Abstract: A chemical sensor is provided. The sensor includes at least one lightguiding element having an optical core. The lightguiding element comprises a layer of graphene situated in sufficient proximity to the core to exhibit evanescent wave absorption of optical energy in at least one optical mode guided in the core.

Abstract: An optical active fiber is configured with an asymmetrically-shaped core having at least one long axis and a shortest axis which extends transversely to the long axis. The outmost cladding of the active fiber is configured with a marking indicating the orientation of the short axis. The marking allows for bending the fiber so that the shortest axis extends along and lies in the plane of the bend thereby minimizing distortion of a mode which is guided by the asymmetrically-shaped core as light propagates along the bend.

Abstract: A radiation-resistant optical fiber includes at least one core and at least one first cladding surrounding the core. The core includes a phosphosilicate matrix, the core being rare-earth doped, the rare earth being chosen from erbium, ytterbium, neodymium, thulium or erbium-ytterbium of thulium-holmium codoped and the core is cerium codoped. Also described is a method for radiation-hardening an optical fiber including the core having a phosphosilicate matrix, the core being rare-earth doped, the rare earth being chosen from erbium, ytterbium, neodymium and thulium, or erbium-ytterbium or thulium-holmium codoped, and including a step of cerium codoping the core of the fiber.

Abstract: The present invention provides an optical fiber in which transmission loss is not easily increased when the optical fiber is dipped in water and then dried and also which has a solvent resistant property and a micro-bend resistant property. An optical fiber according to one embodiment of the present invention is an optical fiber in which at least two layers of coating resin coat the circumference of a glass optical fiber. When a Yang's modulus of the first coating layer of the coating resin is defined by PY (MPa) and an elution rate of the coating resin after dipping in 60° C. hot water for 168 hours is defined by E (mass·%), a formula of 1.8?E?8.61×PY+1.40 is satisfied.

Abstract: An optoelectronic transmission module is applied in an optoelectronic connector for data transmission. In the present invention, one flexible circuit board and two hard circuit boards are in electrical connection, among which the first circuit board is electrically connected with an optoelectronic module for connecting with an optical fiber. With this structure, the second and the third circuit boards can transmit or receive data through the optical fiber of the first circuit board. In this manner, this invention can conduct bidirectional data transmission so as to save significantly the consumption of manufacturing cost of the optoelectronic module.

Abstract: A large mode field active optical fiber and manufacture method thereof is provided. The large mode field active optical fiber is formed by drawing a fiber core (1), a quartz glass internal cladding (2), a quartz glass outer cladding (3), and a coating (4). The quartz glass internal cladding (2), the quartz glass outer cladding (3), and the coating (4) are sequentially coated on the outer surface of the fiber core (1). The fiber core (1) is formed by depositing, melting, and shrinking the tetrachlorosilane doped with rare earth ions in a quartz glass tube. The refractive index of the fiber core (1) is a graded refractive index, and the section parameter a thereof is 1???3. The appearance of the quartz glass inner cladding (2) is regular multi-prism shaped.

Abstract: A multicore fiber has a plurality of cores; and a clad which surrounds an outer peripheral surface of each of the cores, and at least one of the cores is spirally arranged such that the core rotates around a center axis of the clad. By arranging the cores in this way, it is possible to prevent crosstalk between specific cores from escalating even when the multicore fiber is disposed in a bent state.

Abstract: A double-clad (DC) multicore (MC) Erbium-doped fiber amplifier (EDFA) for dense-wavelength-division multiplexing (DWDM) is disclosed. The DC-MC-EDFA comprises a length of DC-MC Erbium-doped fiber (EDF) that is core-matched spliced to a MC tapered signal-pump fiber combiner (TFC). For some embodiments, the optical signals are coupled into the DC-MC-EDF by the MC-TFC, and the pump energy is also coupled into the DC-MC-EDF by the MC-TFC. For some embodiments, the optical signals are also transmitted out of the DC-MC-EDF through the MC-TFC.

Abstract: An optical fiber includes multiple cores and a cladding. At least one of the multiple cores forms an optical waveguide and has an elongated cross-section with a narrower dimension in a fast-axis direction and a wider dimension in a slow-axis direction. The cladding surrounds the multiple cores and has a refractive index that differs from at least one refractive index of the multiple cores. The multiple cores could be stacked such that a first of the multiple cores is located at least partially over a second of the multiple cores in the fast-axis direction. The optical fiber could include an additional core within the cladding and having a substantially circular cross-section. The cores could be used to transport a high-power laser beam, an illumination laser beam, and an alignment laser beam. The optical fiber could have a length of at least two meters.

Abstract: Polarization maintaining optical fibers and methods for making the same are disclosed herein. According to one embodiment, a polarization maintaining optical fiber includes a cladding portion and a core portion disposed in the cladding portion. The core portion includes a first core region having a first coefficient of thermal expansion CTE1 and a second core region having a second coefficient of thermal expansion CTE2. The first coefficient of thermal expansion CTE1 is not equal to the second coefficient of thermal expansion CTE2. At least one of the first core region and the second core region is non-circular symmetric with respect to a centerline of the polarization maintaining optical fiber.

Abstract: An optical fiber suitable for high-capacity transmission having a large effective core area, a low bending loss, and capable of single mode operation at 1550 nm is provided. The optical fiber 10 has an effective core area ?175 ?m2 at 1550 nm, a bending loss ?10 dB/m at a bending diameter of 20 mm at 1550 nm, and a cut-off wavelength ?c?1550 nm. The optical fiber has a first core 11 at the center, which has a refractive index higher than that of the cladding 13; and a second core 12 around the first core 11, which has a refractive index lower than that of the cladding 13; a primary medium portion; and secondary medium portions, which have a refractive index lower than that of the primary medium portion and the secondary medium portions have a plurality of first secondary medium portions 15 around the first core 11 and a plurality of second secondary medium portions 16 around the first core 11 and outside of the first secondary medium portions 15.

Abstract: An optical fiber comprising a first core, a second core, a third core, and a cladding, wherein with a refractive index of the cladding as a reference, ?1 is a maximum value of a relative refractive index difference of the first core, ?2 is a maximum value of a relative refractive index difference of the second core, ?3 is a minimum value of a relative refractive index difference of the third core, “a” is a half-value radial width for the relative refractive index difference (?1??2) of the first core, “b” is a radius of a second core/third core boundary, and “c” is a radius of a third core/cladding boundary, the expressions 0.30%??1?0.45%, ?0.05%??2?0.05%, ?0.6%??3??0.3%, 2.85?b/a, 10 ?m?b?15 ?m, and 3 ?m?c?b?5.5 ?m are satisfied, and transmission loss 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 0.2 dB/turn.

Abstract: A multimode optical fiber includes: (i) a graded index glass core having a radius R1 in the range of 20 microns to 50 microns, a maximum relative refractive index ?1MAX in the range between 0.5% and 3%; a graded index having a profile with (a) by an alpha (?) parameter wherein 1.9???2.2, and (b) a deviation from the alpha profile in at least one region of the core, such that the difference in the refractive index delta of the core from that determined by the core alpha value, at the radius R1 is less than 0.001, and (ii) a cladding surrounding and in contact with the core, wherein the fiber has an bandwidth greater than 5000 MHz-km at a wavelength ? where ??800 nm.

Abstract: Provided is a method of producing a preform 10P for a coupled multi-core fiber including: an arranging process P1 for arranging a plurality of core glass bodies 11R and a clad glass body 12R in such a way that the plurality of core glass bodies 11R are surrounded by the clad glass body 12R; and a collapsing process P2 for collapsing a gap between the core glass bodies 11R and the clad glass body 12R, wherein the respective core glass bodies 11R have outer regions 16 having a predetermined thickness from the periphery surfaces and made of silica glass undoped with germanium, and the clad glass body 12R is made of silica glass having a refractive index lower than a refractive index of the outer regions of the core glass bodies 11R.

Abstract: A multicore fiber includes a plurality of core elements; and a clad surrounding an outer periphery surface of each of the core elements, and each of the core elements includes a core, a first clad surrounding the outer periphery surface of the core and a second clad surrounding an outer periphery surface of the first clad, and when a refractive index of the core is n1, a refractive index of the first clad is n2, a refractive index of the second clad is n3 and a refractive index of the clad is n4, all of n1>n2>n3, n1>n4 and n3<n4 are satisfied.

Abstract: A multicore fiber 1 includes a plurality of cores 3 disposed at predetermined intervals and surrounded by a cladding 5. The multicore fiber 1 also includes a marker 7 formed apart from the cores 3. The refractive index of the marker 7 is different from those of the cores 3 and the cladding 5. For example, the marker 7 may be made of a material having lower refractive index than that of the cladding 5. In this case, for example, the cores 3 may be made of germanium-doped quartz. The cladding 5 may be made of pure quartz. The marker 7 may be made of fluorine-doped quartz. Further, the marker 7 may be an empty hole.

Abstract: The disclosure is directed to an all glass method that frustrates the internal reflection on the outside diameter of an optical fiber's glass cladding thus allowing the light to be directed to a light absorbing material/ medium and allowing the desired light in the core of the fiber to be preserved with no loss. The frustration is achieved by having at least one glass frustrater in glass-to-glass contact with the outermost cladding layer of the optical fiber. The glass frustrater is made of a glass that has a glass transition point lower that both the core and cladding glasses of the fiber. Chalcogenide and phosphate glasses are among the glasses suitable for this application.

Abstract: An optical fiber includes: a core including a photosensitive material disposed therein, the core having a first index of refraction; a depressed cladding surrounding the core and having a second index of refraction that is lower than the first index of refraction; and an outer cladding surrounding the depressed cladding and having a third index of refraction that is higher than the depressed cladding.

Abstract: A multicore fiber includes a cladding and a plurality of core elements which is provided in the cladding and includes a core, an inner cladding layer that surrounds the core, and a low-refractive index layer that surrounds the inner cladding layer and has a lower average refractive index than the cladding and the inner cladding layer. The plurality of core elements is arranged such that a specific core element is surrounded by three or more core elements, and a low-refractive index layer of a partial core element of the plurality of core elements is configured to have larger light confinement loss in the core than low-refractive index layers of the other partial core elements.

Abstract: A polarization-maintaining optical fiber of the present invention includes a core, a pair of stress-applying parts provided on both sides of the core, and a cladding surrounding the core and the stress-applying parts, and is used in a wavelength range of 400 to 680 nm. The diameter of the cladding is 125 ?m, the diameter of the stress-applying part is 33 to 37 ?m, a distance between the pair of stress-applying parts is 8.6 to 15.4 ?m, a relative refractive index difference between the core and the cladding is 0.35 to 0.45%, and a cut-off wavelength is less than or equal to 400 nm.

Abstract: To provide an X-ray waveguide which: shows a small propagation loss of an X-ray; has a waveguide mode with its phase controlled; does not deteriorate owing to oxidation; and can be easily produced, an X-ray waveguide, including: a core for guiding an X-ray in such a wavelength band that a real part of the refractive index of a material is 1 or less; and a cladding for confining the X-ray in the core, in which: the core has a one-dimensional periodic structure containing multiple materials having different real parts of the refractive index; the multiple materials include one of an organic material, a gas, and a vacuum, and an inorganic material; and the core and the cladding are formed so that the critical angle for total reflection at an interface between the core and the cladding is larger than a Bragg angle resulting from a periodicity of the one-dimensional periodic structure, is realized.

Abstract: A multi-core optical fiber may include a cladding with a cross section having a central region and an outside diameter. Multiple transmission cores are arranged symmetrically within the central region of the cladding, extending parallel to a central axis of the multi-core optical fiber. Multiple alignment cores are arranged within the cladding, extending parallel to the central axis of the multi-core optical fiber and near the outside diameter of the cladding so that each of the multiple alignment cores are visible through a side view of the cladding. Ends of similarly configured multi-core optical fibers may be mated and aligned. Alignment cores of a first multi-core optical fiber may be aligned with alignment cores of a second multi-core optical fiber using a side view of the mating interface. Aligning the alignment cores causes multiple transmission cores with the multi-core optical fibers to also align.

Abstract: An optical fiber which includes a core region embedded within a cladding. The core region of the optical fiber further comprises multiple sections, each doped with rare earth ions.

Abstract: An optical component according to an embodiment of the present invention is constructed of a plurality of MCFs each having the same core constellation structure and among the plurality of MCFs, a maximum deviation of a core pitch between neighboring cores and a maximum deviation of a spot size of a fundamental mode at an operating wavelength satisfy a specific relation, thereby suppressing structural variation so as to keep a splice loss not more than 1 dB.

Abstract: The invention relates to a fiber structure (700), which has one or more refractive index disturbances (750, 760) outside a fiber core (710) for discriminating one or more high order modes in the fiber structure. The invention also relates to a method for discriminating one or more high order modes, an arrangement having the high order modes discriminating fiber structure, and a device having the high order mode discriminating fiber structure.

Abstract: The present invention relates to an optical fiber and an optical cable which can be used for a long term even under environments in which an oil content migrates into them, and the optical fiber has a glass fiber extending along a predetermined axis, and a coating. The coating is composed of a plurality of layers each of which is comprised of an ultraviolet curable resin or a thermosetting resin, and swelling rates of the respective coating layers are set so that they increase from an outer peripheral surface of the glass fiber to an outer peripheral surface of the cable jacket.

Abstract: A multicore optical fiber includes a plurality of core regions disposed within a common cladding region. Each of the plurality of core regions is configured, in combination with the common cladding region, to propagate light along a longitudinal axis of the fiber. At least two core regions are configured to inhibit resonant coupling of propagated light therebetween within a selected region of operation. At least one segment of the fiber includes a twist that is configured such that when the twisted segment is subjected to a bend having a selected radius, the twist creates a controlled change in the amount of crosstalk between the at least two core regions, compared with the amount of crosstalk between the at least two core regions when a bend having the selected radius is introduced into a non-twisted segment of the fiber.

Abstract: A dispersion compensation fiber comprises a fiber core and cladding. The fiber core is a core layer mainly doped with germanium and having a positive relative refractive index difference. The cladding covering the fiber core comprises a trench cladding mainly doped with fluorine, an annular cladding mainly doped with germanium, a matching cladding mainly doped with fluorine, and an outermost mechanical cladding in order. Relative refractive index differences of the fiber core and the claddings are respectively: ?1% being 1.55% to 2.20%, ?2% being ?0.55% to ?0.30%, ?3% being 0.40% to 0.65%, ?4% being ?0.20% to ?0.01%, and ?5% being 0. Radius ranges, from R1 to R5, of the fiber core and the claddings are respectively: R1 being 1.4 to 1.7 ?m, R2 being 4.1 to 4.8 ?m, R3 being 6.7 to 8.8 ?m, R4 being 10 to 17 ?m, and R5 being 38 to 63 ?m.

Abstract: A fan-in/fan-out device includes a plurality of single-core fibers which are connected to a plurality of first cores of a multicore fiber and which include an elongated portion extending in a longitudinal direction so as to reduce a diameter and being connected to a first end portion of the multicore fiber at a second end portion in an extending direction of the elongated portion, where a refractive index distribution of each of the single-core fibers has a single peak, a relative refractive index difference of a second core with respect to a second cladding in each of the single-core fibers is 0.8% or more; and a second mode field diameter of the second end portion of the elongated portion is greater than a first mode field diameter of the first end portion of the multicore fiber.

Abstract: In one embodiment, an apparatus may include a first capillary component. A second capillary component may be disposed outside of the first capillary component and may have an inner surface, wherein a portion of the inner surface may be heat-fused to an outer surface of the first capillary component. The apparatus may also include a portion of an optical fiber disposed inside of the first capillary component and the portion of the optical fiber can have an outer surface. A portion of the outer surface of the optical fiber may be heat-fused to an inner surface of the first capillary component. The optical fiber may have a distal surface configured to reflect electromagnetic radiation propagated along a longitudinal axis of a distal end portion of the optical fiber in a lateral direction through the inner surface of the first capillary component and the inner surface of the second capillary component.

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.

Abstract: An optical fiber according to an embodiment of the present invention is provided with a center core, a side core, and a cladding. The center core includes a ring part where a relative index difference varies discontinuously, in its peripheral region, and when a is a radius from a core center to an outside of the ring part and c is a radius to a position where the relative index difference is maximum in the side core, an index profile is realized in a shape where c/a is in the range of 2.25 to 2.50, so as to enable setting of a dispersion value, a cable cutoff wavelength, a bending loss in the diameter of 20 mm, and an effective area in desired ranges.

Abstract: Various embodiments described herein comprise a laser and/or an amplifier system including a doped gain fiber having ytterbium ions in a phosphosilicate glass. Various embodiments described herein increase pump absorption to at least about 1000 dB/m-9000 dB/m. The use of these gain fibers provide for increased peak-powers and/or pulse energies. The various embodiments of the doped gain fiber having ytterbium ions in a phosphosilicate glass exhibit reduced photo-darkening levels compared to photo-darkening levels obtainable with equivalent doping levels of an ytterbium doped silica fiber.

Abstract: An optical fiber coupler connects transmission multicore optical fiber (TMCF) with an amplifier multicore optical fiber (AMCF) and a plurality of optical pump fibers. The coupler includes a plurality of signal cores extending between a multicore input endface and a coupler output endface, and a plurality of pump cores extending between a pump input and the coupler output endface. The multicore input endface is connectable to the TMCF, and the pump input is connectable to the optical pump fibers. Each pump core is paired with a corresponding signal core to form a core pair that is adiabatically tapered such that signal light carried by the signal core is combined with pump light carried by the pump core. The coupler output endface is connectable to the AMCF such that the combined light output of each core pair is provided as an input to a respective AMCF core.

Abstract: A multi-core fiber includes an even number of six or more of cores and a clad that surrounds the outer circumferential surfaces of the cores. The cores are formed of two types of cores and in which an effective refractive index difference in a fundamental mode is 0.002 or less in a predetermined range or more that the effective refractive index difference in the fundamental mode is varied according to a core pitch. Two types of the cores are alternately and annularly disposed at regular spacings. A difference in the mode field diameter of light propagating through the cores is 1 ?m or less.

Abstract: A depressed graded-index multimode optical fiber includes a central core, an inner depressed cladding, a depressed trench, an outer depressed cladding, and an outer cladding. The central core has an alpha-index profile. The depressed claddings limit the impact of leaky modes on optical-fiber performance characteristics (e.g., bandwidth, core size, and/or numerical aperture).

Abstract: A multimode optical fiber includes a central core having a radius (r1) and an alpha-index profile. The multimode optical fiber further includes a depressed trench, which surrounds the central core, that has a width (wt) and a refractive index difference (?nt) with an outer optical cladding. Typically, the central core's diameter is between about 47 and 53 microns, and the depressed trench's width (wt) is between 0.5 micron and 2 microns. The depressed trench's refractive index difference (?nt) with the outer optical cladding is typically between ?4×10?3 and ?1×10?3.

Abstract: The present invention relates to a multicore optical fiber having a structure for suppressing core-to-core crosstalk. The multicore optical fiber (100A) comprises a plurality of cores extending along a predetermined axis while being arranged like a hexagonal lattice on a cross section perpendicular to the axis and a cladding region (120) integrally surrounding the plurality of cores. All of core portions, each constituting at least a part of the associated one of the plurality of cores, have substantially the same structure.

Abstract: The present invention relates to an optical fiber cable incorporating a multi-core fiber provided with a plurality of cores and a cladding region. The optical fiber cable has a jacket covering the multi-core fiber. The multi-core fiber is arranged so that a hold wrap holds the cores in a state in which they are provided with a bend of not more than a fixed radius of curvature, in order to reduce crosstalk between the cores.

Abstract: Holey fibers provide optical propagation. In various embodiments, a large core holey fiber comprises a cladding region formed by large holes arranged in few layers. The number of layers or rows of holes about the large core can be used to coarse tune the leakage losses of the fundamental and higher modes of a signal, thereby allowing the non-fundamental modes to be substantially eliminated by leakage over a given length of fiber. Fine tuning of leakage losses can be performed by adjusting the hole dimension and/or spacing to yield a desired operation with a desired leakage loss of the fundamental mode. Resulting holey fibers have a large hole dimension and spacing, and thus a large core, when compared to traditional fibers and conventional fibers that propagate a single mode. Other loss mechanisms, such as bend loss and modal spacing can be utilized for selected modes of operation of holey fibers.

Abstract: An optical fiber having both low bend loss. The fiber has a central core region having refractive index ?1, an inner cladding region having an outer radius r2>17 microns and refractive index ?2 and a second cladding region surrounding the inner cladding region having refractive index ?3. The fiber profile segments may be arranged so that ?1>?3>?2. The fiber may exhibit a profile volume, V2 of the inner cladding region, calculated between r1 and r2, is at least 30% ?micron2.

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: Optical fibers are provided for modal discrimination which include a central core and a cladding disposed about the central core. The central core has a non-circular and non-elliptical cross-section, and it is rotated about a central axis of the optical fiber along the length of the optical fiber at a selected pitch resulting in the capability of a fundamental mode beam output for large core sizes. An optical system includes a seed optical source configured to provide a seed beam and an optical amplifier configured to receive and amplify the seed beam. The optical amplifier also includes an active optical fiber having a large mode area non-circular and non-elliptical core rotated about a central axis of said active optical fiber to provide modal discrimination and fundamental mode output.

Abstract: A high-powered double cladding (DC) pumped Ytterbium-free L-band Erbium doped fiber amplifier (EDFA) for dense-wavelength-division multiplexing (DWDM) is disclosed. The DC pumped Ytterbium-free L-band EDFA comprises a length of DC Erbium-doped fiber (EDF) that has a low-index, large-diameter core. For some embodiments, the DC-EDF also comprises a trench that is located radially exterior to the cladding, thereby increasing cladding absorption while still effectively maintaining single-mode behavior.

Abstract: An optical fiber comprising: (i) a core having a refractive index profile; (ii) an annular cladding surrounding the core; (iii) a primary coating contacting and surrounding the cladding, the primary coating having an in situ modulus of less than 0.35 MPa and an in situ glass transition temperature of less than ?35° C.; and (iv) a secondary coating surrounding the primary coating, the secondary coating having an in situ modulus of greater than 1200 MPa; wherein the refractive index profile of said core is constructed to provide an LP11 theoretical cutoff wavelength greater than 2.0 ?m and an effective area greater than 110 microns2 at 1550 nm.

Abstract: An optical device comprising a multi-core optical fiber coupler. The multi-core optical fiber coupler includes a substrate having a planar surface and turning mirrors located along the planar surface, each of the turning mirrors having a reflective surface oriented to change a direction of light between a direction that is parallel to the planar surface and a direction that is substantially non-parallel to the planar surface. The turning mirrors form a lateral pattern along the planar surface, the lateral pattern being configured to approximately match a pattern of optical cores in a multi-core optical fiber whose end segment faces the pattern and is positioned substantially normal to the planar surface of the substrate.

Abstract: An easily producible optical fiber preform which is drawn to an optical fiber having a core containing a sufficient concentration of alkali metal is provided. An optical fiber preform 10 is composed of silica-based glass and includes a core portion 20 and a cladding portion 30. The core portion 20 includes a first core portion 21 including a central axis and a second core portion 22 disposed on the perimeter of the first core portion 21. The cladding portion 30 includes a first cladding portion 31 disposed on the perimeter of the second core portion 22 and a second cladding portion 32 disposed on the perimeter of the first cladding portion 31. The core portion 20 contains an alkali metal at an average concentration of 5 atomic ppm or more. The concentration of the OH group in the perimeter portion of the first cladding portion 31 is 200 mol ppm or more.

Abstract: Various embodiments of optical fiber designs and fabrication processes for ultra small core fibers (USCF) are disclosed. In some embodiments, the USCF includes a core that is at least partially surrounded by a region comprising first features. The USCF further includes a second region at least partially surrounding the first region. The second region includes second features. In an embodiment, the first features are smaller than the second features, and the second features have a filling fraction greater than about 90 percent. The first features and/or the second features may include air holes. Embodiments of the USCF may provide dispersion tailoring. Embodiments of the USCF may be used with nonlinear optical devices configured to provide, for example, a frequency comb or a supercontinuum.

Abstract: Methods and apparatus are provided for transmitting light along multiple pathways using a multi-core optical device. One example apparatus generally includes a plurality of large diameter optical waveguides, each having a core and a cladding, and a body having a plurality of bores with the optical waveguides disposed therein, wherein at least a portion of the cladding of each of the optical waveguides is fused with the body, such that the apparatus is a monolithic structure. Such an apparatus provides for a cost- and space-efficient technique for feedthrough of multiple optical waveguides. Also, the body may have a large outer diameter which can be shaped into features of interest, such as connection alignment or feedthrough sealing features. For some embodiments, at least some of the cores may have different structural parameters (e.g., size and/or shape).

Abstract: Apparatus and method are provided for transmitting at least one electro-magnetic radiation is provided. In particular, at least one optical fiber having at least one end extending along a first axis may be provided. Further, a light transmissive optical arrangement may be provided in optical cooperation with the optical fiber. The optical arrangement may have a first surface having a portion that is perpendicular to a second axis, and a second surface which includes a curved portion. The first axis can be provided at a particular angle that is more than 0° and less than 90° with respect to the second axis.