| 摘要 |
PURPOSE:To enhance the initial luminous efficacy as well as the life-performance characteristic after burning, by interposing a given thickness of silicon-dioxide film layer made of a given particle body, which provides a narrow of visible-rays transmittance-ratio. CONSTITUTION:The inner wall of a lamp glass 1 is coated with a silicon-dioxide film 2 and a fluorescent film 3, in that order. The silicon-dioxide film 2, which provides a visible-rays transmittance-ratio of 3-25%, is made of a silicon dioxide having a specific surface area of 30-270m<2>/g. The silicon-dioxide film 3 thus prepared enhances the initial luminous efficacy by 2%, and it also increases the life-performance characteristic after 3,000hr of burning by 3%. |
