| 摘要 |
PROBLEM TO BE SOLVED: To provide a high voltage discharge lamp lighting device capable of adjusting light down to a lower light bundle level than the lowest limit of light control obtained by a conventional constant current control. SOLUTION: This device includes an electric power conversion means to carry out the total lighting or a controlled lighting by supplying an alternate current electric power to the high pressure discharge lamp of a load side by a direct current power supply as an input power supply, and in a region in which both end voltages of the electric power changing means become large as the light control becomes deeper, an output characteristic of the electric power conversion means is made to have the characteristic of increasing the output electric current of the electric power conversion means against increase of the output voltage of the electric power conversion means. The ratio of the increase of the output electric current against the increase of the output voltage is made to be nearly constant, or as the light control becomes deeper, the ratio of the increase of the output electric current is made to be larger against the increase of the output voltage. COPYRIGHT: (C)2006,JPO&NCIPI |
