摘要 |
PURPOSE:To provide a dielectric barrier discharge lamp with high luminous efficiency, high tube wall load, and long life by forming at least part of a discharge container which also serves as a dielectric for dielectric barrier discharge and a light taking-out window material with a specific polycrystal alumina. CONSTITUTION:A discharge container 1 is made of about 350mm long polycrystal alumina and consists of an inside tube 2 and an outside tube 3 and the discharge gap of a discharge space 27 is about 5mm. The tubes 2, 3 serve as a dielectric for dielectric barrier discharge and a light taking-out window material, and electrodes 4, 5 made of a metallic net which transmits light are installed on the outside of the tubes 2, 3 respectively. The mean particle size of the alumina crystal is 1-2mum and impurities is 0.0005wt% or less. Excimer molecules are formed in the container 1 by dielectric barrier discharge. For example, when xenon gas is filled in the container 1 and a lamp is lit with a power source 20, even if 1.3 times power compared with use of synthetic quartz glass is applied, ultraviolet ray is efficiently radiated and the life is lengthened. |