Patent ID: 6941039

Claim:
A device for selecting the coupling between the modes in a waveguide, the device comprising: a housing having opposed ends with a generally hollow interior extending there between, said opposed ends each having an opening formed there through for receiving an optical fiber; an optical fiber having opposed end regions received by said openings of said housing and extending therebetween, said optical fiber defining a centerline and having a cladding surrounding a core, said core having a predetermined refractive index distribution, and said cladding having a refractive index generally less than said refractive index of said core; a grating region having a plurality of grating elements disposed in said optical fiber between said first end region and said second end region, wherein said grating region includes at least one grating element that has an azimuthally spatially varying index of refraction; and a flexure means for positioning said grating region of said optical fiber in a given position, said flexure means disposed in said interior of said housing.