A projector can form images of illumination system on respective optical paths at positions of corresponding liquid crystal display panels with respect to a light emission surface of a cross dichroic prism without relatively inverting the images and without increasing the number of lenses from the number of lenses included in a relay optical path structure in related art. Moreover, the projector can equalize the magnification of the images formed on the respective liquid crystal display panels by controlling relative image-forming conditions of the first and second optical paths in advance. Thus, deterioration of white balance and color unevenness of light projected by the projector can be reduced even when light emission distribution of a light source varies with elapse of time, for example.