| 摘要 |
PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp lighting device using a low frequency rectangular wave lighting method, in which temperature and light volume of a lamp rise quickly at the beginning of lighting. SOLUTION: A full bridge circuit 3 supplies the lamp current to the high pressure discharge lamp 5 using the low frequency rectangular wave lighting method, and switches the direction of the lamp current which flows the high pressure discharge lamp. A controller 8 controls the full bridge circuit 3, wherein the controller 8 controls the full bridge circuit 3 to switch the direction of the current flow in a first cycle during a warm up period after breakdown of the high pressure discharge lamp 5, and controls the full bridge circuit 3 to switch the direction of the lamp circuit in a second cycle shorter than the first cycle, during a supply power reduction control period or a rated power control period. COPYRIGHT: (C)2006,JPO&NCIPI |
