Abstract: Disclosed herein is a method for measuring temperature via distributed temperature sensing comprising transmitting light through a fiber optic cable; detecting backscattered light in the fiber optic cable, wherein the backscattered light comprises an anti-Stokes band and a Stokes band; calculating a ratio between an intensity of the anti-Stokes band and an intensity of the Stokes band; and using the calculated ratio to determine a temperature being sensed in the fiber optic cable; wherein the fiber optic cable comprises, from the center to the periphery; a central core having a refractive index that decreases progressively from a center of the central core to an edge of the core, wherein the refractive index follows an alpha profile; wherein a bandwidth-length product of the multimode optical fiber has a value greater than 2000 MHz-km at 1550 nm.

Abstract: Disclosed herein is an all-fiber, easy to use, wavelength tunable, ultrafast laser based on soliton self-frequency-shifting in an Er-doped polarization-maintaining very large mode area (PM VLMA) fiber. The ultrafast laser system may include an all polarization-maintaining (PM) fiber mode-locked seed laser with a pre-amplifier; a Raman laser including a cascaded Raman resonator and an ytterbium (Yb) fiber laser cavity; an amplifier core-pumped by the Raman laser, the amplifier including an erbium (Er) doped polarization maintaining very large mode area (PM Er VLMA) optical fiber and a passive PM VLMA fiber following the PM Er VLMA, the passive PM VLMA for supporting a spectral shift to a longer wavelength.

Abstract: A fiber-based optical amplifying system for use with a multi-wavelength input optical signal operating over a predetermined bandwidth is specifically configured to eliminate the need for a separate gain-flattening filter, improving the power conversion efficiency (PCE) of the system. Both a distributed Raman amplifier (DRA) and an erbium-doped fiber amplifier (EDFA) are used, where the DRA component is configured to use a pump beam with at a power level no greater than 200 mW. The EDFA is configured to exhibit a gain profile the complements that of the DRA, while also providing amplification that is no less than 10dB at any wavelength within the system bandwidth. With these parameters, the combination of the DRA and EDFA is able to maintain an output gain deviation of less than about 2 dB.

Abstract: Disclosed herein is a method comprising injecting light of a first wavelength ?1 into a wavelength division multiplexer; injecting light of a second wavelength ?2 into the wavelength division multiplexer; combining the light of the first wavelength ?1 and the light of the second wavelength ?2 in the wavelength division multiplexer to produce light of a third wavelength ?3; and reflecting the light of the third wavelength ?3 in a dual-Brillouin peak optical fiber that is in communication with the wavelength divisional multiplexer; wherein the dual-Brillouin peak optical fiber has at least two Brillouin peaks, such that an amplitude A1 of at least one of said Brillouin peaks is within 50% to 150% of an amplitude A2 of another Brillouin peak 0.5A2?A1?1.5A2; wherein the dual-Brillouin peak optical fiber generates a Brillouin dynamic grating that reflects an improved back-reflected Brillouin signal of the combined light.

Abstract: A system for installing an optical fiber cable in a building hallway or living unit includes an elongated cylinder for containing an adhesive, and a continuous length of an optical fiber cable embedded in the adhesive in a configuration that avoids kinks or knots in the cable. An elongated nozzle is fixed at a first end of the cylinder for depositing the adhesive and the cable from an open tip of the nozzle, along a desired routing path in the hallway or living unit. An applicator assembly is constructed and arranged for receiving the cylinder, and for applying a dispensing force at a second end of the cylinder opposite the first end so as to urge the adhesive and the cable out of the open tip of the nozzle.

Abstract: Before pulling a leading end of a fiber optic cable through a duct in order to splice the cable fibers to other fibers located at a far end of the duct, the outer jacket of the cable and elements surrounding the cable fibers are removed to expose the fibers. The exposed fibers are prepared by (a) removing coatings on the fibers, (b) cleaving the ends of the fibers, and (c) placing the cleaved fibers into one or more protective covers. A cable grip or sock is dimensioned and formed to envelop the leading end of the cable including the protective covers, up to and including the outer jacket. The grip together with the cable are pulled through the duct, and the grip and the protective covers are removed at the far end of the duct to expose the cleaved fibers for splicing to the other fibers at the far end.

Abstract: A fiber-optic cable having optical fibers that are arranged as a rollable ribbon. Water-swellable material (e.g., superabsorbent liquid, superabsorbent powder, superabsorbent adhesive, etc.) is applied directly to the rollable ribbon, thereby eliminating the need to incorporate conventional water-absorbing yarns, tapes, or other such similar materials. The rollable ribbon is surrounded by a tube, with a dielectric strength member positioned external to the tube and substantially parallel to the tube. A jacket, with a ripcord along a substantial length of the jacket, surrounds the tube. Also taught is a process for manufacturing a rollable-ribbon fiber-optic cable, in which a water-swellable material is applied directly to the rollable ribbon, thereby eliminating the need to incorporate conventional water-absorbing yarns, tapes, or other such similar materials.

Abstract: An optical fiber comprising a core, a cladding disposed about the core, and a primary coating disposed about the cladding. The primary coating is cured during draw to at least eighty-five percent (85%) of the primary coating's fully cured primary-coating in situ modulus (P-ISM) value.

Abstract: An apparatus for fabricating a hollow core optical fiber with a controllable core region (in terms of diameter) is based upon regulating conditions (gas flow, volume, and/or temperature) within the hollow core region during the fiber draw process. The introduction of a gas, or any change in volume or temperature of the hollow core region, allows for the diameter of the hollow core region to self-regulate as a multistructured core rod (MCR) is drawn down into the final hollow core optical fiber structure. This self-regulation provides a core region having a diameter that selected and then stabilized for the duration of the draw process. The inventive apparatus is also useful in controlling the diameter of any selected hollow region of an MCR including, but not limited to, shunts and corner capillaries disposed around the core region.

Abstract: A photoinduced refractive index-changing material is coupled directly to both a first port and a second port. An optical interconnect structure (for optically coupling the first port to the second port) is formable in the photoinduced refractive index-changing material by selectively exposing a portion of the photoinduced refractive index-changing material. The selective exposure induces a refractive index change in the photoinduced refractive index-changing material. The change in refractive index provides the waveguiding properties of the optical interconnect structure.

Abstract: Bismuth (Bi) doped optical fibers (BiDF) and Bi-doped fiber amplifiers (BiDFA) are shown and described. The BiDF comprises a gain band and an auxiliary band. The gain band has a first center wavelength (?1) and a first six decibel (6 dB) gain bandwidth. The auxiliary band has a second center wavelength (?2), with ?2>?1. The system further comprises a signal source and a pump source that are optically coupled to the BiDF. The signal source provides an optical signal at ?1, while the pump source provides pump light at a pump wavelength (?3).

Abstract: Disclosed herein is a coating composition comprising a silsesquioxane component having one or more reactive functional groups that render it curable using ultraviolet radiation; where the one or more reactive functional groups are selected from the group consisting of an acrylate, a vinyl ether, or an epoxy; and optionally, a co-reactive non-silsesquioxane monomer and/or an oligomer having one or more reactive functional groups that are curable using ultraviolet radiation and are selected from the group consisting of free radically curable acrylates, cationically curable epoxies, and cationically curable vinyl ethers; where the coating composition is disposed and cured on an optical article; where the optical article is at least one of an optical fiber or an optical planar waveguide; and where the average functionality of the composition is greater than one.

Abstract: An optical fiber comprising a core, a cladding disposed about the core, and a primary coating disposed about the cladding. The primary coating is cured during draw to at least eighty-five percent (85%) of the primary coating's fully cured primary-coating in situ modulus (P-ISM) value.

Abstract: The selection of starting materials used in the process of forming an MCR is controlled to specifically define the physical properties of the core tube and/or the capillary tubes in the local vicinity of the core tube. The physical properties are considered to include, but are not limited to, the diameter of a given tube/capillary, its wall thickness, and its geometry (e.g., circular, non-circular). A goal is to select starting materials with physical properties that yield a final hollow core optical fiber with a “uniform” core region (for the purposes of the present invention, a “uniform” core region is one where the struts of cladding periodic array surrounding the central core are uniform in length and thickness (with the nodes between the struts thus being uniformly spaced apart), which yields a core wall of essentially uniform thickness and circularity.

Abstract: An optically transparent protective coating is described that remains stable at elevated temperatures associated with optical fiber-based sensor applications and is sufficiently transparent to allow for conventional fiber Bragg gratings (FBGs) to be formed by directly writing through the coating. In particular, vinyl group-containing silicone polymers have been found to provide the UV transparency required for a write-through coating (WTC) and promising mechanical properties for protecting the optical fibers, while also being able to withstand elevated temperatures for extended periods of time.

Abstract: A technique for fabricating a hollow core optical fiber with a controllable core region (in terms of diameter) is based upon regulating conditions (gas flow, volume, and/or temperature) within the hollow core region during the fiber draw process. The introduction of a gas, or any change in volume or temperature of the hollow core region, allows for the diameter of the hollow core region to self-regulate as a multistructured core rod (MCR) is drawn down into the final hollow core optical fiber structure. This self-regulation provides a core region having a diameter that selected and then stabilized for the duration of the draw process. The inventive process is also useful in controlling the diameter of any selected hollow region of an MCR including, but not limited to, shunts and corner capillaries disposed around the core region.

Abstract: An extended length of optical fiber having an offset core with an inscribed Bragg grating is used a distributed sensor in combination with an optical frequency domain reflectometer (OFDR) to enable measurement small-scale (e.g., sub-millimeter) contortions and forces as applied to the fiber. The offset core may be disposed in a spiral configuration around the central axis of the optical fiber to improve the spatial resolution of the measurement. A reference surface exhibit a predetermined texture (in the form of a series of corrugations, for example, that may be periodic or aperiodic, as long as known a priori) is disposed adjacent to a longitudinal portion of the sensor fiber. The application of a force to the combination of the plate and the fiber creates a local strain in the grating formed along the offset core of the fiber that results in a shift in the Bragg wavelength of the grating.

Abstract: A wavelength-swept optical source is based upon a combination of a coherent source of ultra-short optical pulses, doped fiber amplifier, and specialized dispersive optical medium to create time-stretched pulses. The pulses are broadened to have a spectral bandwidth that covers a wavelength range of interest for a particular wavelength sweeping application and are thereafter subjected to time-stretching within the dispersive optical medium so as to sufficiently separate in time a number of wavelength components within each pulse.

Abstract: An all-fiber supercontinuum (SC) optical source utilizes a combination of a seed pulse supply of short-duration optical pulses with a highly non-linear optical medium in the form of two or more concatenated sections of highly non-linear optical fiber (HNLF) of different dispersion values and lengths. The two or more sections of HNLF are configured to include at least one section that exhibits a positive dispersion value and one section that exhibits a negative dispersion value. Non-linear effects such as self-phase modulation (SPM), cross-phase modulation (XPM), Raman amplification, and the like, cause the seed pulses to broaden as they propagate through each section of HNLF, where the differences between the dispersion values, as well as the lengths of each fiber section, are particularly configured to create an SC output that is wide and smooth, exhibiting a stable intensity and high coherence level.

Abstract: An optical preform manufacturing process is disclosed in which an alkali dopant is deposited between an optical fiber core rod and an optical fiber cladding jacket. Depositing the alkali dopant between the core rod and the cladding jacket permits diffusion of the alkali dopants into the core during fiber draw when the core and the cladding are at their respective transition (or vitrification) temperatures. Introduction of the alkali dopants between the core rod and the cladding jacket also permits decoupling of the alkali doping process from one or more of other optical preform manufacturing processes. The optical preform manufacturing process can also include placing alkali dopants between an optical fiber inner cladding jacket and an optical fiber outer cladding jacket to reduce the glass viscosity during fiber draw.