| 摘要 |
PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device wherein an energy efficiency is stabilized irrespective to a lighting condition of the discharge lamp, and the discharge lamp is stably turned on irrespective of voltage fluctuations of an alternating current power supply. SOLUTION: This is provided with a direct current power supply part 10, an inverter part INV, a light controller 20, and a feed back control part 30 wherein a frequency of on/off of switching elements Q1, Q2 of the direct current power supply part 10 is varied in accordance with a light control signal from the light controller 20. In the feed back control part 30, by varying the frequency of on/off of switching elements Q1, Q2 of the direct current power supply part 10 in accordance with the light control signal, the energy efficiency can be stabilized irrespective of the lighting condition of the discharge lamp Lp, and further in the feed back control part 30, by varying the frequency in accordance with the output power from the direct current power supply part 10, the energy efficiency can be stabilized irrespective of the lighting condition of the discharge lamp Lp. Furthermore, in the feed back control part 30, by varying the frequency in accordance with the output power from the direct current power supply part 10, the discharge lamp Lp can be turned on stably irrespective of the voltage fluctuations of the alternating current power supply Vs. |
