| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp lighting device excelling in stability as measures against unstable lighting, and mainly against a lighting failure of a discharge lamp occurring from a starting process of the discharge lamp to the life end stage thereof. SOLUTION: This lighting device comprises: a power conversion circuit 3 having a plurality of switching elements Q2-Q6 and an inductance element L2, and subjecting input from a D.C. power source 2 to power conversion to supply it to the high-pressure discharge lamp DL as rectangular-wave A.C. output; and a control circuit 9 controlling the switching elements Q2-Q6 of the power conversion circuit 3. The control circuit 9 has first lighting control controlling the switching element Q2 of the power conversion circuit 3 to carry a current until a peak value determined for every switching cycle, and second lighting control supplying desired power in stably lighting the high-pressure discharge lamp DL, and changes over the first and second lighting control in response to the lighting state of the high-pressure discharge lamp DL. COPYRIGHT: (C)2008,JPO&INPIT |
