COLORED FLUORESCENT LAMP CONSISTING OF DOUBLE TUBE

摘要

PURPOSE:To obtain a colored fluorescent lamp with high efficiency and without environmental pollution by providing a coaxial outer tube made of glass that is thicker by 4 to 24mm. at the outside of an inner tube made of a fluorescent lamp with a normal metal cap on both sides and then a pigment layer on the inner circumferential surface of the outer tube. CONSTITUTION:A bulb 21 made of glass with excellent optical transmission is used as an outer tube 20 and a pigment layer 22 is formed by coating the inner circumferential surface with organic pigment. A lamp 10 used for an inner tube has a normal metal cap on both ends and a phosphor layer 12 is provided on the inner circumferential surface of a bulb 11 made of glass. The inside diameter of the outer tube 20 is formed thicker by 4 to 24mm. than the outside diameter of the inner tube 10 and a colored fluorescent lamp made of a double tube that is coupled coaxially is formed. In addition, an ultraviolet suppression layer is provided on the outer circumferential surface of the inner tube 10 or an inorganic pigment layer that absorbs ultraviolet rays such as titanium oxide or yellow titanium oxide between the bulb 11 of the inner tube 10 and the phosphor layer 12 can be provided. Moreover, the phosphor layer 12 can fixedly mix the inorganic pigment that absorbs ultraviolet rays such as titanium oxide or yellow titanium oxide and phosphor. As a result, the fluorescent lamp can be provided with high efficiency and non-environmental pollution.