LOW PRESSURE MERCURY VAPOR DISCHARGE LAMP UNIT

摘要

PURPOSE:To improve the efficiency of a discharge lamp and a lighting equipment by providing a predetermined rest period for the voltage applied across electrodes when lighting the discharge lamp and by constituting so that the mole percentage is set at a predetermined value when the discharge lamp is lighted in the windless atmosphere. CONSTITUTION:A rest period of 0.5X10<-6>sec or larger and 15X10<-6>sec or less is provided for the voltage applied across electrodes 4a, 4a when lighting a low pressure mercury vapor discharge lamp 4. The discharge lamp 4 and a lighting equipment A are constituted so that the mole percentage X/Y between a mixed rare gas and the mercury vapor is set at 0.5X10<2> or above and 1.0X10<4> or below when said discharge lamp 4 is lighted at a high frequency of 1KHz or above in the windless atmosphere at 25 deg.C, thereby the efficiency of the discharge lamp 4 and also the efficiency of the whole unit can be improved.