Patent ID: 8363314

Claim:
An SLD (superluminescent diode) comprising: a substrate; an optical waveguide comprising a lower clad layer, an active layer dependent on the polarization of light, and an upper clad layer sequentially stacked on the substrate, the optical waveguide comprising linear, curved, and tapered waveguide areas, the tapered waveguide area including the active layer or a tapered waveguide; and first current blocking layers and second current blocking layers formed around the optical waveguide to block a flow of current out of the active layer, wherein the first current blocking layers are positioned at left and right sides of at least one of the tapered waveguide and the active layer of the tapered waveguide area, forming a first BH (buried hetero) structure, and wherein the second current blocking layers are positioned at leftmost and rightmost sides of the first current blocking layers, forming a second BH structure.