Patent ID: 8923358

Claim:
A two-dimensional photonic crystal surface emitting laser light source, including: a two-dimensional photonic crystal consisting of: a plate-shaped body; and a plurality of identically-shaped and separately distributed modified refractive index areas periodically arranged in a square lattice pattern or in a rectangular lattice pattern each of the plurality of modified refractive index areas being composed of one or more identically-shaped elements having a refractive index different from that of the body; and an active layer provided on one side of the two-dimensional photonic crystal, wherein: for each of the plurality of modified refractive index areas, the one or more elements are not present at a gravity center thereof and on a first half-line extending from the gravity center in a direction within a plane of the two-dimensional photonic crystal, while the one or more elements are present at least on a portion of a second half-line extending from the gravity center in a direction opposite to the first half-line.