Abstract: A first illumination light source emits a first illumination light ray which is a first polarized light. Either one of an s-polarized light and a p-polarized light, which are linearly polarized light, is the first polarized light and the other is a second polarized light. A second illumination light source emits a second illumination light ray. A dichroic mirror includes a specific polarization reflection area and a transmission area. The specific polarization reflection area reflects the first polarized light and transmits the second polarized light and the second illumination light ray. The transmission area transmits the first and second illumination light rays. A phase difference plate converts linearly polarized light into circularly polarized light. A polarization conversion element transmits either the first or second polarized light, shifts an optical axis of the other, and aligns the first and second illumination light rays to the first or second polarized light.