Tunable optical wavelength demultiplexer

A tunable optical wavelength demultiplexer device, comprising:

• a planar waveguide;
• a plurality of cascading demultiplexer units formed in the planar waveguide, said every demultiplexer unit comprising a plurality of input waveguide channels, a plurality of output waveguide channels and a Bragg grating, every input waveguide channel angularly merging at a different acute angle with a normal of the Bragg grating, and every output waveguide channel being a mirror image of every input waveguide channel;
• a plurality of couplers, each coupler coupling to all the output waveguide channels of a corresponding demultiplexer unit;
• an input port for emitting input light, which light transmits to a input waveguide channel of the first demultiplexer unit;
• a plurality of output ports which respectively couple with a corresponding coupler, and respectively receive light from an output waveguide channel of a corresponding demultiplexer unit;
• and
• an adjustable mechanism for adjusting coupling of the input port with an input waveguide channel of the first demultiplexer unit;
• wherein, the Bragg grating of every demultiplexer unit has a different period, and each input waveguide channel of every demultiplexer unit can receive light from the previous demultiplexer unit.

A tunable optical wavelength demultiplexer device, comprising:

• a planar waveguide;
• a plurality of cascading demultiplexer units formed in the planar waveguide, said every demultiplexer unit comprising a plurality of input waveguide channels, a plurality of output waveguide channels and a Bragg grating, every input waveguide channel angularly merging at a different acute angle with a normal of the Bragg grating, and every output waveguide channel being a mirror image of every input waveguide channel;
• a plurality of couplers, each coupler coupling to all the output waveguide channels of a corresponding demultiplexer unit;
• an input port for emitting input light, which light transmits to a input waveguide channel of the first demultiplexer unit;
• a plurality of output ports which respectively couple with a corresponding coupler, and respectively receive light from a output waveguide channel of a corresponding demultiplexer unit;
• and
• an adjustable mechanism for adjusting coupling of the input port with an input waveguide channel of the first demultiplexer unit;
• wherein, the Bragg grating of every demultiplexer unit has a different period, and is parallel to the other Bragg gratings of the demultiplexer device, and corresponding input waveguide channels of every demultiplexer unit are parallel to each other and receive light from the last demultiplexer unit.