Wavelength-selective polarization conversion element for generating two light components having polarization directions and wavelength regions different from each other, illumination optical system, and image projection apparatus including the element

摘要

The wavelength-selective polarization conversion element includes a plurality of polarization splitting surfaces each of which separates entering light into two polarized light components having polarization directions different from each other, a plurality of phase plates that causes a polarization direction of one polarized light component in the two polarized light components from the polarization splitting surfaces to coincide with a polarization direction of the other polarized light component. The element further includes a plurality of dichroic surfaces that is disposed closer to a light entrance side than the plurality of polarization splitting surfaces or between the plurality of polarization splitting surfaces and the plurality of phase plates, each dichroic surface separating entering light into two wavelength region components different from each other. The element is capable of generating light components having different polarization directions and different wavelength regions from non-polarized light while preventing a reduction of light use efficiency.