US 6,665,467 B2 · Optical wavelength filter

Abstract

An optical wavelength filter having an optical coupler, for suppressing the generation of a double peak caused by a difference of propagation constants between intrinsic modes of light in an optical coupler. The optical wavelength filter includes first and second optical couplers for exciting multiple modes of light in each wavelength of WDM light and providing a phase difference of p/2 between different modes of multiple modes of light, and a mode converter provided between the first and second optical couplers. The mode converter performs mode conversion between the modes of light belonging to a specific wavelength, whereby the phase difference of each mode of light constituting the light of a specific wavelength, and the phase difference between the modes of light constituting the light of another wavelength, are independently adjusted so as to output light of a specific wavelength and light of another wavelength from separate output ports.

Claims12

Dependent claims

An optical wavelength filter, comprising:

first and second optical couplers for propagating wavelength division multiplexing (WDM) light comprising a plurality of wavelengths, exciting multiple modes of light comprising high-order modes of light for light of each wavelength of said WDM light, and providing a predetermined phase difference between different modes of light of said multiple modes of light;
and
a mode converter, which is arranged between said first and second optical couplers, and which performs mode conversion between different-order modes of light belonging to a selected specific wavelength of light from among said multiple modes of light excited by said optical couplers,
wherein said mode converter comprises a multimode waveguide, and a plurality of rows of diffraction gratings which are arranged in said multimode waveguide so as to form a periodic structure along in optical wave guiding direction in said multimode waveguide, the rows of diffraction gratings extending in parallel with respect to each other while being mutually staggered by a half period.

1 more element

An optical wavelength filter, comprising:

first and second optical couplers for propagating wavelength division multiplexing (WDM) light comprising a plurality of wavelengths, exciting multiple modes of light comprising high-order modes of light for light of each wavelength of said WDM light, and providing a predetermined phase difference between different modes of light of said multiple modes of light;
and
a mode converter, which is arranged between said first and second optical couplers, and which performs mode conversion between different-order modes of light belonging to a selected specific wavelength of light from among said multiple modes of light excited by said optical couplers,
wherein said mode converter comprises a plurality of single-mode waveguides arranged in parallel, and a plurality of rows of diffraction gratings which are respectively arranged in the single-mode waveguides so as to form a periodic structure along an optical wave guiding direction in the single-mode waveguides, and so as to be mutually shifted by a half period from one another.

1 more element

Dependencies are inferred from the claim text.

Optical wavelength filter

Life of this patent

Optical wavelength filter

Life of this patent

Abstract

Claims12