Arrayed waveguide grating type optical multiplexer/demultiplexer and optical waveguide circuit

An arrayed waveguide grating optical multiplexer/demultiplexer comprising:

• at least one optical input waveguide;
• a first slab waveguide connected to an output end of said at least one optical input waveguide;
• an arrayed waveguide connected to an output end of said first slab waveguide and being a plurality of channel waveguides arranged side by side, for transmitting light that has traveled through said first slab waveguide, said channel waveguides having different predetermined lengths;
• a second slab waveguide connected to an output end of said arrayed waveguide;
• at least one optical output waveguide connected to an output end of said second slab waveguide;
• and
• at least one multi-mode waveguide connected between at least one of said at least one optical input waveguide and said first slab waveguide or between said second slab waveguide and said at least one optical output waveguide, said at least one multi-mode waveguide including:
• a multi-mode waveguide configured to realize multi-mode and being a multi-mode broadening waveguide having a width which increases toward a direction of an arrayed waveguide.

An array waveguide grating optical multiplexer/demultiplexer comprising:

• input optical waveguide means for receiving an optical signal;
• first slab waveguide means connected to an output end of said optical input waveguide means;
• arrayed waveguide means connected to an output end of said first slab waveguide mean for transmitting light that has traveled through said first slab waveguide;
• second slab waveguide means connected to an output end of said arrayed waveguide means;
• output optical waveguide means connected to an output end of said second slab waveguide means;
• and
• multi-mode waveguide means at least one multi-mode waveguide connected between at least one of said at least one optical input waveguide and said first slab waveguide or between said second slab waveguide and said at least one optical output waveguide, said at least one multi-mode waveguide for realizing multi-mode and including multi-mode broadening waveguide means.

An arrayed waveguide grating optical multiplexer/demultiplexer comprising:

• at least one first optical waveguide;
• a first slab waveguide;
• an arrayed waveguide connected to said at least one first optical waveguide via said first slab waveguide, said arrayed waveguide comprising a plurality of channel waveguides each of which has a different length;
• a second slab waveguide;
• a plurality of second optical waveguides connected to said arrayed waveguide via said second slab waveguide;
• and
• at least one multi-mode waveguide having a first end portion and a second end portion, a second width of the second end portion being larger than a first width of the first end portion, the first end portion of each of said at least one multi-mode waveguide being connected to each of said at least one first optical waveguide, the second end portion of each of said at least one multi-mode waveguide being connected to said first slab waveguide, a width of said at least one multi-mode waveguide increasing from the first end portion toward the second end portion and being configured to realize multi-mode.

An arrayed waveguide grating optical multiplexer/demultiplexer comprising:

• at least one first optical waveguide;
• a first slab waveguide;
• an arrayed waveguide connected to said at least one first optical waveguide via said first slab waveguide, said arrayed waveguide comprising a plurality of channel waveguides each of which has a different length;
• a second slab waveguide;
• a plurality of second optical waveguides connected to said arrayed waveguide via said second slab waveguide;
• and
• a plurality of multi-mode waveguides each having a third end portion and a fourth end portion, a fourth width of the fourth end portion being larger than a third width of the third end portion, the third end portion of each of said plurality of multi-mode waveguides being connected to each of said plurality of second optical waveguides, the fourth end portion of each of said plurality of multi-mode waveguides being connected to said second slab waveguide, a width of said multi-mode waveguides increasing from the third end portion toward the fourth end portion and being configured to realize multi-mode.

An arrayed waveguide grating optical multiplexer/demultiplexer comprising:

• at least one first optical waveguide;
• a first slab waveguide;
• an arrayed waveguide connected to said at least one first optical waveguide via said first slab waveguide, said arrayed waveguide comprising a plurality of channel waveguides each of which has a different length;
• a second slab waveguide;
• a plurality of second optical waveguides connected to said arrayed waveguide via said second slab waveguide;
• at least one first multi-mode waveguide having a first end portion and a second end portion, a second width of the second end portion being larger than a first width of the first end portion, the first end portion of each of said at least one first multi-mode waveguide being connected to each of said at least one first optical waveguide, the second end portion of each of said at least one first multi-mode waveguide being connected to said first slab waveguide, a width of said at least one first multi-mode waveguide increasing from the first end portion toward the second end portion and being configured to realize multi-mode;
• and
• a plurality of second multi-mode waveguides each having a third end portion and a fourth end portion, a fourth width of the fourth end portion being larger than a third width of the third end portion, the third end portion of each of said plurality of second multi-mode waveguides being connected to each of said plurality of second optical waveguides, the fourth end portion of each of said plurality of second multi-mode waveguides being connected to said second slab waveguide, a width of said second multi-mode waveguides increasing from the third end portion toward the fourth end portion and being configured to realize multi-mode.

An optical waveguide circuit comprising:

• a multi-mode waveguide comprising:
• a first end portion;
• and
• a second end portion having a second width larger than a first width of the first end portion, the first end portion being configured to be connected to a first optical waveguide, the second end portion being configured to be connected to a first slab waveguide, a width of said multi-mode waveguide increasing from the first end portion toward the second end portion and being configured to realize multi-mode.