral-number times as long as the half period of the wave form applied from the ac power source (19). <IMAGE></p>
