HIGH-PRESSURE DISCHARGE LAMP LIGHTING DEVICE AND LIGHTING FIXTURE USING THE SAME

摘要

A lighting apparatus comprises a power converting circuit (3) that includ es a plurality of switching elements (Q2-Q6) and an inductance element (L2) and that power converts an input from a DC power supply (2) and then supplie s it as a rectangular wave output to a high voltage discharge lamp (DL); and a control circuit (9) that controls the switching elements (Q2-Q6) of the p ower converting circuit (3). The control circuit (9) has a first lighting co ntrol for controlling the switching element (Q2) of the power converting cir cuit (3) to flow a current up to a predetermined peak value for each switchi ng period; and a second lighting control for supplying a desired power durin g a stable lighting of the high voltage discharge lamp (DL). The control cir cuit (9) switches between the first and second lighting controls in accordan ce with a lighting state of the high voltage discharge lamp (DL).