Few mode optical fiber comprising an optical core and an optical cladding surrounding the optical core, said optical fiber having a step-index profile and said optical cladding having at its outer edge a refractive index n Cl, wherein said optical core has a core outer radius R 1 ≥ 7.5 μm and said optical cladding comprises: - an index ring; - an inner cladding between said optical core and said index ring, with an inner cladding inner radius R i 1 substantially equal to said core outer radius R 1 and an inner cladding outer radius R i 2; characterized in that said optical core has a core refractive index difference Δ n 1 with respect to said optical cladding outer edge refractive index n Cl such that 14.5 × 10 -3 < Δ n 1 < 24 × 10 -3, and in that said index ring has: ∘ a ring inner radius R r 1 between 12 μm and 19 μm and substantially equal to said inner cladding outer radius R i 2; ∘ a ring refractive index difference Δ n r with respect to said optical cladding outer edge refractive index n Cl such that Δ n 1 Δ n r which is between 2 and 4; ∘ a ring volume V ring = π Δ n r Rr 2 2 − Rr 1 2 between 1.8 μm 2 and 4.1 μm 2 where R r 2 is the ring outer radius; and in that said inner cladding has an inner cladding refractive index difference Δ n clad 1 with respect to said optical cladding outer edge refractive index n Cl between -1.0 × 10 -3 and 1.0 × 10 -3, said refractive index differences Δ n 1, Δ n r and Δ n clad 1 being determined at a wavelength λ = 633nm. said optical fiber having a step-index profile and said optical cladding having at its outer edge a refractive index n Cl, wherein said optical core has a core outer radius R 1 ≥ 7.5 μm and said optical cladding comprises: - an index ring; - an inner cladding between said optical core and said index ring, with an inner cladding inner radius R i 1 substantially equal to said core outer radius R 1 and an inner cladding outer radius R i 2; characterized in that said optical core has a core refractive index difference Δ n 1 with respect to said optical cladding outer edge refractive index n Cl such that 14.5 × 10 -3 < Δ n 1 < 24 × 10 -3, and in that said index ring has: ∘ a ring inner radius R r 1 between 12 μm and 19 μm and substantially equal to said inner cladding outer radius R i 2; ∘ a ring refractive index difference Δ n r with respect to said optical cladding outer edge refractive index n Cl such that Δ n 1 Δ n r which is between 2 and 4; ∘ a ring volume V ring = π Δ n r Rr 2 2 − Rr 1 2 between 1.8 μm 2 and 4.1 μm 2 where R r 2 is the ring outer radius; and in that said inner cladding has an inner cladding refractive index difference Δ n clad 1 with respect to said optical cladding outer edge refractive index n Cl between -1.0 × 10 -3 and 1.0 × 10 -3, said refractive index differences Δ n 1, Δ n r and Δ n clad 1 being determined at a wavelength λ = 633nm. - an index ring; - an inner cladding between said optical core and said index ring, with an inner cladding inner radius R i 1 substantially equal to said core outer radius R 1 and an inner cladding outer radius R i 2; characterized in that said optical core has a core refractive index difference Δ n 1 with respect to said optical cladding outer edge refractive index n Cl such that 14.5 × 10 -3 < Δ n 1 < 24 × 10 -3, and in that said index ring has: ∘ a ring inner radius R r 1 between 12 μm and 19 μm and substantially equal to said inner cladding outer radius R i 2; ∘ a ring refractive index difference Δ n r with respect to said optical cladding outer edge refractive index n Cl such that Δ n 1 Δ n r which is between 2 and 4; ∘ a ring volume V ring = π Δ n r Rr 2 2 − Rr 1 2 between 1.8 μm 2 and 4.1 μm 2 where R r 2 is the ring outer radius; and in that said inner cladding has an inner cladding refractive index difference Δ n clad 1 with respect to said optical cladding outer edge refractive index n Cl between -1.0 × 10 -3 and 1.0 × 10 -3, said refractive index differences Δ n 1, Δ n r and Δ n clad 1 being determined at a wavelength λ = 633nm. characterized in that said optical core has a core refractive index difference Δ n 1 with respect to said optical cladding outer edge refractive index n Cl such that 14.5 × 10 -3 < Δ n 1 < 24 × 10 -3, and in that said index ring has: ∘ a ring inner radius R r 1 between 12 μm and 19 μm and substantially equal to said inner cladding outer radius R i 2; ∘ a ring refractive index difference Δ n r with respect to said optical cladding outer edge refractive index n Cl such that Δ n 1 Δ n r which is between 2 and 4; ∘ a ring volume V ring = π Δ n r Rr 2 2 − Rr 1 2 between 1.8 μm 2 and 4.1 μm 2 where R r 2 is the ring outer radius; ∘ a ring inner radius R r 1 between 12 μm and 19 μm and substantially equal to said inner cladding outer radius R i 2; ∘ a ring refractive index difference Δ n r with respect to said optical cladding outer edge refractive index n Cl such that Δ n 1 Δ n r which is between 2 and 4; ∘ a ring volume V ring = π Δ n r Rr 2 2 − Rr 1 2 between 1.8 μm 2 and 4.1 μm 2 where R r 2 is the ring outer radius; and in that said inner cladding has an inner cladding refractive index difference Δ n clad 1 with respect to said optical cladding outer edge refractive index n Cl between -1.0 × 10 -3 and 1.0 × 10 -3, said refractive index differences Δ n 1, Δ n r and Δ n clad 1 being determined at a wavelength λ = 633nm.