LIGHTING DEVICE OF DISCHARGE LAMP

摘要

PROBLEM TO BE SOLVED: To provide a lighting device of a discharge lamp that can stably make a rated lighting by using an inverter means capable of changing the starting frequency and the duty ratio. SOLUTION: First, the lamp voltage is detected by the direct current voltage detecting circuit 13, and based on that signal, the switching regulator control IC 19 is controlled through the comparison circuit 24 and the constant current circuit 26 and the starting frequency of the inverter circuit is controlled, so that the reference signal adding the output signals of the lamp current processing circuit 21 and the bias circuit 22 may coincide with the output signal of the direct current detecting circuit 23 corresponding to the input current from the inverter circuit to the discharge lamp.