| 摘要 |
PURPOSE: To stabilize the discharge inside a lamp after igniting a discharge lamp by continuing conductive condition and non-conductive condition of each switching element at least one time during an interval between the non- conductive condition of other switching elements. CONSTITUTION: A first diving circuit I and a second driving circuit II generate the first and second driving signals. A discharge lamp operating circuit is operated in a different condition by these driving signal, and these condition are alternately switched by the frequency of the first driving signal. At the time of the first operating condition, switching elements S2 , S3 are in non-conductive condition. A switching element S4 is in conductive condition by the first driving signal, but an element 2 is alternately switched for conductive and non- conductive by the second driving signal. When voltage of the lamp is stabilized after running a lamp La, a circuit is switched to the steady state. In the steady state, the second driving signal is not generated, and the first driving signal operates the elements S1 -S4 so as to operate a DC-AC converter. |
