Polarization beam splitter and image projection apparatus

An image projection apparatus comprising:

• a polarization beam splitter that includes a substrate, and a plurality of members that extend in a first direction and are arranged in or on the substrate in a second direction orthogonal to the first direction with a predetermined period, each member having a refractive index of 2.8 or higher and an extinction coefficient of 1 or smaller for a predetermined wavelength, the polarization beam splitter providing a product with 85% or higher of a transmittance of light for the predetermined wavelength polarized in a first polarization direction perpendicular to the first direction and an incidence direction of incident light on the polarization beam splitter which forms an angle of 90° with respect to the first direction and an angle of 45° with respect to the second direction, and a reflectance of light for the predetermined wavelength polarized in a second polarization direction parallel to the first direction;
• and
• a light modulation element configured to modulate the light polarized in the first polarization direction that has transmitted through the polarization beam splitter into the light polarized in the second polarization direction, and to emit the light polarized in the second polarization direction to the polarization beam splitter.