OPTICAL WAVEGUIDE CIRCUIT

摘要

PROBLEM TO BE SOLVED: To suppress the dissipation of light signals at branch points and to lessen the propagation loss of light by constituting branch type optical waveguides and disposing plural adjacent non-parallel waveguides and the specific embedment layers arranged between the respective adjacent waveguides. SOLUTION: This optical waveguide circuit has the embedment layers 120 composed of the same material as the material of cores 103a in the regions between the adjacent cores 103a of the array waveguide 103 from an input side slab waveguide 102. The embedment layers 120 are formed by being held by a lower clad layer 106 and an upper clad layer 107 in the regions held by the adjacent cores 103a. The embedment layers 120 are so formed that the height is lower the more distant from the slab waveguide 102. The embedment layers 120 are so formed that thickness is thinner more distant from the connection point with the input side slab waveguide 102. The refractive index range of the material of the embedment layers 120 satisfies nc