| 摘要 |
[Object] To provide a low pressure discharge lamp lighting device which can stably performs dimmed lighting of the lamp to a lower luminous flux level as compared to a control to make a lamp current or a lamp power constant. [Means for Settlement] In a low pressure discharge lamp lighting device including an inverter circuit 4 including one or more switching elements Q1, Q2 for switching a DC voltage outputted from a DC voltage source Vdc, a driving circuit 8 for turning on/off the switching elements Q1, Q2 with a high frequency and a resonance circuit to which a voltage switched by the switching elements Q1, Q2 is applied and supplies a resonance voltage to a discharge lamp LA, wherein feedback means 5 adapted to adjust the DC voltage outputted from the DC voltage source Vdc or turning-on/off of the switching elements Q1, Q2 so that an output of the calculating means 10 which is obtained by dividing the voltage V1a of the discharge lamp LA detected by the lamp voltage detecting means 11 by a current I1a of the discharge lamp detected by the lamp current detecting means 13 becomes substantially equal to a reference voltage Vdim is provided.
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