| 摘要 |
PURPOSE:To improve the contact between electrode members and an electron discharging substance by using an electron discharging substance which contains both scandium oxide, and at least one of tungsten and molybdenum, and subjecting the substance to a heat treatment carried out at 1,800-2,500 deg.C in vacuum. CONSTITUTION:In an electron discharging substance 18 prepared by mixing scandium oxide and tungsten, tungsten grains work like a binding agent since a compound which is made from both scandium oxide and tungsten covers the tungsten grains. As a result, the contact between the substance 18 and electrode members 15, 16 and 17 caused during the lighting of an electric discharge lamp is decreased. After the members 15, 16 and 17 are covered with the substance 18, they are subjected to a heat treatment carried out at 1,800-2,500 deg.C in vacuum so as to make part of the oxygen contained in the former scandium oxide to be eliminated. Consequently, semiconductivity develops in the former scandium oxide, and electron discharging performance of an electrode is improved. |
