| 摘要 |
PROBLEM TO BE SOLVED: To provide an electrodeless discharge lamp lighting device to prevent the occurrence of flickering and instability of an electrodeless discharge lamp at frequency switching time. SOLUTION: A control circuit 6 gradually changes an output frequency from a variable frequency oscillation circuit OSC2 until an electrodeless discharge lamp 1 is lighted, and changed the output frequency this time in the inverse direction of time up to lighting when the electrodeless discharge lamp 1 is lighted, and returns the frequency up to a reference frequency (f) or its vicinity. Afterwards, a switch S is switched, and a signal of a contact frequency from a fixed frequency oscillation circuit OSC1 is imparted to the gates of switching element Q1 and Q2 of an amplifier circuit 5 through a transformer T, and lighting of the electrodeless discharge lamp 1 is maintained. |
