DISCHARGE LAMP LIGHTING DEVICE, ILLUMINATING DEVICE, PROJECTOR

摘要

A chopper circuit (1) can control an output power using a dc power supply (E) as a power supply, with a smoothing capacitor (C1) connected between output ends of the chopper circuit (1). A polarity reversing circuit (2) applies an ac voltage to a high-pressure discharge lamp (La) using the ends voltage of the smoothing capacitor (C1) as a power supply. An output voltage from the chopper circuit (1) and a reversing frequency of the polarity reversing circuit (2) are controlled by a control circuit (4) based on the terminal voltage of the capacitor (C1) detected by a voltage detection circuit (3). The control circuit (4), with a change-over voltage set for limiting the range of a voltage detected by the voltage detection circuit (3), changes a reversing frequency in plurality of stages according to a magnitude relation between a detected voltage and a change-over voltage. A reversing frequency corresponding to a power input to a high-pressure discharge lamp is set for respective ranges of a lamp voltage to thereby prevent an arc jump from occurring.