Abstract
A rare gas fluorescent lamp, which has a pair of external electrodes, is widely used as a means for image illumination in offices. However, few studies and reports have been conducted on this lamp. Thus, we examined its energy balance. What we found was that over 90% of the lamp input power changes into thermal energy. To improve the luminous efficacy, we developed a novel structure in which a pair of electrodes was used, one on an inner and the other on an outer surface of a lamp bulb. A comparison was done with a conventional bulb. At the same inverter conditions, the new lamp could be run at only 77% of the voltage of the conventional one. Consequently, the lamp input power increased about 6%, and the illuminance increased about 7∼8%. No luminous efficacy improvement was observed.
