An excitation light source is configured to emit excitation light. A fluorescent substance plate is configured to be excited by the excitation light and to emit fluorescent substance light having a wavelength different from a wavelength of the excitation light. A condensing optical system is configured to condense the excitation light emitted from the excitation light source to an excitation light irradiation region that is smaller than the fluorescent substance plate, to apply the excitation light to the fluorescent substance plate, and to take in fluorescent substance emission light from the excitation light irradiation region. The excitation light is applied to the fluorescent substance plate such that the excitation light irradiation region is eccentric to the fluorescent substance plate.