Patent attributes
A lighting control technology for a discharge lamp can be capable of suppressing start-up variations of luminous flux in consideration of variations in lamp voltage. A discharge lamp lighting apparatus can include a lamp voltage detection circuit and a lamp current detection circuit for detecting a lamp voltage and a lamp current of a discharge lamp, respectively. The lamp can include a control circuit for performing a starting-time control for applying a current or power several times as high as a rated value of the lamp in order to light the discharge lamp substantially instantaneously, and a stable-time control for lighting the discharge lamp stably at substantially constant rated power. The lamp current or lamp power can be controlled from a starting time to a stable time in accordance with the voltage value detected by the lamp voltage detection circuit. The starting-time control can be switched to the stable-time control depending on an increase in the voltage value detected by the lamp voltage detection circuit from the starting time to the stable time and depending on a lapse of an arbitrary time.
