APPROXIMATELY FLAT SMALL FLUORESCENT LAMP AND MANUFACTURE THEREOF

PROBLEM TO BE SOLVED: To provide an approximately flat small fluorescent lamp of compact type and low cost capable of generating high optical output by forming a light reflecting layer and a phosphor layer in a continuous concentric groove with two electrode laid therein for use as a lamp envelope, and fitting the envelope with a plate having one side coated with a phosphor layer. SOLUTION: An approximately flat small fluorescent lamp 100 is formed out of a glass envelope 11 and a circular glass plate 12. A continuous concentric (spiral) groove 17 is formed on the inner surface of the envelope 11, and two electron emission electrodes 14 with lead wires 13 are sealed into the groove 17. Furthermore, light reflecting layers with a phosphor layer as an uppermost layer are formed on the groove 17. On the other hand, the plate 12 covers the phosphor layer on the groove 17. Also, the plate 12 is sealed against an envelope peripheral part, but not against the upper surface of the side wall of the groove 17. According to this construction, a discharge generated across the electrodes 14 propagates along the path of the groove 17, and a phosphor emits a visible ray, with an ultraviolet ray absorbed from the discharge.