| 摘要 |
PURPOSE: A mercury short arc lamp is provided to improve persistence and achieve an improved getter activation to the gas impurities inside of the discharge tube. CONSTITUTION: A mercury short arc lamp comprises a discharge valve provided with two electrodes, one electrode rod of which mounts a getter(7) consisting of niobium with the following two conditions met: D > 1.8.d andα>= 20°, wherein D and d represent respectively the diameters of the anode head(2) and electrode rod(4),αis the angle formed between the longitudinal axis L of the electrode and a hypothetical contact line(8) that connects a point P2 obtained by intersection of a line lying on the peripheral surface of the anode head in parallel with the longitudinal axis L and a vertical line(11) lying on the end of the anode head, and a point P1 on the edge of the end of the getter(7) in the opposite side with respect to the position of the anode head. |
