| 摘要 |
PROBLEM TO BE SOLVED: To provide a small sized, low cost optical wavelength multiplexer/ branching filter that small in optical loss. SOLUTION: By enlarging the difference of the specific refractive indexΔc1 between a core 8 and a clad 9 constituting the waveguides 3 to 7 is made larger and increasing the confinedness of light in waveguides 3 to 7, an optical circuit can be made smaller. In addition, if the optical circuit is miniaturized to be multi-channel circuit, since the waveguide arrangement in the connecting part with optical fibers comes to affect greatly on the element size, miniaturization can be attained by multiplexing/branching the wavelength using a pitch conversion waveguide 12. |
