| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of enhancing accuracy of abnormality detection. SOLUTION: The discharge lamp lighting device is constituted of a high frequency power source 3 for converting an AC power source Vac into high frequency power; a load circuit to be connected between output terminals of the high frequency power source 3; and a detecting circuit for detecting an abnormal state of a discharge lamp. The load circuit is constituted with a series circuit of a capacitor C1 for coupling; a discharge lamp La; and primary winding of a resonance choke 4, and a capacitor C2 for resonance and preheating, connected between terminals on the non-power source side of the discharge lamp La, and a resonance circuit is constituted with the resonance choke 4 and the capacitor C2. The detecting circuit is constituted with a first detecting part 5a; a second detecting part 6a; and a signal synthetic circuit 7 for forming or output by inputting the detecting output (point a) of the first detecting part 5a and the detecting output (point b) of the second detecting part 6a. When the output of the signal synthetic circuit 7 becomes abnormal, output supply to the discharge lamp is reduced. |
