To enhance design flexibility, while having a compact optical system, for condensing positions of polarized light separated in two, in a polarizing optical element for separating incident light into two polarized lights having each different polarization state and condensing the lights.

This polarizing optical element is constituted of a birefringent material, and one surface of the polarizing optical element is curved. Hereby, a refracting power becomes different according to a polarization state of light, and each condensing position of the polarized light separated in two becomes different. Since the difference of each condensing position becomes large in proportion to reduction rate of a radius of curvature of the curved surface, design flexibility of the condensing position can be secured by designing the curved surface shape properly.