Patent ID: 7684460

Claim:
A surface emitting laser device comprising: an active layer; a photonic crystal layer, which has a two-dimensionally periodic refractive index structure, and which is disposed adjacent to the active layer; an electrode disposed on the photonic crystal layer; and a light emitting region for emitting light, wherein the photonic crystal layer includes: a first photonic crystal region disposed under the electrode, and having a periodic refractive index structure for resonance of light within a plane, and a second photonic crystal region disposed under the light emitting region, and having a periodic refractive index structure for emitting light in a direction perpendicular to the plane, wherein the photonic crystal has a structure wherein cylindrical holes are arranged in a square grating in a medium, wherein a lattice constant of the first photonic crystal region is about (½) 1/2 times as large as a lattice constant of the second photonic crystal region, and wherein a crystal orientation of the first photonic crystal region is at an angle of 45° to a crystal orientation of the second photonic crystal region.