| 摘要 |
PROBLEM TO BE SOLVED: To carry out adjustment and control of the central wavelength of an array waveguide diffraction grating-type multiplexing-branching filter by a comparatively simple method. SOLUTION: The array waveguide diffraction grating-type multiplexing- branching filter comprises a channel waveguide 12 for input, an input-side slab waveguide 13, an array waveguide 14 comprising channel waveguides, an output- side slab waveguide 15 and a channel waveguide 16 for output on a substrate 11. In addition, a flat optical medium 17, which is different in refractive index from the slab waveguide core, is inserted into at least either the input-side slab waveguide or the output-side slab waveguide with an inclination against the axis vertical to the optical axis. |
