WEAKLY COUPLED FEW-MODE FIBERS FOR SPACE-DIVISION MULTIPLEXING

摘要

A few mode optical fiber that includes an optical core and an optical cladding surrounding the optical core. The FMF has a step-index profile. The optical core has a core outer radius R₁≥7.5 μm and a core refractive index difference Δn₁ such that 14.5×10⁻³Δn₁24×10⁻³. The optical cladding comprises:an index ring with: a ring inner radius R_r1 between 12 μm and 19 μm;a ring refractive index difference Δn_r such that Δn₁/Δn_r is between 2 and 4;a ring volume V_ring=πΔn_r(Rr₂²−Rr₁²) between 1.8 μm² and 4.1 μm² where R_r2 is the ring outer radius;an inner cladding between the optical core and the index ring, with an inner cladding inner radius R_i1 and an inner cladding outer radius R_i2, the inner cladding having an inner cladding refractive index difference Δ_clad1 between −1.0×10⁻³ and 1.0×10⁻³.