| 摘要 |
<p>PURPOSE:To achieve long life of a discharge lamp. CONSTITUTION:An electron emitting material 3 is dry-blended with tungsten powder 2 which is a heat resisting metal powder of high melting point, which is treated by a hot hydrostatic pressure HIP treatment, and is impregnated to form an impregnated cathode material 4. The impregnated cathode material 4 is coated on or attached to a filament 7, and a hot cathode electrode 6 is formed. The electrode 6 is arranged on the end part of a discharge line 5. When the filament 7 is electrified and discharge is made with the impregnated cathode material 4 being heated, the electron emitting material 3 is protected by the tungsten powder 2 in the impregnated cathode material 4 against ion bombardment, and the life of the electrode is extended, and the life of a discharge lamp 1 is thus extended.</p> |
