Optical device with an optical coupler for effecting light branching/combining by splitting wavefront of light

摘要

The optical device includes a channel or three-dimensional light waveguide for propagating a light wave therethrough and an optical coupler for effecting at least one of branching and combining of the light wave by splitting a wavefront of a field distribution of the light wave. The coupler is produced by forming a portion (10) whose reflection factor is different from the waveguide, extending in a vertical direction of the waveguide. The portion of different reflection factor (10) is formed deep enough in the vertical direction to perform the splitting of the wavefront of the field distribution of the light wave with respect to at least a horizontal or lateral direction, or the portion of different reflection factor is formed at a flat portion of the waveguide.