External electrode type fluorescent lamp

摘要

The fluorescent lamp has a glass tube 1 on the inner surface of which a phosphor film 2 is provided. A discharge medium including at least a xenon gas is enclosed in the glass tube. An inner electrode 3 is sealed at least at one end of the glass tube 1 through which a lead terminal 4 is led out. An outer electrode 5 composed of a conductor wire 5a which is wound spirally around the outer surface of the glass tube 1 along almost the entire length. A heat shrinkage resin tube 6 coats the outer surface of the glass tube 1 including the outer electrode 5. The creeping distance along the surface of the glass tube surface between the portion where the lead terminal 4 is led out of the glass tube 1 and an end portion 5b of the conductor wire 5a composing the outer electrode 5 is selected as at least 2 mm.