Patent ID: 8469516

Claim:
An illumination apparatus comprising: a light source; a reflective light valve configured to modulate light emitted from the light source; a polarization conversion element configured to align polarization directions of the light emitted from the light source in one polarization direction; a color separation unit configured to separate the light whose polarization directions are aligned in the one polarization direction by the polarization conversion element; and a polarization adjustment element configured to adjust a polarization state of light in a predetermined wavelength band within a wavelength range of the light emitted from the light source, wherein the polarization adjustment element is provided between the polarization conversion element and the color separation unit on an optical path of the light emitted from the light source and the polarization adjustment element adjusts a ratio of a P polarization component and a S polarization component included in light having the predetermined wavelength band in accordance with applied voltage to the polarization adjustment element.