275 results about "Buffer (optical fiber)" patented technology

The invention relates to optical fiber cables and, more specifically, to an optical fiber cable especially suited for blown installation or pushing installation in microducts of small diameter. An exemplary microcable for installation in small microducts has an outer sheath as buffer tube that holds a plurality of optical fibers without a layer of strength elements stranded around the outer sheath, which is made of one single thermoplastic material.

A buffered optical fiber arrangement that includes a buffer tube in which is provided optical fibers and a texturized yarn coated with a water-swellable material. The filament diameter of the yarn used in the present invention may be between about 5 microns and about 100 microns, more preferably between about 10 and about 60 microns, still more preferably between about 20 and about 40 microns. The linear density, or denier in grams per 9000 meters, of the base yarn may be between about 100 and 1000, more preferably between about 200 and 600, or still more preferably between about 250 and 350. The degree of decrease in length (the "degree of texturizing") between the perfectly straight filaments before texturizing and the texturized filament may be between 1 percent and 90 percent, more preferably between about 2 percent and 50 percent, or still more preferably between about 5 percent and 25 percent.

The present invention provides optical fiber communication cable assemblies useful for separating and conveying individual fibers from a multiple optical fiber cable to connectors in a protective manner. The optical fiber cable assembly is suitable for outdoor use and includes a (i) cable with multiple optical fibers; (ii) a furcation unit attached to the cable for directing individual optical fibers from the cable to furcation legs; and (iii) multiple furcation legs receiving at least one of the optical fibers. The furcation legs include (i) a buffer tube surrounding the optical fiber; (ii) strength members surrounding the buffer tube; and (iii) a jacket surrounding the strength members. The furcation legs typically exhibit a tensile rating of at least about 50 pounds (lbf), more typically 100 pounds (lbf) or more. Moreover, the furcation legs typically exhibit total shrinkage of less than about 2 percent when cycled from +23° C. to −40° C. to +70° C. to −40° C.

Disclosed is an optical fiber cable that includes optical fibers and a deformable coupling element enclosed within a buffer tube. The coupling element is formed from a deformable yet substantially incompressible material that is capable of releasably and intermittently coupling the optical fibers to the buffer tube in various orientations. The design of the coupling element layer permits coupling of the optical fibers to the buffer tube without the use of a compressive cushioning layer and yet permits localized movement the optical fibers relative to the buffer tube to account for disparate thermal expansion and to accommodate optical fiber placement.

Disclosed is an improved optical fiber that employs a novel coating system. When combined with a bend-insensitive glass fiber, the novel coating system according to the present invention yields an optical fiber having exceptionally low losses.The coating system features (i) a softer primary coating with excellent low-temperature characteristics to protect against microbending in any environment and in the toughest physical situations and, optionally, (ii) a colored secondary coating possessing enhanced color strength and vividness.The improved coating system provides optical fibers that are useful in buffer tubes and cables having relatively high filling coefficients and fiber counts.

The present invention relates to a novel coupling composition that is used within optical fiber cables to protect optical fibers and to couple the optical fibers and the surrounding buffer tube casing. The present invention also relates to optical fiber cables that use the novel coupling composition.

A cable containing at least one optical fiber within a tube, a space between the optical fiber and the tube and a filling material at least partially filling the space. The filling material contains thermoplastic polymeric molecules which have bonded to form a three-dimensional network substantially throughout said filling material.

Disclosed is an optical fiber cable that includes optical fibers and a deformable coupling element enclosed within a buffer tube. The coupling element is formed from a deformable yet substantially incompressible material that is capable of releasably and intermittently coupling the optical fibers to the buffer tube in various orientations. The design of the coupling element layer permits coupling of the optical fibers to the buffer tube without the use of a compressive cushioning layer and yet permits localized movement the optical fibers relative to the buffer tube to account for disparate thermal expansion and to accommodate optical fiber placement.

In a buffer tube arrangement, discrete domains of adhesive material provide adhesive coupling of a water-swellable element and an optical fiber bundle that includes a plurality of optical fibers.

An optical cable comprises a buffered optical fiber which is arranged within a buffer tube. The buffer tube is extruded around the buffered optical fiber such that a small gap, preferably in a range between about 40 μm and about 100 μm, is formed between the buffered optical fiber and the buffer tube. A layer of strength member elements is disposed around the buffer tube. A cable jacket is extruded around the strength member elements wherein the strength member elements are bonded to the cable jacket.

Consistent with the present disclosure, an encoder circuit is provided at a transmit side of an optical fiber link that maps an input sequence of bits of fixed length k a sequence of symbols of a codeword of length n, such that the symbols of the codeword define a predetermined transmission probability distribution. Preferably, each symbol of the codeword is generated during a corresponding clock cycle, such that after n clock cycles, a complete codeword corresponding to the input bit sequence is output. On a receive end of the link, a decoder is provided that outputs the k-bit sequence every n clock cycles. Accordingly, buffers need not be provided at the output of the encoder and the input of the decoder, such that processing of the input sequence, codewords, and output sequence may be achieved efficiently without large buffers and complicated circuitry. Moreover, the input sequence, with any binary alphabet may be matched to a desired output distribution with any arbitrary alphabet. Accordingly, probabilistic constellation shaping may be achieved over constellations of arbitrary size. In addition, relatively long codewords, may be encoded and decoded with the apparatus and method disclosed herein. Accordingly, for a fixed SNR a higher SE (more bits per symbol) can be achieved. Alternatively, for a fixed SE, a lower SNR may be sufficient. Moreover, the resulting SE may be finely tailored to a particular optical link SNR to provide data transmission rates that are higher than the low order modulation formats that would otherwise be employed for optical signals carried by such links.

A fiber optic cable is that includes at least one optical fiber and a protective layer generally disposed about the optical fiber. A cable jacket surrounds an outer surface of the protective layer, and a control layer is interposed between a portion of the protective layer and a portion of the cable jacket. The control layer includes one or more apertures extending therethrough, thereby creating a predetermined bond between the protective layer and the cable jacket. By way of example, the protective layer is an armor layer, buffer tube, or other suitable cable component where a predetermined bond to the cable jacket is desired so the craft can easily remove a portion of the cable jacket. The plurality of apertures can have any suitable size, shape, and / or arrangement for influencing the desired bond strength. A method of manufacturing the fiber optic cable is also disclosed.

According to at least one exemplary embodiment a ferrule, comprises: (i) a bore extending from a rear of the ferrule to a front of the ferrule, wherein the bore is sized to receive an optical fiber and a buffer layer at one end face of the ferrule; and (ii) an end stop sized to engage the buffer layer and to contain the optical fiber within said ferrule. In some embodiments the ferrule includes an optical fiber situated within the bore.

At least one buffered optical fiber, and methods for manufacturing the same, including an optical fiber and a buffer layer. The buffer layer generally surrounds the optical fiber and has a low-shrink characteristic that preserves optical performance during, for example, temperature variations. In other embodiments, the at least one buffered optical fiber may be a fiber optic ribbon.

An optical fiber comprising: (i) a multi-mode silica based glass core, said core having a 80-300 μm diameter and an index of refraction n1; (ii) a cladding surrounding the core, said cladding having a thickness ≦20 μm and index of refraction index of refraction n2<n1, the cladding comprising (a) fluorine doped silica with relative index of refraction delta <0, or (b) a polymer with relative index of refraction delta <0; (iii) a protective coating, the protective coating having a Young's modulus greater than 700 MPa, a thickness ≦15 μm, and an index of refraction index of refraction n3>n2; and (iv) a permanent buffer.

In one of the embodiments there is disclosed a self healing optical fiber cable assembly comprising an elongated optical fiber core having a cladding layer, a buffer layer, a sealing layer that seals any microcracks or defects in the buffer layer, the cladding layer, and the optical fiber core, and, an outer protection layer, wherein an end of the outer layer is connected to a strain relief device to provide expansion protection to the cable assembly and to minimize strain on the cable assembly, and further wherein an end of the strain relief device is connected to an optical fiber module. The cable assembly may further comprise a constraining layer and / or a strengthening layer. There is also disclosed a method of making a self healing optical fiber cable assembly.

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.

The invention relates to a cascaded Mach-Zehnder interferometer based reconfigurable comb filter and a preparation method thereof. The filter comprises a planar lightwave circuit (PLC) chip, a first optical fiber array and a second optical fiber array, wherein the PLC chip comprises a silicon substrate, a silicon dioxide buffer layer is arranged on the silicon substrate, a waveguide is arranged on the silicon dioxide buffer layer, a coverage layer is arranged on the waveguide, and the waveguide comprises an input-stage Y branch, a first-length fixing arm, a second-length fixing arm, a first opening arm, a second opening arm, a third opening arm, a fourth opening arm, a first-stage 3dB coupler, a second-stage 3dB coupler and an output-stage 3dB coupler. The method comprises the steps of preparing the buffer layer and the waveguide on the silicon substrate so as to obtain a PLC chip portion, slicing and grinding the PLC chip portion, then, coupling the PLC chip portion with the optical fiber arrays, and finally, connecting corresponding optical fibers. The filter and the method have the advantages of reconfigurability, fine adjustable phase, flat-crest filtering and low-nonlinearity output.

Described are cable designs adapted for aerial installations wherein the cable comprises a bundle of multifiber tight buffer encasement units, with a conformal thin skin containment layer surrounding the bundle. The multifiber tight buffer encasement units have 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 thin skin containment layer provides cable integrity with a minimum of added size and weight. The thin skin containment layer encasement is encased in an outer protective jacket.

A buffered optical fiber having an excellent pistoning characteristic compared with a conventional one and a manufacturing method thereof are provided. The buffered optical fiber of the present invention is composed of an optical fiber with a primary coating layer and a secondary coating layer provided on a circumference of a glass optical fiber and a tertiary coating layer having thermoplastic polyester elastomer as the main ingredient provided on a circumference of the optical fiber and is characterized in that an outer diameter of the primary coating layer is 180 to 200 μm, an outer diameter of the secondary coating layer is 350 to 450 μm and the product of a thickness of the secondary coating layer of the optical fiber and a force of pulling out the glass optical fiber from the optical fiber is 720 N / mm·μm or more.

The invention provides an ultrahigh-speed burst mode clock restoring circuit based on a gate-control oscillator, comprising the gate-control oscillator, four frequency dividers, a frequency-discrimination device, a charge pump, a low-pass filter, an interior clock buffer and a semi-velocity data restoring circuit. The ultrahigh-speed burst mode clock restoring circuit is characterized in that an output clock of the gate-control oscillator can restore a clock signal from input data of any phases within a plurality of bit times when data turn over under traction action of the input data, wherein the phase of the clock signal is aligned with the phase of the input data; the four frequency dividers, the frequency-discrimination device, the charge pump, the low-pass filter and the interior clock buffer are used for analyzing relation of output lock signal frequency and reference frequency and providing a control signal for the gate-control oscillator, and the semi-velocity data restoring circuit resets the data according to the restored clock signal to generate a restored data signal. The ultrahigh-speed burst mode clock restoring circuit disclosed by the invention is suitable for an optical fiber communication system, and in particular relates to a burst mode optical communication system taking a ten-gigabit Ethernet passive optical network technology as representation.

Furcation assemblies (100) for furcating a fiber optic drop cable (10) are disclosed. An example furcation assembly includes a furcation member (110) having an elongate furcation body (112) defining an axial channel (130) with a front section (132). The channel front section is configured to accommodate and be secured to either a buffer tube (30) of a buffered drop cable or a protective cover (20) of an unbuffered drop cable. A flexible guide (150) is secured to the furcation member back end. A flexible protection member (180) slidably fits within the guide back end and is telescopically adjustable relative thereto. To create a cable assembly (200) using the furcation assembly, the furcation member is secured to the drop cable so that the optical fiber (40) carried thereby is passed through the furcation member, through the guide and through the protection member to form an exposed fiber section. The fiber end (41) of the exposed fiber section is then connectorized with a connector (200) and the protection member is slid over the exposed fiber portion and is connected to the connector back end (214). Furcation assemblies and methods for handling multiple fibers are also disclosed.

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.

Disclosed is a small-diameter polarization maintaining optical fiber, which relates to the field of special optical fibers. The small-diameter polarization maintaining optical fiber comprises a quartz optical fiber (5); the periphery thereof is provided with an inner coating (6) and an outer coating (8); the interior of the quartz optical fiber (5) is provided with an optical fiber core layer (1) and a quartz cladding (2); two stress zones (4) are arranged between the optical fiber core layer (1) and the quartz cladding (2); a buffer coating (7) is arranged between the inner coating (6) and the outer coating (8); the periphery of each stress zone (4) is provided with a buffer layer (3) which is concentric with the stress zone (4); when a working wavelength of a small-diameter polarization maintaining optical fiber is 1310 nm, the attenuation thereof reaches less than 0.5 dB / km, and the crosstalk reaches −35 dB / km; and when the working wavelength of the small-diameter polarization maintaining optical fiber is 1550 nm, the attenuation thereof reaches less than 0.4 dB / km, and the crosstalk reaches −30 dB / km. The optical fiber not only has excellent stability characteristics of attenuation and crosstalk, but also has the excellent stability characteristic of long-term operation, and can provide a better optical fiber ring for research on a high-precision optical fiber gyroscope, thereby laying the foundation for the development directions of miniaturization and high precision of the optical fiber gyroscope.

The invention discloses a feeder type optical power composite cable for 4G (the fourth generation). The feeder type optical power composite cable comprises a cable outer sheath, wherein the cable outer sheath comprises a taped covering, an aluminium soldering wrapping laminae is arranged outside the taped covering, an outer sheath layer is arranged outside the aluminium soldering wrapping laminae, two sets of electrical units, two sets of optical units and a filler are arranged inside the taped covering. The electrical units and the optical units are arranged at intervals by surrounding the filler. The optical units adopt the optical fiber G657, and a buffer layer structure is sleeved tightly outside the optical units, so that the bending property of the optical fiber can be ensured, and the mechanical strength of the optical fiber is enhanced. The insulation requirements for electric wires and cables with nominal voltage of 450V / 750V for electrical units can be met, and PVC (Poly Vinyl Chloride) or XLPE (Cross Linked Polyethylene) is adopted as the insulating layer of the electrical units. The feeder type optical power composite cable has the advantages that the construction cost of a base station is effectively reduced, the construction is rapid, and the stability is good.

The present invention is directed to a novel construction of buffer tubes for fiber optic cables which offers a way to access the optical fibers inside a buffer tube while reducing the risk of damaging the fibers, as sometimes occurs when cutting the outer layer of the buffer tube. A buffer tube for use in a fiber optic cable of the present invention comprises a tube having a tube wall, the wall having an inside and outside surface, wherein an inner portion of tube wall, nearest the inside surface, is made of a material having a higher notch-sensitivity than an outer portion of the tube wall nearest the outside surface.

The present invention features methods and devices for microorganisms through detecting Mie light scattering from immunoagglutinated beads. The methods feature providing a first bead suspension with antibody specific for the microorganism conjugated to beads; mixing the first bead suspension with a sample to form a first mixture; irradiating the first mixture with first incident light; detecting forward light scattering at a first angle with respect to the first incident light, where the first angle being between about 30 to 60 degrees; determining l from the light scattering; providing a second bead suspension with no antibody and simultaneously measuring l0 in a similar manner; comparing l with l0. All light scattering measurements may be made in a two-well slide or a Y-channel microfluidic device. Samples, for example food samples (e.g., vegetable samples), may be prepared in a variety of ways. A vegetable sample may be chopped up and added to a buffer. In some embodiments, the sample is then filtered with a common cloth or tissue component. The present invention also features devices (or apparatuses) for detecting a microorganism in a sample. The apparatuses may be a large-scale device or a small-scale device. The large-scale device may consist of a portable spectrometer, light source, optical fibers, and adjustable positioning stages, in addition to, for example, a two-well slide or a microfluidic device. The small-scale device is made portable by using, for example, light-emitting diodes, avalanche photodiodes, an op-amp circuit, Arduino microcontroller board, an LCD display, and small batteries, in addition to, for example, a two-well slide or a microfluidic device. Therefore, the invention is adaptable for detecting microorganisms in vegetable sample preparations. Still further, the invention may be operated on a small-scale, for example, for use by workers in agriculture fields or food factories.