Apparatus for operating discharge lamp.

摘要

An apparatus for operating a discharge lamp variably permits a stable power supply circuit (10) to set the lamp current of a discharge lamp (40) in two or greater levels. A temperature detector (30) detects the temperature of the discharge lamp (40). When the lamp current set by the stable power supply circuit (10) is equal to or below a predetermined value and the temperature is equal to or below a predetermined level, the lower limit of the lamp current is increased. Accordingly, the discharge lamp (40) is lit through an inverter circuit (20) with the raised voltage so as to prevent lighting failure from occurring in the discharge lamp (40) due to a low lamp current at a low temperature. <IMAGE>