Abstract: A multimode optical fiber includes a central core surrounded by an outer cladding. The central core has a graded-index profile with respect to the outer cladding and an outer radius r1 of between about 30 microns and 50 microns (e.g., between about 35 microns and 45 microns). The optical fiber also includes an inner cladding positioned between the central core and the outer cladding, and a depressed trench positioned between the inner cladding and the outer cladding. The multimode optical fiber exhibits reduced bending losses.

Abstract: It is proposed a home optical data network formed of an optical fiber comprising an optical core and an optical cladding surrounding the optical core, the optical core having a refractive graded-index profile with a minimal refractive index n1 and a maximal refractive index n0, said optical fiber being such that it has a numerical aperture NA and an optical core radius a satisfying a criterion C of quality of optical communications defined by the following equation: C = NA - 0.02 × a where ? : NA = n 0 2 - n 1 2 = n 0 · 2 ? ? ? ? with ? ? ? = n 0 2 - n 1 2 2 ? n 0 2 , ? is the normalized refractive index difference, and in that said minimal and maximal refractive indexes n1, n0 and said optical core radius a are chosen such that NA>0.20, a>10 ?m and |C|<0.20.

Abstract: A hybrid optical fiber integrates features of multimode optical fibers and single-mode optical fibers. The hybrid optical fiber possesses an optical core having a first core region and a second core region to provide improved optical mode coupling ratio for single-mode transmission while maintaining a broad bandwidth for multimode transmission. The hybrid optical fiber's optical core may optionally include a depressed trench positioned between the optical core's first core region and the optical core's second core region to reduce modal dispersion and to improve modal bandwidth during multimode transmissions.

Abstract: The invention relates to an optical fiber comprising an optical core and an optical cladding surrounding the optical core, the optical core having a single ? graded-index profile with ??1, and the optical core having a radius R1 and a maximal refractive index n0, said optical cladding having a refractive index nCl. Said optical cladding comprises a region of depressed refractive index ntrench, having an inner radius R2, with R2?R1, and an outer radius R3, with R3>R2. According to embodiments of the invention, the ?-value of said graded index profile and the optical core radius R1 are chosen such that R1?13.5 ?m and so as to satisfy a criterion C of quality. Thus, the invention provides a few-mode optical fiber, which allow guiding an increased number of LP modes as compared to prior art FMFs, while reaching the lowest Differential Mode Group Delay. The system reach is thus increased over prior art.

Abstract: A multimode optical fiber is provides, which includes an optical core and an optical cladding surrounding the optical core. The optical core has a refractive graded-index profile. The optical cladding includes: an inner layer surrounding the optical core, an intermediate layer, called a “depressed trench”, surrounding the inner layer, and an outer layer surrounding the depressed trench and having a constant refractive index. The depressed trench has a width W and a negative refractive index difference ?nt with respect to the outer layer, and is designed so as to satisfy the following inequality: |0.585677?114.681×S+13.7287×S2+18.7343×S×W?4.61112×S×?nt.103?0.913789×W×?nt.103|+2×W×?nt.103<?30 wherein: S is the width of the inner cladding, which is included between 0.6 ?m and 1.6 ?m; ?nt is included between ?11.10?3 and ?4.10?3; and W×?nt.103 is lower than ?25 ?m.

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.

Abstract: It is proposed an optical fiber including an optical core and an optical cladding surrounding the optical core. The optical core has a refractive graded-index profile with a minimal refractive index n1 and a maximal refractive index n0. The optical fiber has a numerical aperture NA and an optical core radius ? satisfying a criterion C of quality of optical communications defined by the following equation: C=NA?0.02×a where: NA=?{square root over (n02?n12)}=n0·?{square root over (2?)} with ? = n 0 2 - n 1 2 2 ? ? n 0 2 , ? is the normalized refractive index difference. The minimal and maximal refractive indexes n1, n0 and the optical core radius a are chosen such that NA>0.20, a>10 ?m and |C|<0.20.

Abstract: A hybrid optical fiber integrates features of multimode optical fibers and single-mode optical fibers. The hybrid optical fiber possesses an optical core having a first core region and a second core region to provide improved optical mode coupling ratio for single-mode transmission while maintaining a broad bandwidth for multimode transmission. The hybrid optical fiber's optical core may optionally include a depressed trench positioned between the optical core's first core region and the optical core's second core region to reduce modal dispersion and to improve modal bandwidth during multimode transmissions.

Abstract: The invention concerns a single mode optical fibre having a core and a cladding, the core refractive index profile having a trapezoid-like shape. According to an aspect of the invention, the transition part of the trapezoid-like core refractive index profile is obtained by gradually changing a concentration of at least two dopants from a concentration in said centre part of said core to a concentration in a cladding part adjacent to said core.

Abstract: The invention concerns a multimode optical fiber, with a graded-index core co-doped with at least fluorine F and germanium GeO2 and a refractive index profile with at least two ?-values. According to the invention, the concentration of fluorine F at the core center ([F]r=0) is between 0 and 3 wt % and the concentration of fluorine F at the core outer radius ([F],a) is between 0.5 wt % and 5.5 wt %, with [F]r=a?[F]r=>0.4 wt %. For wavelengths comprised between 850 nm and 1100 nm, said multimode optical fiber has an overfilled launch bandwidth (OFL-BW) greater than 3500 MHz·km and a calculated effective modal bandwidth (EMBc) greater than 4700 MHz·km over a continuous operating wavelength range greater than 150 nm.

Abstract: A multimode optical fiber includes a central core surrounded by an outer cladding. The central core has a graded-index profile with respect to the outer cladding and an outer radius r1 of between about 30 microns and 50 microns (e.g., between about 35 microns and 45 microns). The optical fiber also includes an inner cladding positioned between the central core and the outer cladding, and a depressed trench positioned between the inner cladding and the outer cladding. The multimode optical fiber exhibits reduced bending losses.

Abstract: The invention concerns a method of characterizing a multimode optical fiber link comprising a light source and a multimode fiber, which comprises: a step (170) of characterizing the multimode fiber using a measurement of the Dispersion Modal Delay (DMD) and delivering fiber characteristic data; a step (171) of characterizing the light source by at least three source characteristic curves showing three parameters of the source as a function of a fiber radius r and obtained by a technique similar to the DMD measurement; a step (173) of computing an Effective Bandwidth (EB) of the link, comprising calculating (172) a transfer function using both the fiber characteristic data and each of said source characteristic curves.

Abstract: The invention relates to an optical link comprising N optical fibers, with N?2. Each optical fiber comprises an optical core and an optical cladding surrounding the optical core, the optical core having a single ?i graded-index profile with ?i?1, and the optical core having a radius R1i, where i E [1; N] is an index designating said optical fiber. Said optical cladding comprises a region of depressed refractive index ntrenchi, called a trench, surrounding the optical core. According to embodiments of the invention, for all optical fibers in said link, said optical core radius R1i and said length Li are chosen such that R1i?13.5 ?m and so as to satisfy a criterion C of quality. Thus, the invention provides a few-mode optical fiber link, which allow guiding an increased number of LP modes as compared to prior art FMF links, while reaching low Differential Mode Group Delay.

Abstract: The invention relates to an optical fiber comprising an optical core and an optical cladding surrounding the optical core, the optical core having a single ? graded-index profile with ??1, and the optical core having a radius R1 and a maximal refractive index n0, said optical cladding having a refractive index nCl. Said optical cladding comprises a region of depressed refractive index ntrench, having an inner radius R2, with R2?R1, and an outer radius R3, with R3>R2. According to embodiments of the invention, the ?-value of said graded index profile and the optical core radius R1 are chosen such that R1?13.5 ?m and so as to satisfy a criterion C of quality. Thus, the invention provides a few-mode optical fiber, which allow guiding an increased number of LP modes as compared to prior art FMFs, while reaching the lowest Differential Mode Group Delay. The system reach is thus increased over prior art.

Abstract: A method of assessing the power penalty at a given bit error rate of a multimode fiber including measuring a set of elementary fiber responses corresponding to different offset launches of light over the core radius into the multimode fiber, generating a global fiber response by applying, to the set of elementary fiber responses, a set of weighting coefficients and delays depending on the different offset launches of the elementary fiber responses, and computing a parameter representative of a fiber power penalty from the global fiber response, wherein the set of weighting coefficients includes several subsets of weighting coefficients time delayed relative to one another, wherein at least one relative time delay is not set to zero, and wherein weighting coefficients of each subset depend on the different offset launches of the elementary fiber responses.

Abstract: A multimode optical fiber is provides, which includes an optical core and an optical cladding surrounding the optical core. The optical core has a refractive graded-index profile. The optical cladding includes: an inner layer surrounding the optical core, an intermediate layer, called a “depressed trench”, surrounding the inner layer, and an outer layer surrounding the depressed trench and having a constant refractive index. The depressed trench has a width W and a negative refractive index difference ?nt with respect to the outer layer, and is designed so as to satisfy the following inequality: |0.585677?114.681×S+13.7287×S2+18.7343×S×W?4.61112×S×?nt·103?0.913789×W×?nt·103|+2×W×?nt·103<?30 wherein: S is the width of the inner cladding, which is included between 0.6 ?m and 1.6 ?m; ?nt is included between ?11.10?3 and ?4.10?3; and W×?nt·103 is lower than ?25 ?m.

Abstract: A multimode optical fiber includes a central core surrounded by an outer cladding. The central core has a graded-index profile with respect to the outer cladding and an outer radius r1 of between about 30 microns and 50 microns (e.g., between about 35 microns and 45 microns). The optical fiber also includes an inner cladding positioned between the central core and the outer cladding, and a depressed trench positioned between the inner cladding and the outer cladding. The multimode optical fiber exhibits reduced bending losses.

Abstract: It is proposed an optical fiber including an optical core and an optical cladding surrounding the optical core. The optical core has a refractive graded-index profile with a minimal refractive index n1 and a maximal refractive index n0. The optical fiber has a numerical aperture NA and an optical core radius a satisfying a criterion C of quality of optical communications defined by the following equation: C=NA?0.02×a where: NA=?{square root over (n02?n12)}=n0·?{square root over (2?)} with ? = n 0 2 - n 1 2 2 ? ? n 0 2 , ? is the normalized refractive index difference. The minimal and maximal refractive indexes n1, n0 and the optical core radius a are chosen such that NA>0.20, a>10 ?m and |C|<0.20.

Abstract: A trench-assisted, multimode optical fiber includes a central core having an alpha refractive index profile with respect to an outer cladding. The optical fiber also includes an inner cladding, a depressed trench, and an outer cladding. The optical fiber achieves reduced bending losses and a high bandwidth.

Abstract: A non-zero dispersion shifted optical fiber (NZDSF) includes a central core, an inner cladding, and an outer cladding. The central core has an outer radius r1 and a maximum refractive index difference Dn1 with respect to the outer cladding. The inner cladding includes a first intermediate cladding and a buried trench. The first intermediate cladding has an outer radius r2 and a refractive index difference Dn2 with respect to the outer cladding. The buried trench has an outer radius r3, a width w3, and a negative refractive index difference Dn3 with respect to the outer cladding. In some embodiments, the inner cladding includes a second intermediate cladding having an outer radius r4 and a refractive index difference Dn4 with respect to the outer cladding. For a radius of curvature of 30 millimeters at a wavelength of 1625 nanometers, the optical fiber typically exhibits bending losses of about 0.5 dB/100 turns or less.