Patent ID: 7745843

Claim:
A light emitting device comprising: a substrate layer; a first layer which is disposed above the substrate layer, and which comprises at least one layer including a semiconductor cladding layer of a first conductivity type; an active layer disposed above the first layer; and a second layer which is disposed above the active layer, and which comprises a semiconductor cladding layer of a second conductivity type, a current-diffusion layer, and an intermediate layer located above the current-diffusion layer, the second layer having a two-dimensional periodic structure in a surface thereof, wherein the two-dimensional periodic structure is formed above the current diffusion layer, wherein the first layer includes at least one layer having a refractive index that is lower than a refractive index of the active layer and lower than a refractive index of a layer of the second layer that is adjacent to the active layer, wherein each constituent layer of the second layer other than the intermediate layer has a lower refractive index than the active layer, and wherein the intermediate layer has a refractive index that is less than or equal to the refractive index of the active layer and that is higher than a refractive index of the semiconductor cladding layer of the second conductivity type.