Abstract: A method for manufacturing a preform for a multicore fiber, including stacking (S1) a plurality of core rods and a plurality of silica-based filler rods in a tube; collapsing (S2) the tube around the stack of core rods and silica-based filler rods, forming a collapsed stack; depositing (S3) a layer of silica around the collapsed stack; removing (S4) at least part of the deposited layer of silica. The preferential process for depositing a layer of silica around the collapsed stack and removing at least part of the deposited layer of silica is Advanced Plasma and Vapor Deposition.

Abstract: The invention relates to an optical fiber 1 comprising a core 2 and a cladding 3 surrounding the core 2 and having an outer diameter of 125 ?m, the optical fiber 1 comprising a cured primary coating 4 directly surrounding the cladding 3 and a cured secondary coating 5 directly surrounding the cured primary coating 4, said cured primary coating 4 having a thickness t1 between 10 and 18 ?m and an in-situ tensile modulus Emod1 between 0.10 and 0.18 MPa, said cured secondary coating 5 having a thickness t2 between 10 microns and 18 microns and an in-situ tensile modulus Emod2 between 700 and 1200 MPa, wherein said first and second thicknesses and said first and second in-situ tensile moduli satisfy the following equation: 4%<(t1×t2×E mod1×E mod23)/(t1_norm×t2_norm×E mod1_norm×E mod2_norm3)<50%.

Abstract: The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: launching a reference pulse of light with a wavelength ?t from a light source into said optical component, collecting light signal output by said optical component into a Mode Group Separating optical fiber; detecting light signal output by said Mode Group Separating optical fiber. The Mode Group Separating optical fiber is a multimode fiber with an ?-profile graded index core with an ?-value chosen such that said fiber satisfies the following criterion at the wavelength ?t: ? ?? ? . L ? ? ? T REF > 4 where: ?? is a time delay difference between consecutive mode groups; L is a length of said fiber; ?TREF is a Full Width at Quarter Maximum of said reference pulse.

Abstract: The invention concerns a bending-loss single mode optical fibre having a Mode Field Diameter at 1310 nm greater than or equal to 9 microns and having a core and a cladding, the core refractive index profile having a trapezoid-like shape. According to an aspect of the invention, the cladding comprises a shallow trench with a refractive index difference Ant between ?2×10?3; and ?0.9×10?3, and: the trapezoid ratio r0/r1 of the core is between 0.1 and 0.6, preferably, between 0.2 and 0.5, more preferably between 0.25 and 0.45; the core surface integral Formula (I) is between 20.10 3 ?m and 24.10?3 ?m and the cladding surface integral Formula (II) is between ?25×10?3 ?m and ?9×10?3 ?m, where ?n(r) is the refractive-index difference with respect to said outer cladding as a function of the radius r, and said single mode optical fibre fulfils the following criterion: 25.7×10?3?V01?0.2326V02?26.8×10?3.

Abstract: The invention relates to an optical fiber 1 comprising a core 2 and a cladding 3 surrounding the core 2 and having an outer diameter of 125 ?m, the optical fiber 1 comprising a cured primary coating 4 directly surrounding the cladding 3 and a cured secondary coating 5 directly surrounding the cured primary coating 4, said cured primary coating 4 having a thickness t1 between 10 and 18 ?m and an in-situ tensile modulus Emod1 between 0.10 and 0.18 MPa, said cured secondary coating 5 having a thickness t2 between 10 microns and 18 microns and an in-situ tensile modulus Emod2 between 700 and 1200 MPa, wherein said first and second thicknesses and said first and second in-situ tensile moduli satisfy the following equation: 4%<(t1×t2×E mod1×E mod23)/(t1_norm×t2_norm×E mod1_norm×E mod2_norm3)<50%.

Abstract: A few-mode optical fiber including a core's refractive-index profile ?n(r) of trapezoid-like shape. The optical core having a center part of radius R1 and a transition part ranges from the radius R1 to a radius R2, such that R2>R1 with R2 between 6.8 and 11.5 ?m, said refractive-index profile being defined by a surface integral of the core index profile of between 180×10?3 and 270×10?3 ?m; a transition slope S of between 1.7×10?3 and 12×10?3 ?m?1; with ?n1 and ?n2 the refractive-index difference respectively of the center part of the optical core and of the cladding part adjacent to the optical core, with respect to the outer optical cladding.

Abstract: 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 ?m and a core refractive index difference ?n1 such that 14.5×10?3<?n1<24×10?3. The optical cladding comprises: an index ring with: a ring inner radius Rr1 between 12 ?m and 19 ?m; a ring refractive index difference ?nr such that ?n1/?nr is between 2 and 4; a ring volume Vring=??nr(Rr22?Rr12) between 1.8 ?m2 and 4.1 ?m2 where Rr2 is the ring outer radius; an inner cladding between the optical core and the index ring, with an inner cladding inner radius Ri1 and an inner cladding outer radius Ri2, the inner cladding having an inner cladding refractive index difference ?nclad1 between ?1.0×10?3 and 1.0×10?3.

Abstract: The invention relates to an optical fiber 1 comprising a core 2 and a cladding 3 surrounding the core 2 and having an outer diameter of 125 ?m, the optical fiber 1 comprising a cured primary coating 4 directly surrounding the cladding 3 and a cured secondary coating 5 directly surrounding the cured primary coating 4, said cured primary coating 4 having a thickness t1 between 10 and 18 ?m and an in-situ tensile modulus Emod1 between 0.10 and 0.18 MPa, said cured secondary coating 5 having a thickness t2 lower or equal to 18 ?m and an in-situ tensile modulus Emod2 between 700 and 1200 MPa, wherein said first and second thicknesses and said first and second in-situ tensile moduli satisfy the following equation: 4%<(t1×t2×Emod1×Emod23)/(t1_norm×t2_norm×Emod1_norm×Emod2_norm3)<50%.

Abstract: A multimode optical fiber (10) comprises an a-profile graded index core, a trench (13) surrounding the core (11) and an intermediate cladding (12) between the core and the trench. Such a multimode optical fiber (10) has: —A mode carrying capacity between 54 and 68 LP modes at 1060 nm, defined by a specific relationship between the numerical aperture of the core and the core radius, —A defined relationship between trench, core and intermediate cladding parameters to achieve a high bandwidth and low bend-loss at 1060 nm, and—A core radius between 24 and 26 ?m, a numerical aperture between 0.190 and 0.225 and a value of a between 2.01 and 2.05 to retain compatibility with legacy fibers.

Abstract: An optical fiber having an optical core and an optical cladding surrounding the optical core, the optical core having a single ? graded-index profile with ??1, ? being a non-dimensional parameter that defines the index profile shape of the optical core, and the optical core having a maximal refractive index nco at its center; the optical cladding has at its outer edge a refractive index nCl, and comprises a region of depressed refractive index ntrench, called a trench, with a negative refractive index difference ?nt=ntrench?nCl with respect to said optical cladding, the trench having an outer radius Rtrench. The optical core and cladding are configured to support propagation of at least six spatial modes and at maximum fifty-five spatial modes at an operating wavelength ?op between, and including, 1460 nm and 1675 nm, and the optical core satisfies an ovality criterion between 0.05 and 0.

Abstract: The invention concerns a bending-loss single mode optical fibre having a Mode Field Diameter at 1310 nm greater than or equal to 9 microns and having a core and a cladding, the core refractive index profile having a trapezoid-like shape. According to an aspect of the invention, the cladding comprises a shallow trench with a refractive index difference Ant between ?2×10?3; and ?0.9×10?3, and: the trapezoid ratio r0/r1 of the core is between 0.1 and 0.6, preferably, between 0.2 and 0.5. more preferably between 0.25 and 0.45; the core surface integral Formula (I) is between 20.10 3 ?m and 24. 10?3 ?m and the cladding surface integral Formula (II) is between ?25×10?3 ?m and ?9×10?3 ?m, where ?n(r) is the refractive-index difference with respect to said outer cladding as a function of the radius r, and said single mode optical fibre fulfils the following criterion: 25.7×10?3?V01?0.2326V02?26.8×10?3.

Abstract: 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 ?m and a core refractive index difference ?n1 such that 14.5×10?3<?n1<24×10?3. The optical cladding comprises: an index ring with: a ring inner radius Rr1 between 12 ?m and 19 ?m; a ring refractive index difference ?nr such that ?n1/?nr is between 2 and 4; a ring volume Vring=??nr(Rr22?Rr12) between 1.8 ?m2 and 4.1 ?m2 where Rr2 is the ring outer radius; an inner cladding between the optical core and the index ring, with an inner cladding inner radius Ri1 and an inner cladding outer radius Ri2, the inner cladding having an inner cladding refractive index difference ?clad1 between ?1.0×10?3 and 1.0×10?3.

Abstract: An optical fiber having an optical core and an optical cladding surrounding the optical core, the optical core having a single ? graded-index profile with ??1, ? being a non-dimensional parameter that defines the index profile shape of the optical core, and the optical core having a maximal refractive index nco at its center; the optical cladding has at its outer edge a refractive index nCl, and comprises a region of depressed refractive index ntrench, called a trench, with a negative refractive index difference ?nt=ntrench?nCl with respect to said optical cladding, the trench having an outer radius Rtrench. The optical core and cladding are configured to support propagation of at least six spatial modes and at maximum fifty-five spatial modes at an operating wavelength ?op between, and including, 1460 nm and 1675 nm, and the optical core satisfies an ovality criterion between 0.05 and 0.

Abstract: A few-mode optical fiber including a core's refractive-index profile ?n(r) of trapezoid-like shape. The optical core having a center part of radius R1 and a transition part ranges from the radius R1 to a radius R2, such that R2>R1 with R2 between 6.8 and 11.5 ?m, said refractive-index profile being defined by a surface integral of the core index profile of between 180×10?3 and 270×10?3 ?m; a transition slope S of between 1.7×10?3 and 12×10?3 ?m?1; with ?n1 and ?n2 the refractive-index difference respectively of the center part of the optical core and of the cladding part adjacent to the optical core, with respect to the outer optical cladding.

Abstract: The invention relates to a method for qualifying the actual effective modal bandwidth of a multimode optical fiber over a predetermined wavelength range, comprising the steps of: carrying out (30) a Dispersion Modal Delay (DMD) measurement of the multimode optical fiber at a single wavelength to obtain an actual DMD plot; generating (32) at least two distinct modified DMD plots from the actual DMD plot, each modified DMD plot being generated by applying to the recorded traces a temporal delay ?t that increases in absolute values with the radial offset value roffset, each modified DMD plot being associated with a predetermined bandwidth threshold (S1; S2); for each modified DMD plot, computing (33) an effective modal bandwidth as a function of said modified DMD plot and comparing (34) the computed effective modal bandwidth (EMBc1; EMBc2) with the bandwidth threshold value to which the modified DMD plot is associated; (35) qualifying the actual effective modal bandwidth as a function of results from the compari

Abstract: A multimode optical fiber (10) comprises an a-profile graded index core, a trench (13) surrounding the core (11) and an intermediate cladding (12) between the core and the trench. Such a multimode optical fiber (10) has: A mode carrying capacity between 54 and 68 LP modes at 1060 nm, defined by a specific relationship between the numerical aperture of the core and the core radius, A defined relationship between trench, core and intermediate cladding parameters to achieve a high bandwidth and low bend-loss at 1060 nm, and A core radius between 24 and 26 ?m, a numerical aperture between 0.190 and 0.225 and a value of a between 2.01 and 2.05 to retain compatibility with legacy fibers.

Abstract: The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: launching a reference pulse of light with a wavelength ?t from a light source into said optical component, collecting light signal output by said optical component into a Mode Group Separating optical fiber; detecting light signal output by said Mode Group Separating optical fiber. The Mode Group Separating optical fiber is a multimode fiber with an ?-profile graded index core with an ?-value chosen such that said fiber satisfies the following criterion at the wavelength ?t: ? ?? ? . L ? ? ? T REF > 4 where: ?? is a time delay difference between consecutive mode groups; L is a length of said fiber; ?TREF is a Full Width at Quarter Maximum of said reference pulse.

Abstract: A method for selecting wide-band multimode optical fibers from a single wavelength, the method comprising the following steps of, for each multimode optical fiber obtaining a first DMD plot using a measurement of DMD carried out at a first single wavelength, obtaining from the first DMD plot, a first multimode fiber specification parameter; and for each fiber: obtaining from the first DMD plot, a curve representative of a radial offset delay, called ROD curve, as a function of the radial offset value; applying a linear fit on the ROD curve for at least two radial offset value ranges; obtaining from the linear fit and for each radial offset value range, an average radial offset delay slope, called ROD slope; selecting the multimode optical fibers meeting a first predetermined specification criterion for the first multimode fiber performance parameter, and for which the at least two computed ROD slopes meet a predetermined slope criterion.

Abstract: A method of qualifying an effective bandwidth of a multimode optical fiber at a first wavelength ?1, using DMD data of the fiber measured a second wavelength ?2. Data representative of a Radial Offset Delay, a Radial Offset Bandwidth and a Relative Radial Coupled Power of the fiber are derived from the DMD data at the second wavelength ?2. A transformation is performed on the ROD data and ROB data at the second wavelength ?2 to obtain corresponding ROD data and ROB data at the first wavelength ?1. An effective bandwidth of the fiber at the second wavelength ?2 is computed using the ROD data and the ROB data at the first wavelength ?1 and the {tilde over (P)}DMD data at the second wavelength ?2.

Abstract: The invention concerns a method for characterizing mode group properties of multimodal light traveling through an optical component, comprising: providing a Mode Group Separating optical fiber in an optical path between a light source and said optical component; launching reference pulses of light with a wavelength ?t from said light source through said Mode Group Separating optical fiber into said optical component at discrete intervals between a core center and a core radius of said fiber. The Mode Group Separating optical fiber is a multimode fiber with an ?-profile graded index core with an ?-value chosen such that said fiber satisfies the following criterion at the wavelength ?t: ? ?? ? · L ? ? ? T REF > 4 where: ?? is a time delay difference between consecutive mode groups; L is a length of said fiber; ?TREF is a Full Width at Quarter Maximum of said reference pulses.