Patent ID: 6424760
Filing Date: 2002-07-23
Classification: G02B

Abstract:
An optical multiplexer/demultiplexer comprising:a substrate; first and second slab waveguides, each having a predetermined slab length, disposed on said substrate; at least one input waveguide, disposed on said substrate, having an optical output end optically connected to an optical input end face of said first slab waveguide; a plurality of output waveguides two-dimensionally arranged on said substrate while in a state where respective optical input ends thereof are optically connected to an optical output end face of said second slab waveguide, said output waveguides being provided so as to correspond to respective signals having channel wavelengths set as signal channels at a predetermined wavelength interval; and a plurality of channel waveguides two-dimensionally arranged on said substrate while in a state where an optical input end of each channel waveguide is optically connected to an optical output end face of said first slab waveguide so as to sandwich said first slab waveguide together with said input waveguide whereas an optical output end of each channel waveguide is optically connected to an optical input end face of said second slab waveguide so as to sandwich said second slab waveguide together with said output waveguides, said channel waveguides having respective lengths different from each other; wherein each of said channel waveguides is arranged on said substrate while in a state where a space between said optical output end face of said first slab waveguide and said optical input end of said channel waveguide is at least three times a width or thickness of each of said channel waveguides so as to ameliorate deterioration in a crosstalk characteristic between adjacent signal channels caused upon separating said channel waveguide and said first slab waveguide from each other.