| 摘要 |
<p>A discharge lamp operation apparatus includes a DC power supply circuit (10), a voltage conversion circuit (11), an inverter circuit (13), a load circuit (15), a control unit (1), and a pulse voltage superimposing unit (3). The pulse voltage superimposing unit (3) controls switching elements (Q3, Q4) so as to superimpose a pulse voltage over the applied voltage at both ends of the discharge lamp (LA). The period of time until the discharge lamp (LA) is lit is divided into a preheat period for preheating the discharge lamp and a start period for starting the discharge lamp. During the start period, output voltage (Vdc) of the voltage conversion circuit (11) is gradually increased by the control unit (1) and a pulse voltage is superimposed over the applied voltage at the both ends of the discharge lamp (LA) by the pulse voltage superimposing unit (3).</p> |
