DISCHARGE LAMP LIGHTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of adapting plural kinds of discharge lamps different in rated lamp electric power. SOLUTION: A lamp discriminating circuit 7 being a lamp discriminating means is provided for discriminating the kinds of discharge lamps La. The lamp discriminating circuit 7 is provided with an input current detecting means composed of a current transformer CT and a resistance R3, and a comparator CP1 for comparing end-to-end voltage VR3 of the resistance R3 with a reference voltage value determined by a DC voltage source E1. The reference voltage value is set so as to be capable of discriminating the discharge lamps La different in the rated lamp electric power. An output terminal of the lamp discriminating circuit 7 is connected to a chopper control circuit 3 via a switch SW and a latch circuit 6. The chopper control circuit 3 adjusts output voltage VDC of a chopper circuit 1a on the basis of an output signal of the comparator CP1. The chopper control circuit 3 constitutes a correcting means for correcting a lighting characteristic of the discharge lamps La according to a discriminating result of the lamp discriminating means.