Optical switching device
AssigneeFujitsu Limited
InventorManabu Matsuda
Life of this patent
Estimating the term…
Abstract
An optical switching device includes a transparent optical waveguide, a plurality of light emitting elements provided on the optical waveguide for producing wavelength-multiplex optical signals, a plurality of diffraction gratings provided on the optical waveguide in correspondence to the light emitting elements for causing a diffraction of the wavelength-multiplex optical signals supplied thereto, and a plurality of photodetection elements provided on the optical waveguide in correspondence to the paths of the optical beams diffracted by the diffraction gratings, wherein the pitch of the diffraction gratings is optimized with respect to the position of the photodetection elements such that optical signal components having the same wavelength reach the same photodetection elements from the plurality of diffraction gratings.
Claims15
An optical switching device having a plurality of input ports for receiving a plurality of wavelength-multiplex optical signals, said optical switching device separating each of said plurality of wavelength-multiplex optical signals into a plurality of optical signal components each having a wavelength corresponding to a channel of the wavelength-multiplex signals, such that each of said plurality of optical signal components is directed to a corresponding one of a plurality of output ports provided in correspondence to the wavelengths of the optical signal components forming said wavelength-multiplex signals, said optical switching device comprising:
- an optical waveguide formed of an optically transparent medium;
- a plurality of light emitting elements provided on said optical waveguide as said plurality of input ports, each of said light emitting elements producing a wavelength multiplex optical signal that includes therein a plurality of optical signal components having respective, mutually different wavelengths and injecting said wavelength-multiplex optical signal into said optical waveguide along a ray path that is pertinent to said wavelength-multiplex optical signal;
- a plurality of photodetection elements provided on said optical waveguide at respective positions that are offset from said plurality of light emitting elements as said output ports, said positions of said photodetection elements corresponding to the wavelengths of said optical signal components forming said wavelength-multiplex optical signals, each of said photodetection elements detecting a signal component that propagates through said optical waveguide and has a wavelength corresponding to the position of said photodetection element;
- and
- a plurality of diffraction gratings each provided on said optical waveguide in correspondence to a ray path of a light emitting element included in said plurality of light emitting elements, for separating a wavelength-multiplex signal incident thereto along said ray path, into a plurality of optical signal components constituting said wavelength-multiplex signal, said diffraction grating causing a diffraction of said plurality of optical signal components thus separated to respective, corresponding photodetection elements that are included in said plurality of photodetection elements;
- wherein each of said plurality of diffraction gratings has a position on said optical waveguide and a grating pitch, such that said position and grating pitch are different from those of other diffraction gratings.
Dependencies are inferred from the claim text.