Patent ID: 7990075

Claim:
A high intensity discharge lamp lighting device, comprising: storage means in which a plurality of output power characteristics as data tables of lamp voltage-lamp power are stored for a rating lamp voltage range of a high intensity discharge lamp and a lamp voltage range lower than the rating lamp voltage range; minimum lamp voltage detecting means for allowing predetermined power to be outputted in an event of starting the high intensity discharge lamp, and detecting a minimum lamp voltage after the high intensity discharge lamp shifts to an arc discharge or a value equivalent to the minimum lamp voltage during a predetermined period including the minimum lamp voltage; selection means for determining which voltage range among a plurality of preset voltage ranges the minimum lamp voltage detected by the minimum lamp voltage detecting means or the value equivalent to the minimum lamp voltage, the value being detected thereby, enters, and for selecting the data table corresponding to the voltage range; and control means for controlling power supplied to the high intensity discharge lamp with reference to the data table selected by the selection means.