| 摘要 |
PURPOSE:To reduce crosstalk by arranging a reflector on a specific diagonal of the crossing area of a main waveguide part and branch waveguide parts. CONSTITUTION:A branch waveguide part 12 crosses the main waveguide part 11 and the crossing area 13 of those main waveguide part 11 and branch waveguide part 12 form a parallelogram optical branching device. The reflector composed of an interference film filter 14 is arranged on a short diagonal of the parallelogram crossing area 13. Consequently, when light beams L1 and L2 having some wavelength are reflected from the branch waveguide 12 to the main waveguide part 11, both beams L1 and L2 are reflected to pass through specific optical paths, so that there is no crosstalk generated. |
