Abstract: A multimode optical fiber is drawn form an optical fiber preform, and during said drawing step, a series of perturbations are imparted to the fiber along the length of the optical fiber, said perturbations exhibiting a non-constant amplitude or repeat period.

Abstract: One embodiment of a single mode optical fiber includes: a graded index central core region having outer radius r1 and relative refractive index ?1; a cladding region comprising (i) a first inner cladding region having an outer radius r2<10 microns and relative refractive index ?2 and 0.65?r1/r2?1; (ii) and a second inner cladding region (i.e., trench) having an outer radius r3>10 microns and comprising a minimum relative refractive index ?3, wherein said second inner cladding region has at least one region with a relative refractive index delta that becomes more negative with increasing radius; and (iii) an outer cladding region surrounding the second inner cladding region and comprising relative refractive index ?4, wherein ?1>?2>?3, ?3<?4.

Abstract: There is provided an optical waveguide comprising an optical core having transverse sides, the optical core extending along a curved path; an optical cladding on the transverse sides of the optical core, wherein the distribution of the optical cladding on the transverse sides of the optical core is asymmetric about the centre of the core.

Abstract: According to some embodiments a few moded optical fiber includes a glass core structured to provide light amplification at an amplification wavelength and a cladding surrounding the core. According to some embodiments the core of the few moded optical fiber includes a portion that has an average concentration of rare earth dopant which is lower by at least 30%, and preferably by at least 50%, than the average concentration of the rare earth dopant at another portion of the core that is situated further from the core center.

Abstract: The polarization-maintaining fiber of the invention includes a core (1) made of germanium doped silica glass; a stress-applying part (3) made of boron doped silica glass; a cladding (2) made of pure silica glass; and a polyimide coating layer (4) with a thickness of 10 ?m or less that surrounds the outer periphery of the cladding (2).

Abstract: The present invention embraces an optical fiber that includes a central core having an alpha refractive index profile with respect to an outer optical cladding. The optical fiber also includes an inner cladding and a buried trench. The central core includes a core matrix doped with at least fluorine and a dopant element that increases refractive index. The optical fiber typically has reduced bending losses and cladding effect as well as a high bandwidth at the wavelengths of 850 nanometers and 1300 nanometers for high-data-rate applications.

Abstract: In various embodiments, an optical element, e.g., an optical fiber, may be configured to compensate for thermal lensing. For example, thermal lensing may be caused by light power dissipation within an optical fiber, which may include a fiber core that guides amplified light along the longitudinal dimension of the fiber core. Thermal lensing from a thermally induced change in material refractive index as a function of position along dimensions perpendicular to the fiber's longitudinal dimension may be at least partially compensated or offset when light is guided by the fiber core by a designed-in effective refractive index profile selected such that the designed-in material refractive index of the fiber core changes as a function of transverse position within the fiber core, or by selection of a favorable cross-sectional core shape in a plane perpendicular to the longitudinal dimension of the fiber core.

Abstract: An optical fiber, including (i) an inner core having an ?-power refractive index profile, (ii) an outer core having a refractive index of n1?, and (iii) a cladding having a refractive index of n2 (n1?<n2<n1), is configured such that a depth of a trench, defined by n2?n1?, is sufficiently increased.

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 22 microns and 28 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: Methods of fabricating light focusing elements for use in a fiber optic communications system are disclosed in which a plurality of light focusing elements are formed on or in a top surface of a substrate. The substrate is then diced to singulate the light focusing elements.

Abstract: [Object] The present invention has the object of providing an optical fiber enabling high-speed communication, that exhibits superior transparency and excellent flexibility, and that includes trichloroethyl methacrylate as a main component of the core portion monomer. [Means for Solving Problem] An optical fiber configured from a core portion and a cladding portion disposed on an outer periphery of the core portion, wherein the core portion is formed by a main constituent component of a polymer of monomers that include at least 70 wt % of trichloroethyl methacrylate (TCEMA), the cladding portion is formed by a main constituent component of a polymer of monomers which include at least 20 wt % of methyl methacrylate (MMA).

Abstract: One exemplary multimode optical fiber includes a graded index glass core having a diameter in the range of 41 microns to 80 microns, a graded index having an alpha less than 2.04 and a maximum relative refractive index in the range between 0.6% and 1.8%. The cladding includes a depressed-index annular portion. The fiber has an overfilled bandwidth greater than 2.5 GHz-km at at least one wavelength between 1200 nm and 1700 nm.

Abstract: A multimode optical fiber includes a graded index glass core having a diameter in the range of 41 microns to 80 microns, a graded index having an alpha less than 2.04 and a maximum relative refractive index in the range between 0.6% and 1.8%. The cladding includes a depressed-index annular portion. The fiber has an overfilled bandwidth greater than 2.5 GHz-km at 1310 nm.

Abstract: A method of coupling a spliceable optical fiber includes (A) providing the spliceable optical fiber, the spliceable optical fiber including (a) a core region; and (b) a microstructured cladding region. The cladding region surrounds the core region and includes (b1) an inner cladding region having a refractive index formed by inner cladding features arranged in an inner cladding background material with a refractive index n1, the inner cladding features including thermally collapsible holes or voids, and (b2) an outer cladding region with an outer cladding background material with a refractive index n2, the spliceable optical fiber having at least one end. (B) Collapsing the thermally collapsible holes or voids by heating the at least one end of the spliceable optical fiber thereby increasing the refractive index of the inner cladding providing an expanded core. And, (C) coupling the collapsed spliceable optical fiber end to the optical component.

Abstract: One embodiment of a single mode optical fiber includes: a graded index central core region having outer radius r1 and refractive index ?1; a cladding region comprising (i) a first inner cladding region having an outer radius r2<10 microns and refractive index ?2 and 0.65?r1/r2?1; (ii) and a second inner cladding region having an outer radius r3>10 microns and comprising a minimum refractive index ?3, wherein said second cladding region has at least one region with a refractive index delta that becomes more negative with increasing radius; and (iii) an outer cladding region surrounding the inner cladding region and comprising refractive index ?4, wherein ?1>?2>?3, ?3<?4.

Abstract: A graded index multimode optical fiber comprising: (a) a silica core doped with germania, and at least one co-dopant, comprising one of P2O5 or F or B2O3, the core extending to outermost core radius, r1 and having a dual alpha, ?1; (b) a low index inner cladding surrounding the core and off-set from said core; (c) an outer cladding surrounding and in contact with the inner cladding, such that at least the region of the inner cladding off-set from said core has a lower refractive index than the outer cladding. The center germania concentration at the centerline, CGe1, is greater than or equal to 0, and an outermost germania concentration in the core CGe2, at r1 is greater than or equal to 0. The core has a center co-dopant concentration at the centerline, Cc-d1, greater than or equal to 0, and an outermost co-dopant concentration Cc-d2, at r1, wherein Cc-d2 is greater than or equal to 0.

Abstract: Between core and cladding, the side-emitting step index fibers have scattering centers that ensure the coupling out of light from the fiber. The side-emitting step index fibers are produced by preforms that contain inlay rods, in which the scattering centers are embedded and which are applied to the outer region of the fiber core during fiber drawing. Alternatively, at least one inlay tube can be used.

Abstract: An optical fiber comprising a first core, a second core, a third core, and a cladding, wherein the expressions 0.30%??1?0.45%, ?0.05%??2?0.05%, ?0.35%??3??0.15%, 2.5?b/a, 3.5 ?m?a?4.2 ?m, 9 ?m?b?13 ?m, and 4.5 ?m?c?b?7.0 ?m are satisfied, a zero-dispersion wavelength is no less than 1300 nm and no greater than 1324 nm, and transmission loss increase for a wavelength of 1550 nm when the optical fiber is wound around a mandrel with a diameter of 10 mm is no greater than 1 dB/turn.

Abstract: Various embodiments include large cores fibers that can propagate few modes or a single mode while introducing loss to higher order modes. Some of these fibers are holey fibers that comprising cladding features such as air-holes. Additional embodiments described herein include holey rods. The rods and fibers may be used in many optical systems including optical amplification systems, lasers, short pulse generators, Q-switched lasers, etc. and may be used for example for micromachining.

Abstract: The present invention relates to a multi-mode optical fiber having a structure enabling stable production and broadening of communication bandwidth as compared with the conventional structures. The multi-mode optical fiber has a core with a diameter 2a that is doped with GeO2 and chlorine. The chlorine concentration profile in the core along the diametric direction of the multi-mode optical fiber has a shape such that the chlorine concentration at a second measurement position within a range at a distance of from 0.9 a to 1.0 a from the center of the core in the radial direction thereof is higher than the chlorine concentration at a first measurement position at a distance of a/2 from the center of the core in the radial direction thereof.

Abstract: The present invention relates to a multi-mode optical fiber having a structure which can be produced with good stability with a communication bandwidth broader than that in the conventional structures, and in which both GeO2 and chlorine are added to a core thereof, and chlorine is also added to a cladding thereof. The cladding contains chlorine such that the average chlorine concentration therein becomes higher than the average chlorine concentration in the core.

Abstract: A graded index multimode optical fiber (10) includes: a core (11) having an outside diameter of 45-65 ?m; a first cladding (12) surrounding the core (11); a second cladding (13) surrounding the first cladding (12) and made of a material having a lower refractive index than the first cladding (12); and a third cladding (14) surrounding the second cladding (13) and made of a material having a higher refractive index than the second cladding (13). The ratio of the outside diameter of the first cladding (12) to the outside diameter of the core (11) is 1.15-1.25.

Abstract: A manufacturing method of a photonic band gap fiber which includes measuring a hole diameter d0 and a distance-between-holes ?0 in a preliminary experiment capillary body by first drawing a preliminary experiment preform, calculating a confinement loss to a normalized wavelength ?/? being a wavelength ? normalized by an optional distance-between-holes ? using a ratio d0/?0 and the optional distance-between-holes ? as design parameters, setting a distance-between-holes by calculating the set distance-between-holes ?1 to a desired transmission wavelength ?1 of a photonic band gap fiber to be manufactured using a value of the normalized wavelength ?/? in which the confinement loss becomes about a minimum value, and second drawing a preform for a photonic band gap fiber by using the same members as those of the preliminary experiment preform and by setting a distance-between-holes to the set distance-between-holes ?1, in a drawing temperature condition used for the first drawing.

Abstract: A LMA, single-mode optical fiber comprises a core region, an inner cladding region surrounding the core region, and an outer cladding region surrounding the inner cladding region. The inner cladding region is configured to provide bend compensation. In one embodiment the index profile of the inner cladding region is graded with a slope of ?ncore/Rb, where ncore is the refractive index of the core region, Rb is the bend radius, and ?=0.6-1.2. In addition, the inner cladding is annular and the ratio of its outer radius to its inner radius is greater than 2. In a preferred embodiment this ratio is greater than 3. The overall index profile may be symmetric or asymmetric.

Abstract: Various embodiments described herein include rare earth doped glass compositions that may be used in optical fiber and rods having large core sizes. Such optical fibers and rods may be employed in fiber lasers and amplifiers. The index of refraction of the glass may be substantially uniform and may be close to that of silica in some embodiments. Possible advantages to such features include reduction of formation of additional waveguides within the core, which becomes increasingly a problem with larger core sizes.

Abstract: A multi-mode optical waveguide fiber including a central core region having an outer radius surrounded by an inner cladding region having an outer radius, the inner cladding region having a lower index of refraction than the central core region, wherein both the central core and inner cladding regions are doped with fluorine, wherein the refractive index profile of the central core region is of the gradient index type and the central core region in the range of r?[0-ra] comprises germanium at a maximum concentration within the range of 0.5 percent by weight to 4.0 percent by weight taken at a given radius, wherein said fiber has an Overfilled Modal Bandwidth >500 MHz·km at a wavelength of 850 nm and 1300 nm, according to IEC 60793-2-10.

Abstract: The present invention relates to a multi-core optical fiber including a plurality of cores, in each of which an effective area at the wavelength of 1550 nm, a transmission loss at the wavelength of 1550 nm, a chromatic dispersion at the wavelength of 1550 nm, a cable cutoff wavelength, and a bending loss in a bending radius of 30 mm at the wavelength of 1625 nm are set so as to increase a transmission capacity in each core in a state in which a difference of the transmission loss at the wavelength of 1550 nm between different cores is controlled to at most 0.02 dB/km or less.

Abstract: A gradient-index multimode optical fiber for use as a stub fiber in an optical fiber connector is disclosed. The fiber is configured to have a minimum group index difference to minimize the adverse effects of multipath interference that can arise in a short, single-mode stub fiber that has a large group index difference. The fiber is also configured to have a mode-field diameter that is substantially the same as that of single-mode optical fibers used as stub fibers. An optical fiber connector that uses the fiber as a stub fiber is also disclosed.

Abstract: An optical fiber includes a core (1a) having an oblong rectangular or square cross section and made of quartz, a cladding (2) surrounding the core (1a), having a circular outer cross-sectional shape, having a lower refractive index than the core (1a), and made of resin, and a support layer (3) surrounding the cladding (2) and made of quartz.

Abstract: The invention relates to a bend insensitive gradient index multimode light conducting fiber comprising a leakage mode dependent optical core diameter that is uniform over its length and a numerical aperture that is uniform over its length, a core (1), an inner cladding (2), a refraction index trench (3) and an outer cladding (4), wherein the core (1) includes a core radius R1, an alpha-refraction index profile and a core refraction index difference dn1 with respect to the outer cladding (4), wherein the refraction index trench (3) includes a refraction index trench radius R3 and a trench refraction index difference dn3 with respect to the outer cladding (4), wherein the outer cladding (4) includes an outer cladding radius R4 and a refraction index between 1.40 and 1.55, wherein for a light wavelength of 850 nm and an overfilled launch (OFL), the optical core diameter for a fiber length in a range between 2 m and 300 m decreases by less than 5% and the numerical aperture decreases by less than 2.

Abstract: A few mode optical fiber comprising: a Ge-free core having an effective area Aeff of LP01 mode wherein 120 ?m2<Aeff<1000 ?m2 at 1550 nm, and a refractive index profile selected such that the core is capable of supporting the propagation and transmission of an optical signal with X number of LP modes at 1550 nm, X is an integer and 1<X?20, maximum refractive index delta of the core, ?0, wherein ?0.5%??0?0.08%; and, an annular cladding surrounding the core having a low index ring with a minimum refractive index delta ?rMIN, ?rMIN<?0 and ?rMIN??0.3 relative to pure SiO2, an outer cladding with a refractive index delta ?Outer-Clad, such that ?Outer-Clad>?rMIN; and |?0??Outer-Clad|>0.05%, the relative refractive index profile of the optical fiber is selected to provide attenuation of <0.18 dB/km at the 1550 nm, and LP11 cut off wavelength >1600 nm.

Abstract: The specification describes multimode optical fibers with specific design parameters, i.e., controlled refractive index design ratios and dimensions, which render the optical fibers largely immune to moderately severe bends. The modal structure in the optical fibers is also largely unaffected by bending, thus leaving the optical fiber bandwidth essentially unimpaired. Bend performance results were established by DMD measurements of fibers wound on mandrels vs. measurements of fibers with no severe bends.

Abstract: The present invention embraces a multimode optical fiber that includes a central core having an alpha refractive index profile with respect to an outer optical cladding and a depressed trench positioned between the central core and the outer optical cladding. The central core's refractive index at its periphery is the same as the outer cladding's refractive index. Typically, an inner cladding is positioned between the central core and the depressed trench. The optical fiber achieves reduced bending losses without significantly increasing numerical aperture.

Abstract: An embodiment of an apparatus includes an optical fiber for which a complete orthogonal basis of propagating modes at an optical telecommunication frequency includes ones of the propagating modes with different angular momenta. The optical fiber has a tubular optical core and an outer optical cladding in contact with and surrounding the tubular optical core. The tubular optical core has a larger refractive index than the optical cladding. The tubular optical core is configured such that those of the propagating modes whose angular momenta have the lowest magnitude for the propagating modes have substantially the same radial intensity profile.

Abstract: An apparatus includes an optical fiber having a plurality of optical cores therein. Each optical core is located lateral in the optical fiber to the remaining one or more optical cores and is able to support a number of propagating optical modes at telecommunications wavelengths. Each number is less than seventy.

Abstract: The laser light emitting device includes a glass rod having an input end and an output end. The glass rod has a core provided along the central axis thereof and a cladding covering the core. The refractive index of the core on the side of the input end is higher than the refractive index of the cladding. A value given through subtraction of the refractive index of the cladding from the refractive index of the core on the side of the output end is smaller than a value given through subtraction of the refractive index of the cladding from the refractive index of the core on the side of the input end.

Abstract: An optical waveguide, such as an optical fiber, which relies on a mechanism involving scattering in random structures to confine light to a region of the waveguide and allow propagation of electromagnetic radiation along the length of the waveguide includes an optically transmissive body having a length and a cross-section transverse to the length, wherein the optically transmissive body has refractive indices that are cross-sectionally random and substantially invariant along the length direction of the waveguide.

Abstract: An optical waveguide structure containing a plurality of core portions for transmitting light (L), in which adjacent core portions are arranged with substantially parallel central axes, and the optical paths of the light (L) that is transmitted through the adjacent core portions are in opposite directions, wherein each core portion has a tapered section in which the area of the cross-section in a direction substantially perpendicular to the central axis decreases gradually in the direction of the optical path of the light (L). A highly reliable electronic device containing the optical waveguide structure is also provided.

Abstract: A waveguide that includes a first cladding layer, the first cladding layer having an index of refraction, n3; a gradient index layer positioned adjacent the first cladding layer; an assist layer positioned adjacent the gradient index layer, the assist layer having an index of refraction, n2; a core layer positioned adjacent the assist layer, the core layer having an index of refraction, n1; and a second cladding layer, the second cladding layer having an index of refraction, n4, wherein n1 is greater than n2, n3, and n4; and n2 is greater than n3 and n4.

Abstract: Optical illuminators comprise optical fibers having a gradient index core and a cladding selected so that a refractive index difference at a core/cladding interface provides a numerical aperture less than, greater than, or equal to a numerical aperture of the gradient index core. In some examples, a maximum refractive index difference in the gradient index core is substantially the same as, less than, or greater than the refractive index difference at the core/cladding interface. Illuminators based on such fibers are configured to produce optical beams with a laser diode or diode array, and to provide stable, approximately Gaussian optical fluxes at a fiber output surface.

Abstract: An improved multimode fiber optic cable is provided. The improved multimode fiber optic cable includes, but is not limited to, a refractive index profile which is designed to compensate for a radially dependent wavelength distribution of laser launch modes coupled into the multimode fiber optic cable in order to minimize modal dispersion within the multimode fiber optic cable.

Abstract: The invention provides an optical waveguide and a method of making an optical waveguide. The waveguide has a curved section having an asymmetric refractive index profile, in which the refractive index varies asymmetrically across the waveguide cross-section in dependence on the radius of the curved section of the waveguide.

Abstract: An optical waveguide including a first cladding layer; a core layer, including first and second core sections with cladding sections on sides thereof in the in-layer direction; and a second cladding layer. A refractive index distribution in the in-layer direction in the core layer, from the first core section to an adjacent cladding section, has a continuous change and a region with a first peak, a first dip, and a second peak in this order; the first peak at a position of the first core section, the second peak with a maximum value of refractive index smaller than of the first peak, at a position of the cladding section, and a portion, from the first cladding layer to the first core section, corresponded to a refractive index distribution in the layer-stacking direction, discontinuously changing at the boundary between the first cladding layer and first core section.

Abstract: Provided is an inexpensive low-loss optical fiber suitably used in an optical transmission network. An optical fiber includes a core, an optical cladding, and a jacket. The core has a relative refractive index difference between 0.2% and 0.32% and has a refractive index volume between 9%·?m2 and 18%·?m2. The jacket has a relative refractive index difference between 0.03% and 0.20%. Glass constituting the core has a fictive temperature between 1400° C. and 1560° C. Stress remaining in the core is compressive stress. A cutoff wavelength measured on a fiber having a length of 2 m is 1300 nm or more and a cutoff wavelength measured on a fiber having a length of 100 m is 1500 nm or less. An effective area at a wavelength of 1550 nm is 110 ?m2 or more. A attenuation at a wavelength of 1550 nm is 0.19 dB/km or less.

Abstract: According to some embodiments a single mode fiber includes: a germania doped central core region having outer radius r1 and relative refractive index ?1; and a cladding region comprising (i) a first inner cladding region having an outer radius r2>6 microns and relative refractive index ?2 and 0.3?r1/r2?0.85; and (ii) a second inner cladding region having an outer radius r3>9 microns and comprising a minimum relative refractive index ?3, wherein said second inner cladding region has at least one region with a relative refractive index delta that becomes more negative with increasing radius; and (iii) an outer cladding region surrounding the inner cladding region and comprising relative refractive index ?4, wherein ?1>?2>?3, ?3<?4.

Abstract: Various apparatus and methods for reducing inter-core crosstalk in a multicore optical fiber are disclosed. A multicore optical fiber may include a plurality of cores capable of transmitting optical signals, and a cladding surrounding the cores, the cladding having a heterogeneous refractive index such that the optical signals propagate at different velocities in different ones of the cores. A multicore optical fiber may include a first length including cores having heterogeneous modal velocities and a second length, adjacent to the first length, including cores having heterogeneous modal velocities, and the cores in the first length are aligned with cores in the second length having a different modal velocity. Inter-core cross talk in a multicore optical fiber may also be reduced by transmitting optical signals through cores of a multicore optical fiber and pumping light into the cores to create unequal modal velocities in the cores.

Abstract: One embodiment of a single mode optical fiber includes: a graded index central core region having outer radius r1 and relative refractive index ?1; a cladding region comprising (i) a first inner cladding region having an outer radius r2<10 microns and relative refractive index ?2 and 0.65?r1/r2?1; (ii) and a second inner cladding region (i.e., trench) having an outer radius r3>10 microns and comprising a minimum relative refractive index ?3, wherein said second inner cladding region has at least one region with a relative refractive index delta that becomes more negative with increasing radius; and (iii) an outer cladding region surrounding the second inner cladding region and comprising relative refractive index ?4, wherein ?1>?2>?3, ?3<?4.

Abstract: One embodiment of a single mode optical fiber includes: a graded index central core region having outer radius r1 and refractive index ?1; a cladding region comprising (i) a first inner cladding region having an outer radius r2<10 microns and refractive index ?2 and 0.65?r1/r2?1; (ii) and a second inner cladding region having an outer radius r3>10 microns and comprising a minimum refractive index ?3, wherein said second cladding region has at least one region with a refractive index delta that becomes more negative with increasing radius; and (iii) an outer cladding region surrounding the inner cladding region and comprising refractive index ?4, wherein ?1>?2>?3, ?3<?4.

Abstract: An optical fiber comprising: (I) a germania doped central core region having outer radius r1 and (II) a maximum relative refractive index ?1max and a cladding region including (i) a first inner cladding region having an outer radius r2>5 microns and refractive index ?2; (ii) a and a second inner cladding region having an outer radius r3>9 microns and comprising refractive index ?3; and (iii) an outer cladding region surrounding the inner cladding region and comprising refractive index ?4, wherein ?1max>?4, ?2>?3, and wherein 0.01%??4??3?0.09%, said fiber exhibits a 22 m cable cutoff less than or equal to 1260 nm, and 0.25?r1/r2?0.85.

Abstract: A single-mode optical fiber for guiding an optical signal, wherein the core region is capable of guiding an optical signal in a fundamental core mode at an optical signal wavelength. A cladding region is arranged to surround the core region and includes an inner cladding region and an outer cladding region. The inner cladding region includes a background material and a plurality of inner cladding features arranged in the background material, wherein a plurality of the plurality of inner cladding features are of a first type of feature that includes an air hole surrounded by a high-index region comprising a high-index material that is larger than the refractive index of the inner cladding background material.