PURPOSE: To obtain a light source which has a high luminous efficiency and a shape similar to that of an incandescent lamp by specifying the length of an electric discharge path formed between a pair of electrodes by the sectional area of inner tubes.
CONSTITUTION: The largest length of an outer tube bulb 1 is supposed to be H (cm), the average inner sectional area of inner tubes 6 and 7 is supposed to be S (cm2), and the shortest length of an electric discharge path formed between a pair of electrodes is supposed to be l (cm). The length (l) is adjusted to within the range of 2S+12≤l≤26S+10 when H is below 15 and S≤0.9, and to within the range of 2S+12≤l≤5S+29 when H is below 5 and S≥0.9. A1WA8 represent points at which flickering begins to develop, and it is necessary to adjust the sectional area (S) to over these points. A small fluorescent lamp which can be substituted for an incandescent lamp with luminous efficiency of 15 lumen/watt, is required to have luminous efficiency of over 30 lumen/watt from the economical point of view including manufacturing cost. In addition, it is necessary to adjust the practical length of the outer tube to below 15cm. The above specifications are obtained from straight lines indicated in a graph in which the vertical axis represents l and the lateral axis represents S.
YAMAZAKI HITOSHI
TAKEDA TAKAO
YAMAMOTO HIROJI
ITOU HIROSHI
IMAI JIYUN
| JPS52154283A | 1977-12-21 | |||
| JPS5444370A | 1979-04-07 |