Patent ID: 8371701

Claim:
A discharge lamp lighting device of a projector generating a projection image by using a color wheel having even-numbered color segments rotating in an optical path of white light emitted from a discharge lamp to produce transmitted light of even-number colors in a time-divided manner and to illuminate an image display element with the transmitted light, the discharge lamp lighting device comprising: a polarity inversion signal generating unit generating a polarity inversion signal for changing a polarity of a voltage applied to the discharge lamp; and a lamp polarity changing unit changing the polarity of the voltage applied to the discharge lamp on a basis of the polarity inversion signal, wherein the polarity inversion signal generating unit generates the polarity inversion signal at a boundary between each of the even-numbered color segments, and generates an additional polarity inversion signal in a segment region corresponding to at least one specific color among the even-number colors, such that a polarity of each of the even-numbered color segments in a current rotation period is inverted in a next rotation period, wherein the additional polarity inversion signal is: a) generated at an adjustable position within at least one of the even-numbered color segments, and b) generated an odd integer number of times in each of the current rotation period and the next rotation period.