HIGH VOLTAGE DISCHARGE LAMP

摘要

PURPOSE: To prevent the occurrence of cracks in quartz glass caused by a difference in expansion factors between the quartz glass and a tungsten electrode rod by covering the electrode rod of an electrode with a flexible woven hose made of heat resistant, insulating and inorganic material between a seal sheet and the melted end part of a glass ball throat. CONSTITUTION: Cylindrical throats 2 and 3 made of quartz glass are successively provided respectively in adjacent circular parts in the focus of a discharge glass ball 1. In both of the throats 2 and 3 of this glass ball, electrode parts 4 and 5 made of tungsten are sealed via molybdenum sheets 6 and 7 and buried by melting. The electrode rods 4 and 5 are surrounded by flexible woven hoses 21 and 22 made of knitted quart. The fabric of the woven quartz hose is made of SiO2 of 98% or more and the remaining is a rudimentary element containing an alkaline metal oxide and an alkaline earth metal oxide.