FLUORESCENT LAMP AND ITS MANUFACTURING METHOD, AND ILLUMINATING APPARATUS

摘要

A fluorescent lamp (1) comprises a bulb (2) and bases (6). The bulb (2) is composed of bent portions (2c) and straight portions (2b) adjoining the bent portions (2c). The portions (2c, 2b) are formed by heating and bending bent-portion-forming portions of a straight bulb (2a) having a bulb outside diameter of 12 to 20 mm and a bulb length of 800 to 2500 mm. The straight portions (2b) lie in the same plane, with the bent portions (2c) interposed between the straight portions (2d). The bulb (2) has a pair of ends (2d) near each other where electrodes (5, 5) are so sealingly provided that a discharge path is formed from the straight and bent portions (2b, 2c). A phosphor layer (4) is formed on the inner surface of the bulb (2), and a discharge medium containing mercury is sealed in the bulb (2). The bases (6) are provided at both ends (2d, 2d) of the bulb (2). The thermal degradation of the fluorescent layer (4) formed in the straight portions (2b) is reduced, and the initial luminous flux deterioration is reduced, enabling operation of the florescent lamp with high efficiency. With such a constitution, a small fluorescent lamp that can be operated with high efficiency and has an improved light output characteristics and an illuminating apparatus using such a fluorescent lamp can be provided.