| 摘要 |
The high-pressure discharge lamp lighting device and a high-pressure discharge lamp apparatus using this of the present invention are able to suppress the excessive drop in the lamp voltage in a high-pressure discharge lamp. The frequency of the alternating current to be supplied to the high-pressure discharge lamp 4 is switched among a first frequency, a second frequency greater than the first frequency, and a third frequency smaller than or equal to the first frequency. In the switching, a time period A, in which the alternating current of the third frequency is supplied, occurs at beginning of each of predetermined time intervals. Further, a remainder of each of the predetermined time intervals includes a time period B, in which the alternating current of the first frequency is supplied, and a time period C, in which the alternating current of the second frequency, the time period B and the time period C being alternately repeated, so as to control the time period A to be longer than the time period B and to have a length corresponding to a predetermined number of cycles, ranging from 5.5 to 50 cycles inclusive.
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