AUTOSTARTING SHORT ARC RARE GAS DISCHARGE LAMP

摘要

PURPOSE:To prevent molten fuse material, from sticking to an electrode by providing a metal foil fuse of a special sectional dimension and a special shape at the trunk part positioned on the same side of a positive electrode and a negative electrode in order to make a short circuit between the positive electrode and the negative electrode. CONSTITUTION:In a capsule 1 a negative electrode 2 having a conical top and a positive electrode 3 are fixed facing each other and a fuse 4 made of a metal foil or a metal wire whose sectional dimention is 1.25X10<-5>-3.14X10<-4>cm<2> is provided at a trunk part positioned on the same side of the positive electrode 3 and the negative electrode 2 to make a short circuit between them. Thus, an autostarting discharge lamp is formed. The fuse is provided under the condition of 0.04= r/l<=0.2 where the total length of the fusible part of the fuse 4 is lcm and the shortest distance from the top of the negative elec trode 2 to the fuse is rcm. Accordingly, starting property by fusing the fuse 4 becomes better and adhesive of fuse molten materials to the top of the negative electrode is prevented, thereby to improve brightness.