Display fluorescent lamp and display device

Abstract

A display fluorescent lamp comprises; a dielectric cylindrical container having a large-diameter portion in which rare gas is sealed and a small-diameter portion which is almost coaxially connected with the large-diameter portion at one end of the large-diameter portion, the outside diameter thereof being smaller than that of the large-diameter portion; a light emitting portion which is formed at the other end of the large-diameter portion and has permeability; an internal electrode which is inserted into the cylindrical container from the other end of the small-diameter portion which is not connected with the large-diameter portion; a fluorescent substance layer formed on the inside face excluding that in which the light emitting portion is formed, of the large-diameter portion of the cylindrical container; and an external electrode formed on the outside face of the large-diameter portion excluding a portion in which the light emitting portion of the cylindrical container is formed, the length in the axial direction, of the small-diameter portion of the cylindrical container being set so as to be longer than an insulation distance required against a voltage to be applied between the internal electrode and the external electrode. Consequently, it is possible to ensure a sufficient insulation distance between the internal electrode and the external electrode even if the diameter of a glass valve is small.

Dependencies are inferred from the claim text.