FLUORESCENT LAMP AND LIGHT SOURCE USING IT

摘要

PROBLEM TO BE SOLVED: To reduce the quantity of enclosed mercury or improve a luminous flux retention rate. SOLUTION: By forming a phosphor film 4 on the inside surface of a light transmissive airtight container 1 in which a discharge medium containing a mercury vapor and a noble gas are enclosed and forming a protective layer 5 on the inside surface of the phosphor film 4 with multiple kinds of metal oxides of which starting materials (or introduction processes in conjunction with them) at the time of introduction are different from one another a barrier function to mutually make up for disadvantages in the case of individual use of the multiple kinds of metal oxides is provided, and mercury consumption and luminous flux degradation in a tube in conjunction with the elapse of lighting time can further be prevented as a whole.