Patent ID: 7755718
Filing Date: 2010-07-13
Classification: G02B,G02F

Abstract:
1. An optical element having a function of splitting incident light into polarized beams, the optical element comprising: a substrate transparent for the incident light; a diffractive structure that includes a plurality of concave portions and a plurality of convex portions alternately arranged with each other, each of the plurality of concave portions and convex portions having a rectangular sectional shape, and that is provided on a first surface of the substrate; and a grid that includes a plurality of fine lines extending in a single direction and that is provided along a top surface of the diffractive structure on the first surface of the substrate, wherein conditions: d<λ and λ/n<δ≦λ are satisfied when λ represents a wavelength of the incident light; d represents a mutual distance between the fine lines; δ represents a distance between the neighboring convex portions; and n represents a refractive index of a material forming the substrate.