| 摘要 |
PURPOSE: To improve luminescence efficiency of a fluorescent lighting system to be employed for a planar light source so called as a side light type. CONSTITUTION: Mercury and a rare gas such argon gas at low pressure are sealed in the interior of a glass tube 11 whose inside is kept air-tight and which has either a linear shape or at least one curved part and discharge electrodes are arranged in both end parts of the glass tube 11 to compose a discharge lamp 18. A reflecting plate 20 to reflect ultraviolet-rays is installed in the outside of the glass tube 11 and a phosphor body 12 to convert the ultraviolet-rays to visible light-rays is applied to the face to which the ultraviolet-rays 16 emitted from the glass tube 11 and reflected by the reflecting plate 20 are radiated. Since not like a case of a conventional fluorescent lamp, the light-rays reflected and turned back to the inside of the tube are not absorbed in the phosphor layer, the luminescence efficiency is heightened. |
