| 摘要 |
PROBLEM TO BE SOLVED: To provide a lighting device for a showcase that may suppress high cost of plural fluorescent lamps when each of those is switched on and off sporadically with different timing by adjusting frequencies of supplied power to the each lamp. SOLUTION: A lighting device for showcase applies electricity to a lamp 26 outside the case when a switch 31 for the lamp outside the case is operated on, and adjusts the frequency of the applied power and light up the lamp 26. Then, in the above situation, when a switch 42 for a lamp inside the case is operated on the device applies power to a lamp 23 inside the case and after raising the power frequency to a level where the lamp 26 is not yet put out then the device lowers the frequency little by little to preheat and to light the lamp 23. |
