OFS FITEL, LLC Patent applications |
Patent application number | Title | Published |
20160139337 | Dual-Ended Optical Fiber Pathway - In an optical fiber turnaround, first and second optical fiber cores are configured to transmit light bidirectionally along a transmission axis between proximal and distal ends of the first and second optical fiber cores. A reflector component is positioned at the distal ends of the first and second optical fiber cores. The first core, second core, and reflector component are configured to provide a bidirectional routing path, wherein light energy travels from the proximal end of one of the first and second cores towards the reflector component, and travels back from the reflector component along the other of the first and second cores. | 05-19-2016 |
20160033720 | POLARIZATION-MAINTAINING (PM) DOUBLE-CLAD (DC) OPTICAL FIBER - A double-clad (DC) polarization-maintaining (PM) optical fiber comprises a core, an inner cladding, an outer cladding, and stress rods. The core has a core refractive index (n | 02-04-2016 |
20160033100 | Light-Emitting Diode Input For Hybrid Solar Lighting Systems - A hybrid lighting system is disclosed in which light emitting diodes (LEDs) provide input light When illumination with solar light is unavailable. Light from LEDs are propagated through an optical fiber, which delivers the light to a point of illumination. The disclosed system reduces the amount of electricity and electric conduit for light in areas using hybrid lighting systems. | 02-04-2016 |
20160018616 | DROP CABLE ASSEMBLY - Drop cable assemblies suitable for an optical fiber distribution system are disclosed. For some embodiments, the drop cable assembly splits an input optical fiber to a plurality of optical fibers and provides optical connection to designated premises. For other embodiments, the drop cable assembly receives multi-fiber optical connection and provides the optical connections to designated premises. | 01-21-2016 |
20160018615 | PLUG-AND-PLAY OPTICAL FIBER DISTRIBUTION SYSTEM - An optical fiber distribution system is disclosed. The distribution system has a cable combiner and a splitter housing. The distribution system is a plug-and-play system. | 01-21-2016 |
20160018612 | SYSTEMS AND METHODS FOR CABLE DISTRIBUTION - A fiber-optic system is disclosed in which a self-supporting cable comprises self-supporting break-out sub-cables, which provide fiber-optic connectivity to customer premises. | 01-21-2016 |
20160004025 | OPTICAL FIBER SEISMIC SENSING CABLE - Described is an improved optical fiber cable specially adapted for seismic sensing. Compared with standard optical fiber cable, this improved optical fiber cable is reduced in size, lighter, and more flexible. These characteristics make the optical fiber cable more robust for reusable applications. Due to modifications in the design of the optical fibers, the size and weight of the seismic sensing cable may be substantially reduced. That allows longer lengths of seismic sensing cable, and more seismic sensor boxes, to be reeled on a given sized reel, and makes deployment of the seismic sensing cable faster, easier, and less expensive. A preferred cable design for reaching these objectives comprises multiple optical fibers, of a design just described, encased in a dual-layer optical fiber buffer encasement of acrylate resin. | 01-07-2016 |
20160003976 | Statistical Prediction Functions For Natural Chaotic Systems And Computer Models Thereof - A method and apparatus for precipitation prediction is provided. In exemplary embodiments, the method may comprise, at a server having one or more processors and memory storing one or more programs for execution by the one or more processors: decomposing climate model attractors; receiving ground data in a region from a client as well as global data; reweighting and reordering the relative importance of the climate model attractors based on a rank and incorporating the ground data; reassembling a selected group of data including the ground data, thereby adding information to the climate model; and generating a prediction of regional weather based on the reassembled selected group of data. | 01-07-2016 |
20150364897 | Discrete Raman Amplifier - A discrete Raman amplifier comprises a Raman gain fiber, an input port into the Raman gain fiber for receiving optical signals to be Raman amplified, and an output port out of the Raman gain fiber for emitting Raman-amplified optical signals. A pump light input provides pump light to the Raman gain fiber at a plurality of wavelengths so as to provide Raman amplification over the selected signal wavelength range. Within both the pump light wavelength range and the selected signal wavelength range, the Raman gain fiber has only positive chromatic dispersion, and the Raman gain fiber has a moderate effective area. | 12-17-2015 |
20150362670 | BEND COMPENSATION IN TELECOMMUNICATIONS OPTICAL FIBERS - Optical fiber profiles are shown in which the optical fiber has a large mode area, but is nevertheless sufficiently bend-insensitivity to comply with technical specifications for telecommunication optical fibers. The optical fibers meet two bend-loss conditions. First, they meet tight bend conditions, which reflects macro-bending due to coiling or bending of the optical fiber. Second, these optical fibers meet cable bend conditions, which reflect macro-bending conditions that are introduced as a result of cabling. By satisfying the tight bend-loss condition and then adjusting for the cable bend-loss condition, the optical fiber permits larger effective areas than normally achievable with only bend-compensation designs. | 12-17-2015 |
20150340830 | MODE CONVERTER FOR HIGH POWER, HIGHER-ORDER MODE OPTICAL FIBER AMPLIFIERS - A mode converter for use with a higher-order mode (HOM)-based fiber amplifiers takes the form of axicon-based configuration that is able to convert high power (tens of mW and higher) optical signals propagating in higher-order mode form into a diffraction-limited beam without experiencing the nonlinear effects (such as self-phase modulation) that are found when using a long-period grating (LPG) to create a diffraction-limited beam by performing mode conversion. The axicon may comprise a bulk optic device, a fiber-based device, or a GRIN-based configuration (where the refractive index profile of the GRIN element is formed to create a diffraction-limited signal). | 11-26-2015 |
20150316716 | OPTICAL FIBER WITH DISTRIBUTED BEND COMPENSATED FILTERING - An optical fiber includes a core region having a longitudinal axis. At least a portion of the core region has a substantially helical shape about a helical axis. The longitudinal axis may be substantially tangential to a helical bend in the optical fiber. A cladding region surrounds the core region. The core region and cladding region may be configured to support and guide the propagation of signal light in a fundamental transverse mode in the core region in the direction of the longitudinal axis. The fiber has a bend-induced gradient in its equivalent index of refraction over the portion of the core region. The fiber has a bend-induced equivalent index of refraction. At least a portion of cladding region has a graded refractive index opposite that of the bend-induced gradient. The cladding region may be configured to have a substantially flat equivalent index in response to a helical bend of the optical fiber. | 11-05-2015 |
20150301291 | STRUCTURES AND TECHNIQUES FOR ALIGNING A MULTICORE FIBER IN A FERRULE OR PRODUCTION JIG - An alignment block for aligning a multicore fiber has a body with a front face and a rear face, and includes a capillary extending between a front opening at the first face and a rear opening at the rear face. The capillary has an inner circumference that includes an alignment surface corresponding to the multicore fiber alignment surface. The front opening is shaped to fit closely around the multicore fiber so as to prevent non-longitudinal movement of the multicore fiber relative to the alignment block body. The rear opening is shaped to fit around the multicore fiber so as to allow a selected amount of non-longitudinal movement of the multicore fiber relative to the alignment block body. The capillary provides tapered transition between the rear opening and the front opening. Movement of the multicore fiber along the capillary causes the multicore fiber alignment surface to be urged against the capillary alignment surface so as to align the multicore fiber cores relative to the alignment block body. | 10-22-2015 |
20150295382 | Arrayed Optical Fiber Amplifier Using Ribbonized Erbium-Doped Fiber - Systems and methods for reducing cost and amplifier module size are disclosed. One system comprises an arrayed optical fiber amplifier that uses a ribbonized fiber that permits reduction of amplifier module size and also reduction in the cost of manufacturing that are not readily achievable in other currently-available systems. | 10-15-2015 |
20150293300 | Single-Mode, Bend-Compensated, Large-Mode-Area Optical Fibers Designed To Accomodate Simplified Fabrication And Tighter Bends - Described is a general strategy of bend-compensated, single-mode LMA fibers extended into a regime with higher total index contrast and where a larger gradient is used to cancel the perturbation of a tighter anticipated bend. | 10-15-2015 |
20150285993 | Fiber Bragg Gratings In Carbon-Coated Optical Fibers And Techniques For Making Same - A technique is described for fabricating one or more optical devices in a carbon-coated optical fiber. A photosensitive optical fiber is provided having a hermetic carbon coating. Further provided is a laser having a beam output that is configured to inscribe one or more refractive index modulations into the optical fiber through the hermetic carbon layer while leaving the hermetic carbon layer intact. The laser is used to inscribe one or more optical devices into the optical fiber through the hermetic carbon layer. | 10-08-2015 |
20150277049 | OPTICAL DELAY LINE FORMED AS SURFACE NANOSCALE AXIAL PHOTONIC DEVICE - A surface nanoscale axial photonic (SNAP) device in the form of an optical bottle resonator is configured to exhibit a semi-parabolic profile (in terms of a change in radius along the longitudinal direction of the fiber). It has been found that this semi-parabolic profile provides the ability to create the dispersionless delay of optical pulses, where “dispersionless” in this case is considered to mean that the pulse retains its same shape with minimal distortions as it passes back and forth within the bottle resonator (i.e., minimal pulse-broadening). Delays on the order of several nanoseconds have been created within these semi-parabolic-shaped SNAP bottle resonators of about 3 mm in length (as compared with prior art microresonator devices' ability to create delays no greater that 1 ns, at best). | 10-01-2015 |
20150260763 | FEW-MODED FIBER FOR SENSING CURRENT - A few-moded fiber is doped such that spatial modes of a signal exhibit different magnetic-field-dependent effects. Based on these magnetic-field-dependent effects, one can determine the electric current that induced a magnetic field that caused these effects. | 09-17-2015 |
20150253499 | Broadband Multi-Mode Optical Fibers With Flat-Zone In Dopant Concentration Profile - Described is a design approach to fabricating broadband graded-index multimode fibers where the concentration profile of at least one dopant in the core region includes at least one flat-zone. Designs for use in CWDM applications are also disclosed. | 09-10-2015 |
20150253498 | Framework For the Design of Optimum and Near-Optimum Broadband Multi-Mode Optical Fibers - Described is a technique for optimizing the design and manufacture of broadband MMFs. MMFs for use in CWDM applications are specifically described. | 09-10-2015 |
20150153529 | OPTICAL FIBER CABLES WITH POLYETHYLENE BINDER - An optical fiber cable includes a bundle of a plurality of loose tubes held by a polyethylene binder. The polyethylene binder softens or melts when a hot cable sheath is applied during the cable manufacturing process. This prevents the polyethylene binder to cut into the loose tubes to cause indentations. Therefore, the resulting optical fiber cable is substantially free from indentations. | 06-04-2015 |
20150147025 | METHOD OF OPTIMIZING MULTICORE OPTICAL FIBER AND DEVICES UTILIZING SAME - A method of designing multicore optical fibers is provided. A geometry for the core arrangement is selected. At least one of i) core width, ii) core position with respect to other cores, or iii) orientation with respect to incoming, outgoing, or at least partially traversing radiation such as an inscription beam are optimized. A design space is created in which no core shadows or blocks any other core with respect to incoming, outgoing, or at least partially traversing radiation. Optimization generally includes tracing tangents of core widths against an orthogonal axis and ensuring no overlap of space between said tangents on said axis. For twisted fiber, optimization also includes optimizing effective length and twist rate of the fiber. Devices entailing such fibers, such as multicore pump coupler and multicore fiber distributed feedback laser, are also contemplated. | 05-28-2015 |
20150077837 | Gain-Equalized Few-Mode Fiber Amplifier - A few-mode rare-earth-doped amplifier fiber has equalized gain for the supported signal transmission modes. The fiber has a raised-index core surrounded by a lower-index cladding region. The core has a radius a | 03-19-2015 |
20150016792 | HIGHLY NONLINEAR OPTICAL FIBER WITH IMPORVED SBS THRESHOLD AND MODERATE ATTENUATION - A highly nonlinear optical fiber having an improved stimulated Brillouin scattering threshold is provided. The fiber includes a central core region made substantially from silica doped with aluminum, a trench region surrounding the central core region, and a silica cladding surrounding the trench region. The refractive index profile of the fiber is optimized. A refractive index difference of the central core region relative to the cladding (Δn+) is less than 26×10 | 01-15-2015 |
20140376576 | HIGH-FIDELITY, HIGH-ENERGY ULTRASHORT PULSES FROM A NET NORMAL-DISPERSION YB-FIBER LASER WITH AN ANOMALOUS DISPERSION HIGHER-ORDER-MODE FIBER - Embodiments of the present invention generally relate to high energy, ultrashort pulses from a net normal dispersion ytterbium fiber laser with an anomalous dispersion higher-order mode fiber. More specifically, embodiments of the present invention relate to a fiber oscillator with all-fiber dispersion compensation delivering pulse parameters comparable to solid-state oscillators having good compensation of higher order dispersion and intracavity nonlinearities. In one embodiment of the present invention, an oscillator comprises a length of single mode fiber and a length of higher-order mode fiber, where the group delay dispersion (GDD) of the higher-order mode fiber is chosen to match 50% or more of the GDD of the single mode fiber; wherein a third-order dispersion of the oscillator matches a nonlinear phase buildup in a cavity of the oscillator, and the nonlinear phase buildup is dependent upon the pulse energy of the oscillator. | 12-25-2014 |
20140334788 | Bend Compensated Filter Fiber - An optical fiber includes a core region having a longitudinal axis. A cladding region surrounds the core region. The core region and cladding region are configured to support and guide the propagation of signal light in a fundamental transverse mode in the core region in the directions of the axis. The fiber has a bend-induced gradient of its equivalent index of refraction indicative of a loss in guidance of the mode. At least a portion of cladding region has a graded index of refraction opposite the bend-induced gradient. The cladding region is configured to have a substantially flat equivalent index in response to a bend of the optical fiber. | 11-13-2014 |
20140314372 | SUPPRESSION OF STIMULATED BRILLOUIN SCATTERING IN HIGHER-ORDER- MODE OPTICAL FIBER AMPLIFIERS - An HOM-based optical fiber amplifier is selectively doped within its core region to minimize the presence of dopants in those portions of the core where the unwanted lower-order modes (particularly, the fundamental mode) of the signal reside. The reduction (elimination) of the gain medium from these portions of the core minimizes (perhaps to the point of elimination) limits the amount of amplification impressed upon the backward-propagating Stokes wave. This minimization of amplification will, in turn, lead to a reduction in the growth of the Stokes power that is generated by the Brillouin gain, which results in increasing the amount of power present in the desired, forward-propagating HOM amplified optical signal output. | 10-23-2014 |
20140312014 | Compensation Of Fiber Lensing Effect During Grating Fabrication In Multicore Fiber - An arrangement and method that compensates for variation in grating strength associated with forming multiple gratings in multicore fiber is proposed where the writing efficiency of the beam(s) used to form the gratings is controlled to compensate for fiber lensing effects. In one case, a spacing between the multicore optical fiber and the beam source is controlled such that the writing efficiency (which decreases as a function of the space between the source and the fiber) compensates (at least in part) for the increased beam intensity attributed to the lensing effect of the fiber itself. The width of beam itself may also be controlled to modify the writing efficiency. | 10-23-2014 |
20140307304 | MULTI-CORE ERBIUM-DOPED FIBER AMPLIFIER - 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. | 10-16-2014 |
20140307251 | LIVE OPTICAL FIBER IDENTIFIER TOOL - A live fiber identifier tool includes a head portion having a slot. A cable containing a pair of optical fibers can be inserted in the slot and forced to bend inside the head portion when a trigger is operated. Any light signal in a given fiber partially leaks from the fiber and exits the cable bend. Two photo detectors are located so that one of the detectors receives more light from the cable bend than the other detector depending on the signal direction in the given fiber. Processing components coupled to the detectors and the indicator define a threshold factor that corresponds to a determined difference between the outputs of the detectors. If the difference between the detector outputs does not exceed the threshold factor, an indicator on the tool reports that light signals are traveling in the pair of optical fibers in opposite directions along the cable. | 10-16-2014 |
20140307250 | LIGHT COVER OR HOOD FOR LIVE OPTICAL FIBER IDENTIFIER TOOL - A light hood for a fiber identifier tool that includes a head portion having interior photo detectors, a slot for receiving an optical fiber to be tested, and a clamp mechanism for urging the fiber to bend in the vicinity of the photo detectors when the mechanism is operated. The hood has a generally T-shaped body that defines a lower hood portion arranged to engage the clamp mechanism and operate the mechanism when the lower hood portion is pulled downward by a user. An upper hood portion of the body is configured so that when the lower hood portion is engaged with the clamp mechanism and pulled downward, the upper hood portion descends to cover the head portion of the tool including the slot. Outside light is then blocked from entering the slot and reaching the photo detectors whenever a fiber is tested by the tool, thus preventing false indications. | 10-16-2014 |
20140299059 | VAPOR DELIVERY SYSTEM - Vapor delivery systems for chemical depositions are shown in which the vapor delivery systems are capable of simultaneous buffering and fast response. The vapor delivery systems achieved the functionality using a two-volume system. The first volume mainly functions as a buffer to stabilize perturbations in vapor flow upstream. The second volume is smaller than the first volume so that the second volume responds to a change in vapor flow quickly. Optionally, a fixed flow restrictor is connected to the second volume and the fixed flow restrictor buffers downstream fluctuations. | 10-09-2014 |
20140294350 | Apparatus For Alignment of A Multicore Fiber in A Multifiber Connector And Method of Using Same - A multicore fiber alignment apparatus is described, having a chassis into which is mounted ferrule-holding means for holding a multicore fiber ferrule having one or more capillaries extending therethrough. Fiber-holding means for holding one or more multicore fibers in position to be mounted into the ferrule, such that each multicore fiber extends through a respective ferrule capillary. Means are provided for monitoring the rotation angle of each multicore fiber within its respective capillary, relative to a reference rotational orientation. Means are further provided for rotating each of the multicore fibers within its respective capillary. The rotational orientation of each multicore fiber is fixed when its rotation angle is equal to zero. | 10-02-2014 |
20140270668 | REMOVING UNWANTED LIGHT FROM HIGH-POWER OPTICAL SYSTEMS - The present disclosure is directed to removing unabsorbed cladding light in high-power optical systems. Some embodiments comprise a glass block with a refractive index that is greater than a refractive index of a fiber cladding, and a metal housing that is located external to the glass block. The glass block and the metal housing, in combination, removes excess light. | 09-18-2014 |
20140270667 | Glass Buffers - The present disclosure is directed to optical fibers having glass buffers. As such, some embodiments comprise an optical fiber having a core, a cladding, and a glass buffer. For some embodiments, the glass buffer has an index of refraction that is greater than the index of refraction of the cladding. | 09-18-2014 |
20140270665 | LARGE CORE MULTIMODE OPTICAL FIBERS - The specification describes multimode optical fibers produced by improved methods that reduce the manufacturing cost. These methods may also be more efficient in terms of power loss. In one of the embodiments, the improved design has a large core of pure silica derived from a rod-in-tube method. In the embodiment, a down-doped cladding is produced by depositing fluorine-doped silica on the inside of a silica starting tube using isothermal radio frequency plasma deposition. The silica core is inserted and the starting tube collapsed. The silica starting tube is removed and optical fiber is drawn from the fluorine-doped glass coated silica rod. | 09-18-2014 |
20140270644 | RING COMBINER - A waveguide comprises an annular cross-section and a first numerical aperture (NA) at one end. The waveguide further comprises either an annular or circular cross-section at the other end, which has a second NA. The waveguide has a progressively-varying NA, which varies from the first NA (at one end) to the second NA (at the other end). | 09-18-2014 |
20140270643 | METHOD OF AND APPARARTUS FOR INSCRIPTION OF FIBER GRATINGS FROM MULTIPLE AZIMUTHAL ANGLES AND FIBER SO INSCRIBED - A method of, and apparatus for, inscribing a grating in an optical waveguide so as to reduce transverse inscription variations, are provided. The waveguide is exposed to multiple beams or interference patterns of actinic radiation from multiple azimuthal directions. The beams of actinic radiation are preferably split into a plurality of beams that have wave vectors with different longitudinal components, e.g., via gratings such as phase masks. The periods and phases of the interference patterns of the beams of actinic radiation are preferably matched. A control beam may be provided that does not hit the waveguide. A control loop optionally controls at least one of the position or orientation of at least one of the beams of actinic radiation. The gratings are, for example, Bragg gratings. | 09-18-2014 |
20140268311 | HIGH-POWER DOUBLE-CLADDING-PUMPED (DC) ERBIUM-DOPED FIBER AMPLIFIER (EDFA) - 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. | 09-18-2014 |
20140268278 | Optical Polarimeter - A polarimeter is proposed that utilizes additional Stokes parameter measurements to determine both an average Stokes vector, as well as any rotation of the state of polarization around the Stokes vector. The optical polarimeter is configured to measure the state of polarization (SOP) under multiple, different conditions that yield both averaged Stokes vector and at least one other secondary (filtered) Stokes vector, the latter thus being determined from a subset of the conditions used to create the average Stokes vector. The secondary Stokes vector created from a filtered input will necessarily exhibit changes over time as a function of polarization transformations (based on filter-dependent changes), while the average Stokes vector will retain a constant value. Thus, a comparison of the average Stokes vector to the changing secondary Stokes vector allows for these polarization-dependent transformations to be recognized. | 09-18-2014 |
20140263985 | OPTICAL SENSOR HAVING FIDUCIARY MARKS DETECTED BY RAYLEIGH SCATTERED LIGHT - An optical fiber having at least one fiduciary mark is provided. The at least one fiduciary mark is located at one or more axial positions along the optical fiber. The at least one fiduciary mark is configured to produce at least one change in a Rayleigh backscattering signal in the optical fiber. The at least one change in a Rayleigh backscattering signal may be an abrupt change in the Rayleigh backscattering signal. The abrupt change in the Rayleigh backscattering signal occurs over a length of the optical fiber that is of the order of or less than a spatial resolution of an interrogation system employed to detect the Rayleigh backscattering signal. | 09-18-2014 |
20140247453 | BROADBAND FIBER SENSOR ARRAY - A broadband fiber optic sensor array is formed along a length of single mode optical fiber, with the individual sensing elements formed by introducing local perturbations (e.g., changes in diameter) along the length of the optical fiber. The sensor array requires only a single light source input and a single (conventional) optical spectrum analyzer output and is capable of providing individual measurements (such as local temperature or pressure) for each sensing element disposed along the length of fiber. The individual transmission spectra of the sensing elements forming the array are smooth and strongly overlap, and a method has been developed for determining the characteristics of the individual elements from the variations in the total (combined) transmission spectrum. | 09-04-2014 |
20140233890 | INDEX MATCHED GRATING INSCRIPTION - The disclosed embodiments provide systems and methods for mitigating lensing and scattering as an optical fiber is being inscribed with a grating. The disclosed systems and methods mitigate the lensing phenomenon by surrounding an optical fiber with an index-matching material that is held in a vessel with an integrated interferometer (e.g., phase mask, etc.). The index-matching material has a refractive index that is sufficient to reduce intensity variations of the actinic radiation within the optical fiber. Some embodiments of the system include different vessels for holding the index-matching material, with the vessel having an interferometer integrated into the vessel. These vessels permit the optical fiber to be surrounded by the index-matching material while the gratings are written to the optical fiber. | 08-21-2014 |
20140233889 | INDEX MATCHED GRATING INSCRIPTION - The disclosed embodiments provide systems and methods for mitigating lensing and scattering as an optical fiber is being inscribed with a grating. The disclosed systems and methods mitigate the lensing phenomenon by surrounding an optical fiber with a liquid index-matching material that is held in a vessel. The disclosed systems also include a replenishment mechanism that replenishes the liquid index-matching material as the optical fiber is pulled through the vessel. | 08-21-2014 |
20140233888 | INDEX MATCHED GRATING INSCRIPTION - The disclosed embodiments provide systems and methods for mitigating lensing and scattering as an optical fiber is being inscribed with a grating. The disclosed systems and methods mitigate the lensing phenomenon by surrounding an optical fiber with an index-matching material that is held in a vessel with an integrated interferometer (e.g., phase mask, etc.). The index-matching material has a refractive index that is sufficient to reduce intensity variations of the actinic radiation within the optical fiber. Some embodiments of the system include different vessels for holding the index-matching material, with the vessel having an interferometer integrated into the vessel. These vessels permit the optical fiber to be surrounded by the index-matching material while the gratings are written to the optical fiber. | 08-21-2014 |
20140232997 | INDEX MATCHED GRATING INSCRIPTION - The disclosed embodiments provide systems and methods for mitigating lensing and scattering as an optical fiber is being inscribed with a grating. The disclosed systems and methods mitigate the lensing phenomenon by surrounding an optical fiber with an index-matching material that is held in a vessel with a sealed phase mask. The sealed phase mask allows it to be in contact with a liquid index-matching material without having the liquid index-matching material seep into the grooves of the sealed phase mask. Thus, for some embodiments, the sealed phase mask may be immersed in a liquid index-matching material without adversely affecting the function of the phase mask. | 08-21-2014 |
20140219660 | ARRANGEMENT FOR DEPLOYING CO-EXISTING GPON AND XGPON OPTICAL COMMUNICATION SYSTEMS - A passive, coexisting 10 Gb/s passive optical network (XGPON) and Gb/s passive optical network (GPON) is created by using a pair of counter-propagating laser pump sources at a network-based optical line terminal, in combination with a feeder fiber, to create distributed Raman amplification for the upstream signals associated with both GPON and XGPON systems. A passive remote node is located at the opposite end of the feeder fiber, in the vicinity of a group of end-user locations, and includes a cyclic WDM and a pair of power splitters for the GPON and XGPON signals such that the GPON signals are thereafter directed through a first power splitter into optical network units (ONUs) specifically configured for GPON wavelengths and XGPON signals are directed through a second power splitter into ONUs configured for the XGPON wavelengths. The arrangement of the remote node allows for the reach and split ratios of the GPON and XGPON systems to be individually designed for optimum performance. | 08-07-2014 |
20140218733 | IN-LINE ARRANGEMENT FOR MEASURING POLARIZATION EXTINCTION RATIO - An in-line polarization extinction ratio (PER) monitor that generates a value of an optical signal's PER from a single measurement, without requiring the optical transmission signal path of the system to be directly coupled into a separate measurement device. The polarization extinction ratio may be defined as: 10 log(P | 08-07-2014 |
20140211198 | METHOD OF FABRICATING SURFACE NANOSCALE AXIAL PHOTONIC DEVICES - A method of characterizing and correcting effective radius variations in a surface nanoscale axial photonic (SNAP) device that comprises a plurality of separate optical microdevices includes the steps of characterizing an as-fabricated SNAP device to determine local effective radius values of the plurality of separate optical microdevices, calibrating the as-fabricated SNAP device to determine a correction factor defined as a change in effective radius associated with a predetermined corrective treatment and then correcting individual microdevices by the application of a number of refractive index-changing treatments, the number of treatments applied to individual microdevices determined by the amount of correction required and the correction factor determined in the calibrating step. A number of iterations of the characterizing and correcting operations can be performed, achieving less than an Angstrom variation in effective radius variation. An apparatus for performing the method is also disclosed. | 07-31-2014 |
20140205251 | COLOR CODED OPTICAL FIBERS - The specification describes an optical fiber color coding scheme that uses two colors, where each of the two colors constitutes one half of the surface of the optical fiber coating. If a longitudinal portion of the coating is considered a hollow cylinder, then each of the two colors is a hollow hemi-cylinder. To ensure that each of the two colors is always plainly visible to an installer, the two colors are formed with a twist. Using two colors for coding substantially increases the number of available unique color codes. Coloring the entire coating reduces the chances of error in identifying the optical fibers. | 07-24-2014 |
20140186645 | MANUFACTURE OF BEND INSENSITIVE MULTIMODE OPTICAL FIBER - A method of assembling a preform for a bend-insensitive multimode optical fiber (BIMMF), includes providing a multimode core rod, a glass overclad tube, and a trench tube of down-doped quartz glass with a depressed refractive index sufficient to obtain a desired trench depth in a refractive index (RI) profile of a drawn fiber. The core rod is placed inside the trench tube, and the trench tube and the core rod are placed inside the overclad tube to define the preform. A top end of the trench tube is formed to contact an adjacent part of either the core rod or the overclad tube so that the trench tube is suspended to hang from the adjacent part when the preform is vertically oriented, and a bottom end of the trench tube is restrained from sinking into a lower portion of the preform when the preform is heated to collapse. | 07-03-2014 |
20140169747 | SPLICING TWISTED MULTIPLE CORE OPTICAL FIBERS - A method of coupling optical fibers containing cores or other structures that twist about the axis of one or both fibers. The fiber end faces are aligned axially to confront one another, and side view images of end regions of the fibers including the contained cores or structures are produced. For each fiber, a brightness profile of a side view image is obtained at an axially offset position from the fiber end face. One or both fibers are rotated about their axes until the brightness profiles for each fiber indicate certain cores or structures in the fibers are aligned. For each fiber, an additional amount of twist from the offset position to the fiber end face is determined. One or both fibers are rotated again to compensate for the additional twist in each fiber, so that the fibers are aligned optimally when coupled. | 06-19-2014 |
20140161404 | Multicore Fiber Designs for Spatial Multiplexing - In an optical fiber, a plurality of individual cores extend through a common cladding. Each individual core supports at least one local transverse spatial mode. The individual cores and surrounding cladding are structured to support propagation of plurality of desired signal-carrying modes, while suppressing undesired modes, thereby supporting the propagation of one or more spatially multiplexed signals. The core-to-core spacing of the fiber is configured to maintain an acceptably low level of mode-coupling between cores. | 06-12-2014 |
20140140693 | METHODS AND SYSTEMS FOR BULK DISPERSION MONITORING - A method and system for measuring chromatic dispersion, experienced by ASK/PSK modulated optical signals, are provided. Dispersion measurement is enabled either by encoding an additional overhead at lower baud rate or by monitoring signal SOP or RF spectrum of signal SOP. The bulk chromatic dispersion of the link is measured by analyzing the dispersion broadening of the overhead constellation or signal temporal diagram, or time-overlapped signal diagram, or overhead spectrum. This information is used to reduce the computation time required for electronic recovery of a highly dispersed signal. | 05-22-2014 |
20140139907 | FIBER STRETCHER MODULE FOR USE IN THE 1550 NM WAVELENGTH RANGE - Embodiments of the present invention are generally related to embodiments of the present invention relate to a fiber stretchers module for use in the 1550 nm wavelength range. In one embodiment of the present invention, a fiber stretcher module for use in the 1550 nm wavelength range comprises a first fiber comprising a relative dispersion curve value of greater than about 0.0002 nm | 05-22-2014 |
20140125971 | DEVICE AND METHOD TO MEASURE THE DMD AND OTHER PARAMETERS OF A MULTICORE OPTICAL FIBER - Apparatus and method of simultaneously measuring a parameter of a plurality of cores in at least one optical fiber. An input tester at a first end of the test fiber has a plurality of tester signal inputs with a geometry substantially matching at least a portion of the core geometry of the fiber. At least one test input signal source coupled to the plurality of tester signal inputs. A signal measuring device is alignable at a second end of the fiber to measure the output of the test input signal. The input tester may include a tapered multicore coupler or a laser having a shield with apertures disposable between the laser and the fiber. In the latter case, a lens may be disposed between the shield and the fiber to project light from the laser that passes through the apertures onto the end of the fiber. | 05-08-2014 |
20140119700 | NON-LINEAR FIBER RESISTANT TO PERTURBATIONS - Embodiments of the present invention relate to a fiber design that achieves high nonlinearity, an effective index providing phase matching for an illustrative wavelength conversion process, and a low sensitivity to perturbations in fiber scaling. In one embodiment, a fiber comprises an inner core having an inner core radius and an inner core index, an outer core having an outer core radius and an outer core index, the outer core index being lower than the inner core index, an inner cladding, having an inner cladding radius and an inner cladding index, the inner cladding index being less than the outer core index, and an effective index of the fiber, the effective index being greater than the inner cladding index and less than the outer core index, wherein the fiber has a low perturbation sensitivity factor of dispersion to scaling less than about 20 ps/nm/km along the length of the fiber. | 05-01-2014 |
20140119694 | Techniques and Devices for Low-Loss Coupling to a Multicore Fiber - An optical pedestal fiber is configured to be taperable to form a tapered fiber having a mode field diameter at the tapered end that differs from the mode field diameter at the untapered end in correspondence with the difference between the cladding diameter at the tapered end and the cladding diameter at the untapered end. A plurality of such pedestal fibers can be used to construct a tapered fiber bundle coupler that provides matching of both core pitch and mode field diameter between a plurality of input fibers and individual cores of a multicore fiber. Further, the tapered fiber bundle coupler can be constructed using a plurality of fibers, in which individual fibers are configured to have different effective refractive indices, thereby suppressing crosstalk therebetween. | 05-01-2014 |
20140093205 | Step-Index Few-Mode Fiber Designs For Spatial Multiplexing - A few-mode optical fiber comprises a core surrounded by a cladding, having a step index profile that is structured to support propagation of a plurality of desired signal-carrying modes, while suppressing undesired modes. The core and cladding are configured such that the undesired modes have respective effective indices that are close to, or less than, the cladding index such that the undesired modes are leaky modes. The index spacing between the desired mode having the lowest effective index and the leaky mode with the highest effective index is sufficiently large so as to substantially prevent coupling therebetween. | 04-03-2014 |
20140064686 | MULTIPLE LP MODE FIBER DESIGNS FOR MODE DIVISION MULTIPLEXING - The specification describes modified step index and GRaded INdex (GRIN) fibers with low core relative delta (near 0.8%) which have desirable properties for transmission. These lower delta fibers have lower attenuation losses due to reduced Rayleigh scattering, which is desirable to improve performance in multiple mode multiplexing. The fiber designs include optimized raised triangle profiles, and depressed cladding profiles, to support two and four LP modes. | 03-06-2014 |
20140064682 | Liquid and Gaseous Resistance Compact Fiber Unit and Method of Making the Same - The embodiments disclosed herein seek to eliminate substantially all of the voids or air gaps among neighboring fibers within a CFU by wetting a plurality of optical fibers that comprises the CFU with an acrylate prepolymer resin before the plurality of the optical fibers are grouped together tightly. In one embodiment, instead of extruding a first acrylate prepolymer resin to the optical fibers immediately after a first die, the disclosed process wets the optical fibers with a first acrylate prepolymer resin prior to the first die. | 03-06-2014 |
20140054451 | DBF FIBER LASER BEND SENSOR AND OPTICAL HETERODYNE MICROPHONE - Methods and systems using one or more distributed feedback (DFB) lasers for capturing changes in the lasing environment are disclosed. Specifically, a sensor for measuring a measurand, such as pressure or temperature, or changes in a measurand, includes a fiber with at least one core, at least one fiber laser cavity formed by a single fiber grating in the core, wherein the laser operates on at least two modes along at least part of its length. The DFB laser includes a section that is bent into a non-linear shape and at least one pump laser connected to the fiber laser cavity. When the DFB laser experiences a perturbation or measurand change that changes the spacing of the modes, a change in an RF beat note is generated. This beat note can then be measured and related to the measurand change. | 02-27-2014 |
20140020815 | Preparing And Attaching A Communication Line To A Supporting Surface On Or Inside Of A Building - A communication line such as an optical fiber or cable is attached along a wall, ceiling, trim piece, or other selected surface on or inside of a building, by paying out the fiber from an applicator tool while the tool guides the fiber along the selected surface. The outer surface of the fiber is prepared so that the fiber will be in a temporarily tacky condition when the fiber is pressed onto the selected surface by the applicator tool. The fiber is pre-coated with an adhesive that is activated by a fluid supplied by the applicator tool. As the applicator tool presses the fiber onto the selected surface, the activated adhesive coating on the fiber quickly becomes non-tacky to attach the fiber firmly to the surface. | 01-23-2014 |
20130333822 | Methods For Routing An Optical Fiber Or Cable Inside A Building Or Living Unit of Customer Premises - Methods for routing an optical fiber over a desired span on a structural surface at a given premises are provided. When the optical fiber is unwound from a container, the optical fiber attaches to the structural surface by an adhesive material. The adhesive material can be applied along the desired span before, during, or after the optical fiber is routed over the desired span. | 12-19-2013 |
20130323414 | ACCELERATED AGING OF PHOSPHORUS-DOPED OPTICAL FIBERS - Adverse hydrogen aging limitations in multiply-doped optical fibers are overcome by passivating these optical fibers using a deuterium passivation process. This treatment essentially pre-reacts the glass with deuterium so that the most active glass sites are no longer available to react with hydrogen in service. Optical fibers of main interest are doped with mixtures of germanium and phosphorus. Optimum passivating process conditions are described. | 12-05-2013 |
20130322819 | NA Reduction In Fiber Optical Couplers - A fiber optical coupler comprises a bundle of optical fibers configured to couple light from a multiplicity of input light sources to an output port, each of the fibers comprising a multimode fiber having a core region and a cladding region surrounding the core region. The bundle has first and second axial sections arranged in tandem and adiabatically coupled to one another via a transition zone that includes an optical interface. Within the first section, the ratio of the cross-sectional core area of each of at least some of the fibers to the total cross-sectional area of each of those fibers is given by R | 12-05-2013 |
20130315540 | OPTICAL CONNECTOR FOR CABLES HAVING A BEND INSENSITIVE FIBER - An optical connector has a housing, and a retention member for retaining a cable with a fiber that has a specified minimum bend radius. A rear portion of a connector ferrule and spring are seated in the retention member, a front end of the member engages the connector housing, and the spring urges the ferrule toward the front of the connector housing. An elongated cable support has an axial passage that opens at a front end and at a back end of the support for receiving the cable, and the front end of the support is joined at the rear of the retention member. The passage in the support has a radially outward flare at the back end which acts to limit the cable from bending in the vicinity of the connector, so that the cable fiber is not strained below the specified minimum bend radius. | 11-28-2013 |
20130259429 | MULTI-FERRULE CONNECTOR FOR MULTICORE FIBER TERMINATIONS - A ganged connector housing Is configured to receive a plurality of single-fiber connectors. Each connector is removably retainable at a respective location in the connector housing. Each single-fiber connector comprises a ferrule configured to receive and retain a single multicore fiber. The single-fiber connectors have a high-density packing footprint within the connector housing. Each single-fiber connector and its respective ferrule is configured to enable individual repositioning, tuning, alignment, repair or replacement of a respective multicore fiber terminated therein, independent of other optical fibers within the plurality of single fiber ferrules, and without requiring replacement of the entire set of multicore fibers. | 10-03-2013 |
20130251324 | Large Mode Area Optical Fibers With Bend Compensation - 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 γn | 09-26-2013 |
20130251321 | Optical Fiber Cables - Described are new cable designs for indoor installations wherein the cable comprises a dual-layer optical fiber buffer encasement of acrylate resin. The buffer encasement has an acrylate compliant inner layer that protects the fiber and minimizes stress transfer to the fiber; and a hard, tough acrylate outer layer that provides crush resistance. The dual-layer optical fiber buffer encasement is wrapped with reinforcing yarn and encased in an outer protective jacket. A dual jacket embodiment adapted for indoor/outdoor installations is also described. | 09-26-2013 |
20130243949 | Modular Method of Making Single Mode Optical Fibers - Described is a modular method of making an optical fiber comprising a core and a cladding configured to support and guide a fundamental transverse mode, the cladding including (i) an outer cladding having an index n | 09-19-2013 |
20130231906 | Statistical Prediction Functions For Natural Chaotic Systems And Computer Models Thereof - Embodiments generally relate to methods of accurately predicting seasonal fluctuations in precipitation or other approximate functionals of a climate state space, such as the number of heating or cooling degree days in a season, maximum river flow rates, water table levels and the like. In one embodiment, a method for predicting climate comprises: deriving a climate attractor from a global climate model, wherein a tuning parameter for the climate attractor comprises a value of total energy for moving air and water on the earth's surface; estimating a predictive function for each of a plurality of computational cells within the global climate model; and predicting an approximate climate functional of interest for a given specific location utilizing a combination of the predictive functions from each of the plurality of computational cells geographically proximate the location, where at all stages, predictive functions are selected in part by comparison to historical data. | 09-05-2013 |
20130230061 | FIBER LASER CAVITY OPTICAL ENGINE PACKAGE AND METHOD OF MAKING THE SAME - Embodiments of the invention include a fiber laser cavity package having improved fiber management and thermal management capability and methods of making such fiber laser cavity package. Each element of the fiber laser cavity is grouped into plurality of sections and each section is placed onto a heat conducting surface within the fiber laser cavity package to dissipate unwanted heat from the elements. When the fiber laser cavity is stored in the package, the fiber laser cavity is arranged such that fiber crossings are substantially reduced or eliminated within the package. | 09-05-2013 |
20130223851 | Dispersion-Compensating System And Dispersion-Compensating Fiber with Improved Figure of Merit - A dispersion-compensating system and a dispersion-compensating fiber have an improved figure of merit and effective area. The dispersion-compensating system comprises a bulk dispersion-compensating module for providing optical-domain bulk dispersion compensation for an optical signal transmission. Additionally, the system may further comprise residual dispersion compensation, which can be performed in the electrical domain following coherent detection of both amplitude and phase of an optical signal. The dispersion-compensating fiber comprises an up-doped core region; a down-doped trench; an up-doped ring; and an outer cladding, and is configured to have a high figure of merit (FOM). | 08-29-2013 |
20130219970 | MICROBUBBLE OPTICAL RESONATOR - An optical microresonator is configured as an optical microbubble formed along a section of an optical microcapillary. The curvature of the outer surface of the microbubble creates an optical resonator with a geometry that encourages the circulating WGMs to remain confined in the central region of the bubble, creating a high Q optical resonator. The resonator may be tuned by modifying the physical properties of the microbubble, allowing the resonator to be used as an optical filter. The resonator may also be used as a sensor or laser by introducing the material to be sensed (or the active laser material) into the microcapillary along which the microbubble is formed. | 08-29-2013 |
20130216194 | Controlling Differential Group Delay In Mode Division Multiplexed Optical Fiber Systems - It has been discovered that within a group of optical fibers produced by methods designed to produce low Differential Group Delay (DGD), some optical fibers will show a positive DGD while others will show a negative DGD. That recognition allows optical fibers with excessive DGD to be combined in pairs, or other configurations, to produce transmission spans in which a positive (or negative) DGD partial span is compensated by a partial span of fiber with a negative (or positive) DGD. | 08-22-2013 |
20130188949 | Techniques For Reducing Crosstalk In Multicore Fibers - An optical fiber has two or more core regions disposed within a common cladding region. Each of the core regions is configured to guide a respective light transmission comprising at least one optical mode along the length of the fiber. The cores are arranged within the common cladding region according to a core configuration that substantially prevents crosstalk between modes of neighboring cores in the fiber, in a deployment of the fiber in which cross-coupling between neighboring cores is affected by perturbations arising in the deployed fiber. | 07-25-2013 |
20130176557 | High Q-Factor Conical Optical Microresonator And Utilization In The Location Characterization Of Optical Fibers - A conically tapered optical fiber with a small half-angle γ (e.g., less than 10 | 07-11-2013 |
20130161295 | Laser Cavity Exhibiting Low Noise - Inventive single cavities for use in a high power fiber laser systems are described that include a high reflective grating, a gain fiber, an output coupler having a bandwidth in the range of 1 nm to 2 nm; and an output fiber connected to the single cavity that supplies power from the single cavity. The single cavity can be used in a wide variety of applications, including welding, cutting, brazing or drilling a material, or to seed a downstream amplifier. | 06-27-2013 |
20130091899 | Method Of Making An Optical Fiber With Trench Region In Its Index Profile - An optical fiber that is relatively insensitive to bend loss and alleviates the problem of catastrophic bend loss configured to support and guide the propagation of light in a fundamental transverse mode. The cladding region includes an outer cladding region, a pedestal region, an inner trench region, and an outer trench region. The pedestal region and the outer cladding region each have a refractive index relatively close to that of the outer cladding region. To suppress HOMs the pedestal region is configured to resonantly couple at least one (unwanted) transverse mode of the core region (other than the fundamental mode) to at least one transverse mode of the pedestal region. Also described are multi-tube fabrication techniques for making such fibers as well as single-pass/double-pass fabrication techniques for making the trench regions of such fibers. | 04-18-2013 |
20130084042 | DAMAGE RESISTANT FIBER OPTIC CONNECTOR - A fiber optic connector has a connector body, an elongated ferrule supported in the connector body, and a sleeve fixed on the circumference of a distal tip of the ferrule. The ferrule has an axial passage that opens on a front surface of the tip so that an endface of a fiber retained in the passage is exposed at the front surface. Further, the sleeve has a leading edge that projects a determined distance axially beyond the front surface of the tip to form a recessed region in which the exposed endface of the fiber is set back from the leading edge of the sleeve. A barrier is contained in the recessed region for protecting the fiber endface from damage by surrounding objects. The barrier may include a cured epoxy layer, a lens, or a refractive index matching material optically aligned with the fiber endface. | 04-04-2013 |
20130071081 | Optimized Ultra Large Area Optical Fibers - Certain embodiments of the invention may include optimized trench-assisted ultra large area (ULA) optical fibers. According to an example embodiment of the invention, a trench-assisted optical fiber, optimized for figure-of-merit (FOM) performance, is provided. The optical fiber includes a core region having a longitudinal axis, a shelf region surrounding said core region, a cladding region surrounding said shelf region, said core and shelf and cladding regions configured to support and guide the propagation of signal light in a fundamental transverse mode in said core and shelf regions in the direction of said axis.. The optical fiber further includes a core effective area (Aeff) of between 135 μm | 03-21-2013 |
20130071080 | Optimized Ultra Large Area Optical Fibers - Certain embodiments of the invention may include optimized trench-assisted ultra large area (ULA) optical fibers. According to an example embodiment of the invention, a trench-assisted optical fiber, optimized for figure-of-merit (FOM) performance is provided. The optical fiber includes a core region having a longitudinal axis, a shelf region surrounding said core region, a cladding region surrounding said shelf region, said core and shelf and cladding regions configured to support and guide the propagation of signal light in a fundamental transverse mode in said core and shelf regions in the direction of said axis. The optical fiber further includes a core effective area (Aeff) of between 135 μm | 03-21-2013 |
20130071079 | Optimized Ultra Large Area Optical Fibers - Certain embodiments of the invention may include optimized trench-assisted ultra large area (ULA) optical fibers. According to an example embodiment of the invention, a trench-assisted optical fiber, optimized for microbending and figure-of-merit (FOM) performance is provided. The optical fiber includes a core region having a longitudinal axis, a shelf region surrounding said core region, a cladding region surrounding said shelf region, said core and shelf and cladding regions configured to support and guide the propagation of signal light in a fundamental transverse mode in said core and shelf regions in the direction of said axis, the cladding region including an inner trench and an outer trench. The optical fiber further includes a core effective area (Aeff) of between 135 μm | 03-21-2013 |
20130038923 | FIBER ASSEMBLY FOR ALL-FIBER DELIVERY OF HIGH ENERGY FEMTOSECOND PULSES - Embodiments of the present invention are generally related to a fiber assembly, for example, in a chirped pulse amplification system, for all-fiber delivery of high energy femtosecond pulses. More specifically, embodiments of the present invention relate to a system and method for improving dispersion management when using hollow core photonic bandgap fibers for pulse compression. In one embodiment of the present invention, a fiber assembly comprises: an optical laser oscillator; a first fiber section for stretching the pulses from the laser oscillator, the first fiber section comprising a high order mode fiber; and a second fiber section for compressing the stretched pulses, connected to the first fiber section via a splice, the second fiber section comprising a hollow core photonic bandgap fiber; wherein the fiber assembly outputs a pulse compression at less than 200 fs. | 02-14-2013 |
20130020015 | Apparatus and Methods for Routing an Optical Fiber or Cable Inside a Building or Living Unit - Apparatus and methods for routing an optical fiber over a desired span on a structural surface at a given premises are provided. When the optical fiber is unwound from a spool, the optical fiber attaches to the structural surface by an adhesive material. The adhesive material can be applied along the desired span, or portion thereof, before, during, or after the optical fiber is routed over the desired span. | 01-24-2013 |
20130016950 | Optical Fiber Modules Encapsulated by Flame Retardant Silicone - Certain embodiments of the invention may include an optical fiber modules encapsulated by flame retardant encapsulant. According to an example embodiment of the invention, an optical fiber module is provided. The optical fiber module comprises an optical fiber shaped to form one or more loops within the module, and a flame retardant encapsulant covering any exposed portion of the optical fiber. The flame retardant encapsulant is rated UL94 V-1 or better. The loop portion of the optical fiber may be affixed permanently within the module and any exposed surface of the fiber is coated with the encapsulant. | 01-17-2013 |
20130011108 | UV Curable Acrylate Buffer Coating for Optical Fiber - Certain embodiments of the invention may include a UV curable acrylate buffer coating for optical fiber. According to an example embodiment of the invention, a buffered optical fiber is provided. The buffered optical fiber includes a core, a cladding surrounding the core, a primary layer surrounding the cladding, a secondary layer surrounding the primary layer. A clear or translucent buffer surrounds the optical fiber, wherein the buffer includes polyester/polyether polyol aliphatic urethane acrylate, and the buffer has an elastic modulus greater than 40,000 psi. | 01-10-2013 |
20120301077 | Adiabatic Coupler For Coiled Optical Fiber Devices - An optical fiber coupler is formed of a section of optical fiber that is positioned between a conventional input fiber (for example, a single mode fiber) or waveguide and a coiled optical fiber device. The adiabatic coupler is coiled (or, at least, curved) to assist in transforming a conventional fundamental mode optical signal propagating along the longitudinal axis of the input fiber to an optical signal that is shifted into a peripheral region of the coiled optical fiber. Moreover, the pitch of an inventive coiled optical fiber coupler can be controlled to assist in the adiabatic transformation process. | 11-29-2012 |
20120237164 | Spatial Filtering of Higher Order Modes in Multimode Fibers - A mode filter for eliminating the propagation of higher-order modes along a section of optical multimode fiber comprises a graded index (GRIN) lens, preferably of a quarter-pitch length, and a pinhole element in the form of a small core fiber. This configuration creates a Fourier spatial filter assembly that removes higher order modes propagating along an optical fiber while capturing the fundamental mode of the optical signal. A section of GRIN fiber is preferably used as the lens, with the small core fiber disposed at the output of the GRIN fiber lens to collect substantially only the on-axis fundamental mode of the optical signal. Since the higher order modes are shifted away from the origin by the GRIN fiber lens, only the fundamental mode signal is captured by the small core fiber. | 09-20-2012 |
20120224597 | METHOD AND SYSTEM FOR ULTRASHORT PULSE FIBER DELIVERY USING HIGHER ORDER MODE FIBER - Embodiments of the present invention describe systems and methods for delivering ultrashort laser pulses through an optical fiber system with higher order mode fiber output and without pre-chirping. In one embodiment of the present invention, an all-fiber delivery system comprises a mode-locked solid-state or fiber laser for generating laser pulses in the 0.2 μm to 1.3 μm wavelength range, a single mode fiber with normal dispersion, and a long-period-grating mode converter, and a higher order mode fiber with anomalous dispersion, wherein the all-fiber delivery system is free of bulk optics, and propagates laser pulses without pulse pre-chirping, and wherein higher order mode output beam from the all-fiber delivery system comprises pulses at less than about 200 femtoseconds. | 09-06-2012 |
20120219255 | CONNECTORS FOR USE WITH POLARIZATION-MAINTAINING AND MULTICORE OPTICAL FIBER CABLES - An optical fiber ferrule has a plurality of guide holes therein for guiding a respective plurality of flat-sided fibers at an end of a multifiber optical fiber cable. The fibers' flat sides identify a particular rotational orientation of the fiber. Rotational alignment is achieved by urging the fibers' flat sides against a corresponding reference surface within the ferrule or within an alignment fixture. Also described is a fiber array block having a plurality of V-shaped grooves extending across an outer surface and terminating at an endface. The V-shaped grooves are shaped to guide a respective plurality of flat-sided fibers. A lid is installable across the plurality of V-shaped grooves, over fibers that have been loaded therein. | 08-30-2012 |
20120219254 | SINGLE-FIBER CONNECTORS FOR OPTICAL FIBER CABLES - An optical fiber cable connector includes a ferrule with a guide hole that is shaped to closely receive a multicore fiber having a flat side indicative of the rotational orientation of the cores of the multicore fiber. The ferrule includes a flat surface at one side of the guide hole, corresponding in position to the flat side of the multicore fiber. Installing the multicore fiber into the guide hole with its flat side abutting the flat surface along the side of the guide hole provides alignment of the cores with respect to an optical component to which the multicore fiber endface is to be connected. | 08-30-2012 |
20120213474 | Coupled Photonic Microdevices With Sub-Wavelength Feature Size - Complex, coupled photonic microdevices are formed to include sub-wavelength-sized radial perturbations sufficient to create resonant cavities, where these devices may be formed along the length of a single optical fiber and coupled together to form relatively complex photonic devices. By carefully selecting the placement and separation of these local radius variations, and using microfibers (or other suitable arrangements) to couple optical signals into and out of the device fiber, resonances in the form of whispering gallery modes (WGMs) are created in the device fiber such that a number of coupled microstructures (such as ring resonators) may be formed. | 08-23-2012 |
20120160167 | External Heating of Substrate Tubes in Plasma Chemical Vapor Deposition Processes - A PCVD apparatus including an insulative covering disposed to surround at least a portion of the substrate tube and provide external heating of the substrate tube during the deposition process. The insulative covering functions to capture and retain the external thermal energy created by the plasma process. As a result, the areas of the substrate tube that are removed from the current location of the plasma absorb this captured thermal energy and remain at an essentially constant temperature until the next pass of the work coil. | 06-28-2012 |
20120105831 | MEASURING MODAL CONTENT OF MULTI-MODED FIBERS - The output modal content of optical fibers that contain more than one spatial mode may be analyzed and quantified by measuring interference between co-propagating modes in the optical fiber. By spatially resolving the interference, an image of the spatial beat pattern between two modes may be constructed, thereby providing information about the modes supported by the optical fiber. Measurements of the phase front exiting the optical fiber under test are advantageously performed in the far field. | 05-03-2012 |
20120093461 | Production of Optical Pulses At A Desired Wavelength Utilizing Higher-Order-Mode (HOM) Fiber - An apparatus and method for producing optical pulses of a desired wavelength utilizes a section of higher-order-mode (HOM) fiber to receive input optical pulses at a first wavelength, and thereafter produce output optical pulses at the desired wavelength through soliton self-frequency shifting (SSFS) or Cherenkov radiation. The HOM fiber is configured to exhibit a large positive dispersion and effective area at wavelengths less than 1300 nm. | 04-19-2012 |
20120067997 | Optical Fiber Spool Inspection System - Methods and systems for inspecting a bare optical fiber spool are disclosed. The system inspects the bare optical fiber spool prior to optical fiber winding and determines whether the bare optical fiber spool is acceptable for the winding. | 03-22-2012 |
20120020635 | TOOL FOR ROUTING AN OPTICAL FIBER OR CABLE AT A LIVING UNIT OF CUSTOMER PREMISES - A tool for routing an optical fiber or a cable over a desired span on a visible supporting surface at a given premises. The tool includes a rod with a handle, and a reel or spool is mounted on the rod for storing a length of an optical fiber or a cable to be routed. An adhesive coating assembly is fixed on the rod for providing an adhesive on the fiber when the fiber is unwound from the spool during use of the tool. A fiber routing applicator is disposed at the distal end of the rod. The routing applicator is dimensioned and arranged to travel over the supporting surface at the premises to route the fiber with the adhesive thereon over the desired span, while urging the fiber against the surface so that the fiber adheres to the surface. | 01-26-2012 |
20120010842 | Self-Calibration Procedure For Optical Polarimeters - A procedure for self-calibration of an optical polarimeter has been developed that eliminates the need for “known” input signals to be used. The self-calibration data is then taken by moving a polarization controller between several random and unknown states of polarization (SOPs) and recording the detector output values (D | 01-12-2012 |
20110280517 | TECHNIQUES AND DEVICES FOR LOW-LOSS, MODEFIELD MATCHED COUPLING TO A MULTICORE FIBER - Devices and techniques are described for connecting each of plurality of terminals to respective individual cores of a multicore fiber. Each of the plurality of terminals is provided with a respective length of a single-core fiber. The single-core fibers are configured to maintain modal properties that arc substantially the same, within a tolerance range, at the front and rear ends, as the single-core fiber is tapered. The single-core fibers are assembled together. The front end of the assembly is tapered to form a front cross-section in which the single-core fiber cores are arranged in a configuration matching that of the cores of the multicore fiber. | 11-17-2011 |
20110279888 | MULTICORE TRANSMISSION AND AMPLIFIER FIBERS AND SCHEMES FOR LAUNCHING PUMP LIGHT TO AMPLIFIER CORES - An optical transmission and amplification system includes a multichannel transmission span with a length of a multicore transmission fiber having a plurality of individual transmission cores. A first tapered multicore coupler provides connectivity between the plurality of transmission cores of the multicore fiber and a respective plurality of individual transmission leads. A fiber amplifier is provided having a plurality of individual cores including at least one pump core and a plurality of amplifier core. A second tapered multicore coupler provides connectivity between the amplifier cores of the fiber amplifier and a respective plurality of amplifier leads, and between the at least one pump core and a respective pump lead. | 11-17-2011 |
20110274435 | MULTICORE FIBER TRANSMISSION SYSTEMS AND METHODS - An optical data link includes first and second pluralities of transmission devices, at least one of which is configured as an array. A multichannel transmission link has a first end connected to the first plurality of transmission devices and a second end connected to the second plurality of transmission devices so as to form a plurality of parallel transmission channels therebetween. The multichannel transmission link includes a multicore fiber with a plurality of individual cores having a configuration matching the array configuration of the at least one plurality of transmission devices. The multicore fiber has an endface connected directly to the at least one plurality of transmission devices, with the individual cores of the multicore fiber aligned with respective devices in the at least one plurality of transmission devices. Further described are access networks and core networks incorporating a transmission link comprising at least one span of a multicore fiber. | 11-10-2011 |
20110274398 | MULTICORE FIBERS AND ASSOCIATED STRUCTURES AND TECHNIQUES - A multicore fiber comprises a plurality of cores extending along the length of a fiber body. Each of the cores is surrounded by a cladding. The plurality of cores and surrounding cladding provide respective index variations, so as to form a respective plurality of waveguides for conducting parallel data transmissions from a first end of the fiber to a second end. The plurality of cores has a cross-sectional geometry in which the plurality of cores is configured in a polygonal array, in which at least some of the cores are positioned at the vertices of the array. The polygonal array is configured such that neighboring cores in the array are separated from each other by a distance that is sufficient to prevent crosstalk therebetween. | 11-10-2011 |
20110274397 | TIGHT-BUFFERED OPTICAL FIBER HAVING IMPROVED FIBER ACCESS - Certain embodiments of the invention may include systems and methods for providing tight-buffered optical fiber having improved fiber access. According to an example embodiment of the invention, a method for making a tight buffer upcoated optical fiber having a predetermined buffer stripping force is provided. The method includes controlling residual acrylate unsaturation (RAU) and oxygen in at least an outer surface of un-buffered optical fiber to achieve a predetermined buffer stripping characteristic, applying a tight buffer composition comprising acrylate to the un-buffered optical fiber, and curing the tight buffer composition. | 11-10-2011 |
20110262148 | COMPACT PLENUM-RATED RIBBON CABLES - Embodiments of the present invention include an optical fiber cable for use in a plenum. The cable comprises a tube, at least one optical fiber ribbon positioned within the tube, the optical fiber ribbon having a width (W), a jacket around the tube, the jacket having an outer diameter (D) and a limited oxygen index (LOI) of approximately at least 65%, at least two longitudinal strength members positioned between the tube and an outer surface of the jacket; and a yarn positioned between the tube and the jacket, wherein the ratio of the width (W) of the optical fiber ribbon and the outer diameter (D) of the jacket is approximately at least 0.25. | 10-27-2011 |
20110229086 | MULTIFIBER CONNECTORS FOR MULTICORE OPTICAL FIBER CABLES - Structures and techniques are described relating to the alignment of multicore fibers within a multifiber connector. These structures and techniques include: multicore fibers having a number of different shapes, including, for example, circular, elliptical, D-shaped, double D-shaped, and polygonal; multifiber ferrules, having a plurality of fiber guide holes therein of various shapes; alignment fixtures for aligning multicore fibers within multifiber ferrules; and various multicore fiber alignment techniques. | 09-22-2011 |
20110229085 | SIMPLEX CONNECTORS FOR MULTICORE OPTICAL FIBER CABLES - An optical fiber cable connector includes a ferrule subassembly, in which a ferrule is mounted into a receptacle including a barrel section having a flange at its base. The ferrule subassembly is loaded into an enclosure having a plug housing at its lead end. The plug housing is configured to provide a connection between an endface of a multicore fiber mounted into the ferrule and a corresponding surface in a mating socket. A collar is rotatably mounted onto the barrel section of the ferrule subassembly such that it butts up against the flange. The collar has an opening that fits around the barrel section, and an outer perimeter that fits into a receiving cavity with the plug housing. The ferrule, receptacle, receptacle barrel section, mounted multicore fiber, enclosure, and plug housing have a common longitudinal axis. As a result, the ferrule, receptacle, receptacle barrel section, and mounted multicore fiber are continuously rotatable with respect to the enclosure and plug housing, thereby enabling a precise rotational alignment of the multicore fiber within the enclosure. | 09-22-2011 |
20110210269 | Non-Linear Optical System and Techniques - Methods and systems are described using a non-linear optical system comprising a laser and a light delivery system comprising a single mode fiber, a mode converter, and a high order mode fiber, wherein the light delivery system that receives light from the source and provides a structured free-space beam having an embedded Gaussian beam. The light delivery system functions to illuminate a region of a sample and generate a non-linear response in a spatial region smaller than that associated with a Gaussian beam having a width comparable to the width of the embedded Gaussian beam. In another aspect, the light delivery system illuminates a region of a sample and generates a non-linear emission of radiation, is depicted. A further aspect of this embodiment includes an imaging assembly for detecting the non-linear emission and using a signal derived from the detected emission to generate a microscopic image of the sample. | 09-01-2011 |
20110194814 | BEND INSENSITIVITY IN SINGLE MODE OPTICAL FIBERS - An optical fiber that is relatively insensitive to bend loss comprises a core region and a cladding region configured to support and guide the propagation of light in a fundamental transverse mode, the cladding region including (i) an outer cladding region having a refractive index less than that of the core region, (ii) an annular cladding pedestal region having a refractive index higher than that of the outer cladding region and comparable to that of the core region, and (iii) an annular cladding inner trench region disposed between the core region and the pedestal region, the inner trench region having a refractive index less than that of the outer cladding region. In one embodiment, the fiber also includes a(iv) an annular cladding outer trench region disposed between the pedestal region and the outer cladding region, the outer trench region having a refractive index less than that of the outer cladding region. In addition, to suppress HOMs the pedestal region is configured to resonantly couple at least one other transverse mode of the core region to at least one transverse mode of the pedestal region. Such fiber is advantageously used as access fiber, but may have other applications, such as sensor fiber. | 08-11-2011 |
20110194813 | BEND INSENSITIVITY IN SINGLE MODE OPTICAL FIBERS - An optical fiber that is relatively insensitive to bend loss comprises a core region and a cladding region configured to support and guide the propagation of light in a fundamental transverse mode, the cladding region including (i) an outer cladding region having a refractive index less than that of the core region, (ii) an annular cladding pedestal region having a refractive index higher than that of the outer cladding region and comparable to that of the core region, and (iii) an annular cladding inner trench region disposed between the core region and the pedestal region, the inner trench region having a refractive index less than that of the outer cladding region. In one embodiment, the fiber also includes a (iv) an annular cladding outer trench region disposed between the pedestal region and the outer cladding region, the outer trench region having a refractive index less than that of the outer cladding region. In addition, to suppress HOMs the pedestal region is configured to resonantly couple at least one other transverse mode of the core region to at least one transverse mode of the pedestal region. Such fiber is advantageously used as access fiber, but may have other applications, such as sensor fiber. | 08-11-2011 |
20110188822 | OPTICAL FIBER COATINGS FOR REDUCING MICROBEND LOSSES - Certain embodiments of the invention may include systems and methods for providing optical fiber coatings to reduce microbend losses. According to an example embodiment of the invention, a method is provided for coating an optical fiber to reduce microbend losses and polarization mode dispersion (PMD). The method includes applying a primary layer to the optical fiber, wherein the optical fiber comprises a core region surrounded by a cladding region. The method includes applying a secondary layer to the primary layer, and curing the primary and secondary layers, wherein the cured primary layer adheres to the cladding region with a minimum pullout adhesion of 6 N/cm, and the cured secondary layer has an in situ modulus of about 700 MPa to about 1200 MPa at room temperature. | 08-04-2011 |
20110170829 | CONNECTOR COVER FOR OUTSIDE PLANT APPLICATIONS - Certain embodiments of the invention may include apparatuses, systems, and methods for providing a connector cover for outside plant application. According to an example embodiment of the invention, a connector cover assembly is provided. The assembly can include an elongated hollow cylindrical cover having a closed first end, and open second end. The assembly includes a plug comprising an elastomeric material and having a plug first end, a plug second end, a bore extending through the plug from the plug first end to the plug second end, and a cover mating surface adjacent to the plug first end. The cover mating surface is operable to slidingly engage the cover, and the plug is operable to surround and slidingly engage optical fiber cordage extending through the bore. | 07-14-2011 |
20110159178 | SYSTEMS AND METHODS FOR PURGING UV CURING TUBES - Certain embodiments of the invention may include systems and methods curing a coated optical fiber. The method includes drawing the coated optical fiber through a gas chamber filled with a predetermined gas, drawing the fiber through a cure tube coupled to the gas chamber, and purging at least a portion of an inner surface of the cure tube with a purge gas as the coated optical fiber is drawn through the cure tube. | 06-30-2011 |
20110150404 | OPTICAL FIBER COATING WITH A COLOR CONCENTRATE HAVING SLICKNESS ADDITIVE - Certain embodiments of the invention may include systems and methods for coating an optical fiber. The method includes coating an optical fiber with a primary coating, preparing a secondary coating by selectively mixing a concentrate with an ultraviolet (UV) curable diluent coating, wherein the concentrate comprises predetermined amounts of a color agent and a release agent, and applying the secondary coating to the optical fiber and primary coating. | 06-23-2011 |
20110129190 | Techniques for Manipulating Crosstalk in Multicore Fibers - 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. | 06-02-2011 |
20110110619 | TUNABLE DISPERSION COMPENSATOR WITH MINIMUM DIFFERENTIAL GROUP DELAY - In a method and system for providing dispersion compensation in an optical system, there is coupled into the optical system at least one pathway into which there is connected a tunable chirped fiber Bragg grating, each such grating providing a respective tunable amount of dispersion. At least one respective DGD element is connected into the respective pathway for each such grating. The set of all such respective DGD elements in a given pathway introduces a bias differential group delay DGD | 05-12-2011 |
20110097048 | Techniques for Manufacturing Birefringent Optical Fiber - In a technique for fabricating a birefringent optical fiber, a preform rod is fabricated having a longitudinal axis, an outer peripheral surface, and a selected refractive index variation. At least one longitudinal groove is cut into the preform rod through its outer peripheral surface, wherein the at least one longitudinal groove has a cross sectional area equal to that of a respective birefringence-inducing stress element to be loaded into the groove, such that when the stress element is loaded into the groove, a portion of the stress element protrudes outside of the circumference of the preform. A respective birefringence-inducing stress element is loaded into the at least one longitudinal groove. A preform assembly is created by positioning the loaded preform rod within an overcladding tube. The preform assembly is drawn into optical fiber. | 04-28-2011 |
20110067451 | Method of Fabricating Optical Fiber Using An Isothermal, Low Pressure Plasma Deposition Technique - An isothermal, low pressure-based process of depositing material within a substrate has been developed and results in creating an extremely narrow reaction zone within which a more uniform and efficient deposition will occur. Sets of isothermal plasma operating conditions have been found that create a narrow deposition zone, assuring that the deposited material is clear glass rather than soot particles. The chemical delivery system, in one arrangement, utilizes rods of solid phase source material (which may otherwise be difficult to obtain in gaseous form). The operating conditions are selected such that the hot plasma does not transfer a substantial amount of heat to the substrate tube, where the presence of such heat has been found to result in vaporizing the reactant material (creating soot) and developing hot spots. | 03-24-2011 |
20110058769 | All-Fiber Module for Femtosecond Pulse Compression And Supercontinuum Generation - An all-fiber optical pulse compression arrangement comprises a concatenated arrangement of a section of input fiber (e.g., a single mode fiber), a graded-index (GRIN) fiber lens and a section of pulse-compressing fiber (e.g., LMA fiber). The GRIN fiber lens is used to provide mode matching between the input fiber (supporting the propagation of chirped optical pulses) and the pulse-compressing fiber, with efficient pulse compression occurring along the length of the LMA fiber. The dispersion and length of the LMA fiber section are selected to provide the desired degree of pulse compression; for example, capable of reconstituting a femtosecond pulse as is used in supercontinuum generation systems. | 03-10-2011 |
20110052128 | Optical Fiber Preform With Improved Air/Glass Interface Structure - An optical fiber preform comprising a plurality of longitudinal air holes is subjected to a thermal treatment (i.e., heating), coupled with the application of a compressive force on either end of the heated preform to compress the entire preform structure a predetermined amount. The thermal compression treatment has been found to smooth any roughened glass surfaces and heal microcracks that may have formed during the preform fabrication process, essentially “knitting” the glass material back together and forming a preform of improved quality over the prior art microstructured preforms. | 03-03-2011 |
20100303402 | Phase-Engineered Fibers for Use in Generating Cylindrical Vector Beams - A phase-engineered fiber is described for generating a cylindrically polarized beam. The fiber includes a core region, a ring region surrounding the core region, and an outer cladding region surrounding the ring region. The fiber regions are configured to cause the fiber to have a refractive index step proximate to the peak amplitude value of the mode intensity profile of an LP | 12-02-2010 |
20100278486 | Fiber Based Laser Combiners - An all-fiber combiner device is described for combining multiple high power inputs, such as high power laser inputs. The device includes a first tapered fiber section made from fibers that allow for efficient size reduction of the optical signals. The output of the first tapered fiber section may then be coupled to a multimode output fiber for delivery of the combined power beam. Alternately, the first tapered section can be coupled to a second, multimode, tapered section, which provides further size reduction of the core for splicing into a final output fiber, while adding cladding to the main fiber. | 11-04-2010 |
20100266284 | Method and Apparatus Using Distributed Raman Amplification and Remote Pumping In Bidirectional Optical Communication Networks - A bidirectional optical communications network comprises an optical transmission fiber for carrying a downstream signal at a first wavelength and a multiplicity of upstream signals at a second, different wavelength. The fiber is characterized by distributed Raman gain over at least an extended portion of its length. A first terminal, optically coupled to one end of the fiber, includes a first transmitter for generating the downstream signal, a first receiver for detecting the upstream signals, and at least one pump source for generating pump light that provides Raman amplification to either the downstream signal or the upstream signal or both. A multiplicity of second terminals, optically coupled to another end of the fiber, each includes a second transmitter for generating one of the upstream signals, and a second receiver for detecting a downstream sub-signal. A passive optical node is configured to (i) split the downstream signal into a multiplicity of downstream sub-signals each propagating at the first wavelength to a separate one of the second terminals and (ii) to combine each of the upstream signals from each of the second terminals onto the fiber for transmission to the first terminal. In another embodiment, the network is a GPON compatible with current ITU standards. | 10-21-2010 |
20100220969 | Fiber Optic Cable Pulling Strain Relief - A strain relief for distributing strain along an outer surface of an optical fiber cable is disclosed. The strain relief is shaped to surround and tangentially grip the cable via friction between the outer surface of the cable and an inner surface of the strain relief. The strain relief also includes a pulling eye to protect the cable (and a connector) from pulling force (i.e. strain), water and dust. The strain relief is relatively small, low cost and easy to use. | 09-02-2010 |
20100080521 | OPTICAL FIBER WITH WATER-BLOCKING - Polymer-coated transmission media having water-blocking material embedded in the outer surface of the transmission media prevents water penetration into the transmission media and reduces the overall diameter of a cable made from the transmission media by eliminating a water-blocking tape layer in the cable. The outer surface of the transmission media is a polymer whose outer surface is embedded with a water-blocking material. The water-blocking material is applied before the polymer is cured. The transmission media may be any known type of optical media, which guides a light within the optical media. In various embodiments, optical fibers, buffered optical fibers and fiber ribbons are used as the transmission media. | 04-01-2010 |
20090290841 | Reduced Bend Sensitivity and Catastrophic Bend Loss In Single Mode Optical Fibers and Method of Making Same - An optical fiber that is relatively insensitive to bend loss and alleviates the problem of catastrophic bend loss comprises a core region and a cladding region configured to support and guide the propagation of light in a fundamental transverse mode. The cladding region includes (i) an outer cladding region, (ii) an annular pedestal (or ring) region, (iii) an annular inner trench region, and (iv) an annular outer trench region. The pedestal region and the outer cladding region each have a refractive index relatively close to that of the outer cladding region. In order to suppress HOMs the pedestal region is configured to resonantly couple at least one (unwanted) transverse mode of the core region (other than the fundamental mode) to at least one transverse mode of the pedestal region. In a preferred embodiment, the fiber is configured so that, at a signal wavelength of approximately 1550 nm, its bend loss is no more than about 0.1 dB/turn at bend radius of 5 mm and is no more than about 0.02 dB/turn at a bend radius of 10 mm. In addition, in one embodiment, the core region also includes an inner core region and an annular outer core (or shelf) region surrounding the inner core region. The outer core region extends radially a distance of less than 9 μm from the fiber axis. In another embodiment, the inner trench region includes an annular inner portion and an annular outer (or step) portion surrounding said inner portion. The refractive index of the step portion is greater than that of the inner portion. In a preferred embodiment, both of the foregoing features of the core region and the inner trench region are incorporated in the fiber. Also described are multi-tube fabrication techniques for making such fibers. | 11-26-2009 |
20090262779 | Multi-Core Fiber Grating Sensor - A twin core fiber for sensor applications is developed. It is particularly useful in de-coupling the strain and temperature and thus obtaining both measurement parameters at the same time and location. It is also particularly useful for measuring the temperature in a high humidity environment. The twin core fiber has two cores and each of the cores having a different dopant regime. Also, each of the cores includes a grating having substantially the same grating period. | 10-22-2009 |
20090257711 | Systems and Techniques for Generating Bessel Beams - A technique is described for generating a Bessel beam. An input optical fiber is provided that supports propagation in the fundamental mode. The input fiber is connected to a fiber mode converting device that provides phase matching, at a predetermined excitation wavelength, between the fundamental mode and a selected azimuthally symmetric higher-order mode. As an input to the fiber mode converting device, a coherent light beam is fed through the input optical fiber to provide a fundamental mode input at the excitation wavelength. The fiber mode converting device resonantly excites the selected azimuthally symmetric mode. The azimuthally symmetric mode is provided as a beam output from an endface of the fiber mode converting device to approximate a Bessel beam. | 10-15-2009 |
20090230580 | Systems and Techniques for Reducing Group Delay Ripple in a Dispersion Compensating Grating - A technique is described for reducing group delay ripple in a fiber dispersion compensation grating. The grating is mounted into a trimming setup that includes a trimming device and a scanning assembly for causing a region of the grating to be scanned along its length by the trimming device output. The grating is sensitive to the trimming device output, such that exposure to the trimming device output causes a change in the effective refractive index of the scanned region, the amount of change varying as a function of scanning velocity. A region of the grating to be trimmed is selected, and a scanning velocity profile is programmed into the scanning assembly that is calculated to modify the effective refractive index of the selected grating region along its length so as to smooth out group delay ripple in the selected grating region. | 09-17-2009 |