DISCHARGE LAMP LIGHTING DEVICE, ILLUMINATION DEVICE, AND ILLUMINATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device which can light up a discharge lamp stably even if a light dimming ratio is small and which has a simple composition.

SOLUTION: The discharge lamp lighting device 100 is provided with an inverter circuit 300 to light on a discharge lamp 11, a discharge lamp state detecting circuit 320 to detect and output a discharge lamp variation signal which shows a variation of a voltage of the discharge lamp 11 and a micro-computer 312 which inputs the discharge lamp variation signal and detects a variation width of the inputted discharge lamp variation signal and starts frequency control of an oscillation frequency of the inverter circuit 300 when a variation width of the detected variation signal exceeds a predetermined set value and continues the frequency control of the inverter circuit 300 till the variation width of the variation signal corresponding to the frequency control comes below the set value.

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