| 摘要 |
PROBLEM TO BE SOLVED: To provide an array waveguide diffraction grating type optical multiplexer/demultiplxer, having large 1 dB band width, is low in ripples and can suppress the deterioration in adjacent crosstalks. SOLUTION: A waveguide forming section 10, constituted by successively forming light input waveguides 12, a first slab waveguide 13, a slab waveguide 14 provided with plural channel waveguides 14a varying in their each other's lengths from each other by a set quantity, a second slab waveguide 15 and a plurality of light output waveguides 16 disposed juxtaposedly is formed on a substrate 11. The exit side of at least 1 or more pieces of the light input waveguides 12 is provided with linear waveguides 1 of the width narrower than the width of the light input waveguides 12, and the exit side thereof is provided with trapezoidal waveguides 5 of the width expanding toward the array waveguide 14 side. The upper bases 4 of the trapezoidal waveguides 5 are made larger in width than the width of the light input waveguides 12. |
