Wavelength-division multiplexed optical integrated circuit with vertical diffraction grating

A wave division multiplexed optical communication system comprising:

• (A) a transmitter multiplexer integrated circuit having a first semiconductor waveguide layer, comprising:
• (1) a succession of first diffraction grating points in said first waveguide layer along a first diffraction grating contour,
• (2) a diode laser array in said first waveguide layer near plural laser optical ports facing said succession of first diffraction grating points along a first direction, respective diode lasers in said array corresponding to respective ones of a predetermined succession of wavelengths,
• (3) an optical fiber having one end thereof terminated at said first waveguide layer, said one end of said optical fiber facing said succession of first diffraction grating points along a second direction,
• (4) wherein said diffraction grating points are spatially distributed along said first contour in such a manner as to diffract light of respective ones of said succession of wavelengths between said one end of said optical fiber and corresponding ones of said laser optical ports;
• (B) a receiver demultiplexer integrated circuit having a second semiconductor waveguide layer, comprising:
• (1) a succession of second diffraction grating points in said second waveguide layer along a second diffraction grating contour,
• (2) a photodetector diode array in said second waveguide layer having plural detector optical ports facing said succession of diffraction grating points along a third direction, respective photodetector diodes in said array corresponding to respective ones of said predetermined succession of wavelengths,
• (3) another end of said optical fiber being terminated at said second waveguide layer, said other end of said optical fiber facing said second succession of diffraction grating points along a fourth direction,
• (4) wherein said second diffraction grating points are spatially distributed along said second contour in such a manner as to diffract light of respective ones of said succession of wavelengths between said other end of said optical fiber and corresponding ones of said detector optical ports.

A switching node in an optical communication network, comprising:

• a plurality of outgoing optical fibers and a plurality of incoming optical fibers;
• a plurality of multiplexers formed on an integrated circuit having a waveguide layer, each of said multiplexers comprising:
• (1) a succession of first diffraction grating points in said first waveguide layer along a first diffraction grating contour,
• (2) a diode laser array in said first waveguide layer near plural laser optical ports facing said succession of first diffraction grating points along a first direction, respective diode lasers in said array corresponding to respective ones of a predetermined succession of wavelengths,
• (3) one end of a corresponding one of said outgoing optical fibers being terminated at said first waveguide layer and facing said succession of first diffraction grating points along a second direction,
• (4) wherein said diffraction grating points are spatially distributed along said first contour in such a manner as to diffract light of respective ones of said succession of wavelengths between said one end of said optical fiber and corresponding ones of said laser optical ports;
• a plurality of demultiplexers formed on an integrated circuit having a second waveguide layer, each of said demultiplexers comprising:
• (1) a succession of second diffraction grating points in said second waveguide layer along a second diffraction grating contour,
• (2) a photodetector diode array in said second waveguide layer having plural detector optical ports facing said succession of diffraction grating points along a third direction, respective photodetector diodes in said array corresponding to respective ones of said predetermined succession of wavelengths,
• (3) one end of a corresponding one of said incoming optical fibers being terminated at said second waveguide layer and facing said second succession of diffraction grating points along a fourth direction,
• (4) wherein said second diffraction grating points are spatially distributed along said second contour in such a manner as to diffract light of respective ones of said succession of wavelengths between said other end of said optical fiber and corresponding ones of said detector optical ports;
• and
• control circuitry for sensing electronic signals from said photodetector diodes and for applying electronic control signals to said lasers in response to said electronic signals from said diodes.