(57) [Object] To provide a high pressure discharge lamp lighting device which can reduce
flickering of a high-pressure discharge lamp with a relatively simple control.
[Means for Settlement] Upon start of lighting of a high-pressure discharge lamp, after
the high-pressure discharge lamp reaches a substantially stable state or reaches a
predetermined lamp voltage, the high-pressure discharge lamp is lighted in at least
three lighting modes with a predetermined average power put into the high-pressure
discharge lamp, and in the lighting modes, a period of a positive polarity is nearly
equal to a period of a negative polarity in a first mode, a period of a positive polarity
is longer than a period of a negative polarity in a second mode, and a period of a
positive polarity is shorter than a period of a negative polarity in a third mode.
Lighting frequencies in the second mode and the third mode are equal to or less than
a lighting frequency in the first mode, each of periods t1, t2, t3 in the modes is
at least one cycle, at least one first mode, and at least one second mode and at least
one third mode are collectively defined as one set and the one set is repeated.
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