| 摘要 |
PROBLEM TO BE SOLVED: To provide a grating capable of obtaining almost completely flat wavelength loss characteristics in a passing band without increasing the wavelength loss of propagated light. SOLUTION: This grating is constituted of an input channel waveguide 1, an output channel waveguide 2 provided with plural waveguides 2A-2H, a channel waveguide array 3 constituted of the plural waveguides successively made longer by a prescribed waveguide length difference and a first slab waveguide 4A and a second slab waveguide 4B provided with a sectorial shape. In this case, the channel waveguide array 3 is arranged so as to connect the first slab waveguide 4A and the second slab waveguide 4B. Also, the second slab waveguide 4B is provided with a reflector 5 and the reflector 5 is formed on a side face opposing the channel waveguide array 3 inside the second slab waveguide 4B. |
