摘要 |
The invention is related to an optical waveguide device comprising a length of fiber including a monomode core having a refraction index of n<SUB>co</SUB>, a photosensitivity of S<SUB>co </SUB>and a radius R<SUB>co </SUB> and an internal cladding with an refractive index of n<SUB>cl</SUB>, a photosensitivity of S<SUB>cl </SUB>and a radius of R<SUB>cl</SUB>, and a outer cladding surrounding the internal cladding with an refractive index that allows the existence of multiple cladding modes, and a slanted Bragg grating with an effective tilt angle of theta written in core and inner cladding of the optical waveguide, coupling the fundamental mode into several cladding modes where R<SUB>cl</SUB><=2.5 R<SUB>co </SUB>and the S<SUB>co</SUB><=S<SUB>cl</SUB>.
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