摘要 |
A flash discharge tube includes a cylindrical glass bulb filled with a rare gas; a pair of main electrodes sealed to both ends of the glass bulb via bead glasses; rough surfaces formed at least in the regions to which the bead glasses are welded, the regions being on the outer circumferential surfaces of the pair of main electrodes; and hard microparticles adhered to the rough surfaces. The hard microparticles are embedded in the rough surfaces. This increases the connection strength between the bead glasses and the pair of main electrodes, thereby ensuring the sealing performance between the bead glasses and the pair of main electrodes. |