| 摘要 |
PROBLEM TO BE SOLVED: To form two-way waveguides and reflection end faces in one etching process by anisotropic etching operation by providing the axes of the two-way waveguides to be parallel with each other at least in the waveguide part on the side of the reflection end face and the reflection end faces to be parallel with each other. SOLUTION: A two-way waveguide array 26 is arranged so that the optical axes 01-05 of a back and forth waveguides 28 become parallel with each other. Reflection end faces 33 are provided to be parallel with each other. A planar waveguide part 14 guides a light beam from an input/output waveguide 24 to the two-way waveguide array 26, reflection light beams from the two-way waveguides 28 are again guide and the focused light beam is demultiplexed to the input/output waveguide 24. An input/output waveguide array 20 is provided with an input/output port 22 on the side of end face of a substrate 12 and makes a frequency multiplexed light beam incident on the input/output waveguide 24. The two-way waveguide array 26 is provided with the two-way waveguides 28 having different lengths for guiding the light beam incident from the planar waveguide part 14 and the reflection end faces 33 for reflecting the light beam. |
