RARE GAS DISCHARGE LAMP

PROBLEM TO BE SOLVED : To reduce flickering in light control of a rare gas discharge lamp. SOLUTION : The lamp is equipped with the rare gas discharge lamp 1 in which a pair of external electrodes 13a, 13b that exist along the axial direction are opposingly attached and arranged at an outer circumferential face of a glass bulb 12 sealing rare gas, a control circuit 20 for driving a transformer to drive the transformer so as to apply a unipolar pulse to an outside face electrode of this rare gas discharge lamp, and a light control circuit 17 constituted to light control brightness by reducing this lighting frequency in normal lighting of the unipolar pulse from this control circuit for driving the transformer and to control it at brightness of over 20% of that light control rate.