Y-BRANCH OPTICAL WAVEGUIDE AND METHOD OF DESIGNING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a Y-branch optical waveguide that has a non-equal branching ratio lower than 9 to 1, reduces an excessive loss, and improves an yield.;SOLUTION: The Y-branch optical waveguide 10 includes an input optical waveguide 12, a tapered optical waveguide 14 that is formed so that a core width extends gradually and where a narrow-side end 14a is connected to the input optical waveguide 12, and a first S-shaped curved optical waveguide 20 and a second S-shaped curved optical waveguide 22 arranged and connected to a wide-side end 14b of the tapered optical waveguide 14 via a gap 28 of a predetermined width. In the connecting section between the tapered optical waveguide 14 and the first S-shaped curved optical waveguide 20 and the second S-shaped curved optical waveguide 22, the core width of the first S-shaped curved optical waveguide 20 and the core width of the second S-shaped curved optical waveguide 22 are set equal to each other. The extending angle of a first side wall 14c of the core of the tapered optical waveguide 14 is formed to be 0°, and the extending angle of the second side wall 14d is formed to be an angle larger than 0°.;COPYRIGHT: (C)2010,JPO&INPIT