Patent ID: 7977682

Claim:
A light emitting device having a first-conduction-type cladding layer, an active layer structure, and a second-conduction-type cladding layer, each of which comprises a III-V compound semiconductor, wherein said active layer structure is located between said first-conduction-type cladding layer and said second-conduction-type cladding layer, said light emitting device comprising: a first-conduction-type-side electrode configured to inject carriers into said first-conduction-type cladding layer; and a second-conduction-type-side electrode configured to inject carriers into said second-conduction-type cladding layer, wherein said first-conduction-type-side electrode has an opening, and said second-conduction-type-side electrode has a main-electrode-portion partially surrounded by said first-conduction-type-side electrode, and an extracting portion configured to extract said main-electrode-portion outside said first-conduction-type-side electrode through the opening, and said main-electrode-portion is a part of a curve of constant width or a constant-width figure, and an interval between an outer edge of said main-electrode-portion and an inner edge of said first-conduction-type-side electrode is substantially constant, wherein the curve of constant width or the constant-width figure comprises a Reuleaux polygon or Reuleaux triangle.