| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp lighting device capable of balancing flicker prevention, with the maintenance of the distance among lamp electrodes, and moreover, is low in noise and loss. <P>SOLUTION: This high-pressure discharge lamp lighting device comprises an A.C. power supply circuit applying an alternating lamp current to a high-voltage discharge lamp; a control circuit controlling the A.C. power supply circuit; the control circuit can cause the A.C. power supply circuit to output a reference waveform current that is a rectangular-wave current of 50 Hz to 1 kHz as the alternating lamp current; and a flicker preventing waveform current, formed by deforming the reference waveform current. In the high-pressure discharge lamp lighting device, the control circuit is provided with a change-over means for changing over the alternating lamp current, from the flicker preventing waveform current to the reference waveform current with a predetermined timing; and a determination means for monitoring a parameter related to a lighting state of the high-pressure discharge lamp, to determine the predetermined timing based on the parameter. <P>COPYRIGHT: (C)2008,JPO&INPIT |
