An image projector has a light source emitting blue, green, and red illumination light, a digital micromirror device forming blue, green, and red images, and a projection system enlarging the images, and fulfills the formula FP≦1/(2·sin {sin−1[1/(2·FI)]+Δ}), where, when mirror surfaces forming pixels are referred to as pixel surfaces, mirror-reflected light on the pixel surface along the illumination axis is referred to as mirror-reflected light, and angles between, of the diffracted light produced as a result of the rays along the illumination axis being diffracted, the part traveling in a direction closest to the mirror-reflected light and the normal line to the image display surface is defined as diffraction angles βB, βG, and βR, then Δ represents the largest of the angles βB, βG, and βR, FI represents f-number of illumination light, and FP represents f-number of projection system.