| 摘要 |
PURPOSE:To provide a Y branch optical waveguide with less loss in a branch part and easy for manufacture. CONSTITUTION:The Y branch optical waveguide is provided with an input waveguide 20 in a clad on a substrate, a tapered waveguide 21 connected to the input waveguide 21 and whose output side width is expanded and branch waveguides 22, 23 connected to the tapered waveguide 21 without in contact with each other at fixed interval and branching an inputted beam to two parts. Then, a connection part 26 between the branch waveguides 22, 23 and the tapered waveguide 21 is expanded to a value adding twice of the width W1 of the input end side of the branch waveguides 22, 23 and the width W of the output end side of the branch waveguides 22, 23. |
