59results about "Optical fibre with multilayer core/cladding" patented technology

A multicore optical fiber may include a common cladding comprising a radius R4 defining a glass portion of the optical fiber and having a cladding relative refractive index Δ4. At least two waveguides may extend through the common cladding. Each waveguide may include a core region, an inner cladding region, and a depressed cladding region. Each core region may include a maximum relative refractive index Δ1max. Each inner cladding region may include a relative refractive index Δ2. Each depressed cladding region may include a minimum relative refractive index Δ3min and a trench volume from 20-45%µm2 such that Δ1max>Δ2>Δ3min, and Δ4>Δ3min. A cable cutoff wavelength of each waveguide is ≤1150 nm. The co-propagating and counter-propagating inter-waveguide cross talk between each waveguide and a nearest waveguide is <-35 dB at 1310 nm and <-20 dB at 1550 nm for application lengths of 20 m. A mode field diameter of each waveguide is 8.2-9.0 µm at 1310 nm.

The application relates to a hollow optical fiber and an optical cable, the hollow optical fiber comprising a cladding region and a core region; the cladding region comprising, from outside to inside, an outer cladding and an anti-resonance layer; the core region comprising a region surrounded by the boundary of the anti-resonance layer and the outer cladding; wherein the anti-resonance layer comprises a plurality of rotationally symmetric distributed nested units, the nested units comprising a first nested ring and a second nested ring nested in the first nested ring, the first nested ring being connected to the inner wall of the outer cladding with a first arc length, and the second nested ring being connected to the inner wall of the first nested ring at the position where the first nested ring is connected to the inner wall of the outer cladding with a second arc length. The application can solve the problem of poor stability of the nested ring structure of the hollow optical fiber in the prior art, which is easily deformed by external stress.

The application discloses a silicon-coated nested single-polarization single-mode hollow optical fiber, which comprises an outer structure tube and a plurality of double-layer anti-resonance cladding tubes, wherein each double-layer anti-resonance cladding tube is arranged at equal intervals along the inner wall of the outer structure tube, and each double-layer anti-resonance cladding tube comprises an inner layer cladding and an outer layer cladding which are mutually circumscribed; the inner layer cladding is a coaxially nested anti-resonance tube, which comprises a peripheral cladding tube with a large aperture and an internal cladding tube with a small aperture which is coaxially nested in the hole of the peripheral cladding tube, the peripheral cladding tube and the internal cladding tube are mutually inscribed, and the inscribed point and the circumscribed point are coincident; and the outer layer cladding is an anti-resonance tube and is mutually inscribed with the outer structure tube. The double-layer anti-resonance cladding tube can realize high-quality single-mode single-polarization transmission with a continuous bandwidth of 60 nm near the central wavelength, the average transmission loss is low, and the near-zero flat dispersion characteristic is possessed.

A method for producing a fiber Bragg grating element includes: a preparation step of preparing an optical fiber having a layer structure including a core and one or more outer peripheral layers that is made of a transparent optical material and that includes a cladding surrounding the core and having a refractive index less than a refractive index of the core, at least one outer peripheral layer of the one or more outer peripheral layers containing a photosensitive material; a stretching step of heating and stretching the optical fiber to form a narrow-diameter region having a reduced diameter and a pair of transition regions at both ends of the narrow-diameter region, a diameter of which gradually increases continuously from the narrow-diameter region; and an exposure step of irradiating a part of the narrow-diameter region with light to cause a photoinduced refractive index change and to form a fiber Bragg grating in which a refractive index of the outer peripheral layer containing the photosensitive material periodically changes.

The application provides a thulium-doped optical fiber and a preparation method thereof. The thulium-doped optical fiber comprises: a fiber core composed of 12-40 concentric doped layers, including Tm 3+ doped layers and Nd 3+ doped layers, and Tm 3+ doped layers and Nd 3+ The doped layers are alternately distributed along the radial direction; a low-refractive-index step layer with a refractive index lower than that of the fiber core; a cladding layer; and a coating layer. The application can realize high-efficiency and high-beam-quality laser output of the thulium-doped optical fiber under high power and reduce front-end heating.

The present invention discloses a bending-insensitive high-bandwidth multimode optical fiber, including a core layer, an extension layer, an inner cladding, a sunken cladding, and an outer cladding disposed sequentially from inside to outside. The core layer has a parabolic refractive index profile, 1.9 to 2.2 of a distribution index and 0.9% to 1.2% of the maximum relative refractive index difference at a center. The extension layer has -0.03% to -0.02% of a relative refractive index difference. The inner cladding has 0.005% to 0.03% of the difference between the highest relative refractive index difference and the lowest relative refractive index difference and 0.5 µm to 4 µm of an unilateral radial width. The sunken cladding has 3 µm to 9 µm of an unilateral radial width and 0.7% to -0.4% of a relative refractive index difference. In the present invention, a waveguide structure and a doping system are rationally designed, optimizing the viscosity of the optical fiber, and reducing the sensitivity of the bandwidth of the optical fiber to the wavelength. Therefore, the optical fiber has a good bending resistance while having an ultra-high bandwidth performance.

The application provides a magnetic control flexible CO2 laser few-mode multi-core energy transmission optical fiber and a preparation method thereof. The magnetic control flexible CO2 laser few-mode multi-core energy transmission optical fiber has at least two independent laser transmission structures, a polymer cladding layer wrapped around the outer periphery of the laser transmission structure, and a magnetic outer cladding layer wrapped around the outer periphery of the polymer cladding layer, a single laser transmission channel outputs less than two modes of CO2 laser, and the adjustable controllability of the optical fiber output light field is realized, while the flexibility, robustness and actuation of the optical fiber are ensured. By controlling the fiber core diameter or the refractive index difference of the core cladding material, the single optical channel laser single-mode or few-mode output can be controlled, by controlling the number, position, distance and adding the inter-channel polymer of the optical fiber laser transmission channel, the optical crosstalk between channels can be reduced, the output light field of the optical fiber can be precisely adjusted, by controlling the magnetic particle doping amount, diameter and external magnetic field of the magnetic outer cladding layer, the movement and turning of the optical fiber can be controlled, and high-precision minimally invasive surgical medical operation is realized.

To provide an optical fiber that is suitable for reducing transmission loss and is highly manufacturable. [Solution] The optical fiber comprises a core made of silica glass and a cladding portion made of silica glass, surrounding the outer circumference of the core and having a refractive index lower than the maximum refractive index of the core. The core has a center core which has the highest average refractive index within the optical fiber, and the center core does not contain germanium as a dopant to increase the refractive index of the silica glass, and the relative refractive index difference Δclad between the refractive index of the cladding portion and the refractive index of the pure silica glass is 0% or more.

A method of forming an optical element is provided. The method includes producing silica-based soot particles using chemical vapor deposition, the silica-based soot particles having an average particle size of between about 0.05 μm and about 0.25 μm. The method also includes forming a soot compact from the silica-based soot particles and doping the soot compact with a halogen in a closed system by contacting the silica-based soot compact with a halogen-containing gas in the closed system at a temperature of less than about 1200° C.

A hollow core fiber is provided. The hollow core fiber includes at least one cleaved fiber end-face and a dielectric coating. The dielectric coating is formed by a passivation layer of dielectric that is applied to the at least one cleaved fiber end-face such that a portion of an interior surface that defines a hollow core of the hollow core fiber adjacent to the at least one cleaved fiber end-face is coated with the dielectric coating.

Provided is an optical combiner that can easily perform fusion processing of an input-side optical member and an output-side optical member. An optical combiner (40) includes an optical output portion (130) having a connection end surface (135) to which an optical input portion (110, 120) having a core (11, 21) is connected. The optical output portion (130) includes: a core (31, 33) that propagates light; and an outer cladding layer (34) that is located outside the core (33). The optical input portion (110, 120) is connected to the connection end surface (135) of the optical output portion (130) in such a manner that the core (11, 21) is optically coupled to the core (31, 33) of the optical output portion (130). An outer diameter (D1) of the outer cladding layer (34) on the connection end surface (135) of the optical output portion (130) is smaller than a diameter of a minimum containing circle (C1) of a cladding layer (22) of the optical input portion (120) that contains all of the optical input portion (120) on the connection end surface (135) of the optical output portion (130).

To provide a method for manufacturing an optical fiber capable of suppressing disconnection of an optical fiber and an optical fiber.SOLUTION: A method for manufacturing an optical fiber includes: melting an optical fiber base material and drawing a glass fiber; applying a resin composition to an outer periphery of the glass fiber; and curing the applied resin composition. An amount of eccentricity of a central axis of the glass fiber from a central axis based on an outer periphery of the resin composition or an outer periphery of a coated resin layer formed by curing the resin composition, in a cross-section vertical to the central axis of the glass fiber is measured at 50 points or more over a range of a length of 50 m or more of the glass fiber, and the resin composition is coated such that an average value a of the eccentricity and standard deviation σ satisfy a+3σ≤10 μm.SELECTED DRAWING: Figure 3

Embodiments of the disclosure relate to an optical fiber cable. The optical fiber cable includes an outer jacket defining a central bore extending along a longitudinal axis of the optical fiber cable. An armor layer is disposed within the first central bore and defines a second central bore extending along the longitudinal axis. A plurality of buffer tubes are disposed within the second central bore. Bedding is disposed between the plurality of buffer tubes and the armor layer. In some embodiments, a binder layer is disposed within the armor layer.

This invention belongs to the field of image transmission fiber technology and discloses a bend-insensitive high-resolution image transmission fiber and its fabrication method. The image transmission fiber provided by this invention comprises several image transmission cores and a co-cladding layer between the image transmission cores; each image transmission core includes, from the inside out, a core layer, a recessed layer, an inner cladding layer, and a light-absorbing layer; the light-absorbing layer is quartz glass containing absorber ions and fluorine. The fabrication method of the image transmission fiber provided by this invention includes preparing a light-absorbing core rod, drawing the light-absorbing core rod to obtain a light-absorbing capillary rod, stacking several light-absorbing capillary rods in a pure quartz glass sleeve to obtain an image transmission fiber preform, and drawing the image transmission fiber preform to obtain a bend-insensitive high-resolution image transmission fiber. This invention can improve the imaging resolution of the image transmission fiber, and the fabrication method has the advantages of simple and convenient process and strong production stability.

This multicore optical fiber comprises: four cores each extending along the central axis of the multicore optical fiber; a common cladding surrounding the four cores and having a lower refractive index than the refractive index of each of the four cores; and a costing resin surrounding the common cladding. The diameter of the common cladding is 124.5-125.5 μm inclusive. In each of the four cores, Aeff satisfies expression (1) and expression (2), and λcc satisfies expression (1) and expression (3).　The four cores are disposed such that Dc satisfies expression (4) with respect to Aeff and λcc of each of the first core and the second core, and OCT, Aeff, and λcc of the first core satisfy expression (5).

A laser apparatus includes an output optical fiber including a first optical waveguide and a second optical waveguide, a first laser light source that generates a laser beam, a first input optical fiber through which the laser beam generated by the first laser light source propagates, a second laser light source that generates a laser beam, a second input optical fiber through which the laser beam generated by the second laser light source propagates, and an optical combiner that is configured such that the first input optical fiber is optically connected to the first optical waveguide and the second input optical fiber is optically connected to the second optical waveguide, and directs the laser beam from the first laser light source to the first optical waveguide and the laser beam from the second laser light source to the second optical waveguide.

The multi-core optical fiber includes a plurality of cores, a first cladding, and a second cladding. The second cladding has a refractive index lower than a refractive index of each of the cores and higher than a refractive index of the first cladding. The multi-core optical fiber has a transmission loss of 0.22 dB / km or less. When an effective area of each of the cores is denoted as Aeff, a center-to-center distance between two cores is denoted as Λ, and a relative refractive index difference of each of the cores with respect to the refractive index of the first cladding is denoted as Δcore, Aeff1 is defined byAeff⁢1=18.6-4.63 ln⁢ (Δcore)+1.24Λ+2⁢4.1[ln⁢ (Δcore)]⁢2-6.05×10-3⁢Λ2-0.858Λ⁢ ln⁢ (Δcore),andthe multi-core optical fiber satisfies Condition below by using Aeff1.0.35≤Δcore≤1.25≤Λ≤5⁢00.8Aeff⁢1≤Aeff≤1.35Aeff⁢1

This optical fiber comprises a side core layer that surrounds the outer periphery of a core part, and a cladding part that surrounds the outer periphery of the side core layer, the expressions ∆1 > ∆Clad > ∆2 and 0 > ∆2 being true, where ∆1 is the average maximum relative refractive index difference of the core part with respect to the average refractive index of the cladding part, ∆2 is the relative refractive index difference of the average refractive index of the side core layer, and ∆Clad is the relative refractive index difference of the average refractive index of the cladding part with respect to pure quartz glass, the effective core cross-sectional area for a wavelength of 1550 nm is 100 µm2 to 160 µm2, (∆1 - ∆2) is 0.36% to 0.54%, ∆2 is -0.23% to -0.08%, b / a is 2.5-3.9, where 2a is the core diameter and 2b is the outside diameter of the side core layer, and the value of (∆1 - ∆2) is such that the cutoff wavelength is no more than 10 nm from the lowest value thereof.

The present disclosure provides an optical fiber (10) comprising one or more glass cores (12, 121, 122, 123, 124) extending along a length of the optical fiber (10) and a glass cladding (14) with a peripheral region (16), one or more interface regions (18, 181, 182, 183, 184) and one or more intermediate regions (20, 201, 202, 203, 204). The optical fiber (10) comprises an alumina (Al2O3) doping in the entire glass cladding (14) or at least one of the peripheral region (16), the one or more interface regions (18, 181, 182, 183, 184) and the one or more intermediate regions (20, 201, 202, 203, 204), provided that, when the optical fiber (10) comprises a single glass core (12), the alumina doping in the intermediate regions (20, 201, 202, 203, 204) is distributed among multiple intermediate regions (20, 201, 202, 203, 204) or included in combination with alumina doping in at least one of the peripheral region (16) and the one or more interface regions (18, 181, 182, 183, 184).

Provided are embodiments of an optical fiber cable. The optical fiber cable includes a cable jacket having an inner surface defining a central bore and an outer surface. A cable core including at least one optical fiber is disposed within the central bore. The cable jacket has an inner layer and an outer layer in which the inner layer extends from the inner surface to an interface between the inner layer and the outer layer and in which the outer layer extends from the outer surface to the interface. The outer layer is formed from a first polymer composition including a first polymer having a first flexural modulus, and the inner layer is formed from a second polymer composition including a second polymer having a second flexural modulus. The second flexural modulus is at least 1.5x greater than the first flexural modulus.

A hollow core fiber is provided. The hollow core fiber includes at least one cleaved fiber end-face and a dielectric coating. The dielectric coating is formed by a passivation layer of dielectric that is applied to the at least one cleaved fiber end-face such that a portion of an interior surface that defines a hollow core of the hollow core fiber adjacent to the at least one cleaved fiber end-face is coated with the dielectric coating.

This invention provides a small-diameter single-mode optical fiber with reduced coating thickness without significantly compromising puncture resistance. [Solution] The optical fiber comprises a core region, a cladding region surrounding the core region, which includes an inner cladding directly adjacent to the core region and an outer cladding surrounding the inner cladding, and a polymer coating comprising a high modulus coating layer surrounding the cladding region and a low modulus coating layer disposed between the cladding region and the high modulus coating layer. The low modulus coating layer has a layer thickness in the range of 4 μm to 20 μm and an elastic modulus of about 0.35 MPa or less, and the high modulus coating layer has a layer thickness in the range of 4 μm to 20 μm and an elastic modulus of about 1.6 GPa or more. The optical fiber has puncture resistance of more than 20 g and a microbend attenuation penalty of less than 0.03 dB / km, and the outer diameter of the coated optical fiber is 175 μm or less.

This invention discloses a graded-index non-zero dispersion-shifted optical fiber based on orbital angular momentum modes, comprising an optical fiber body including a ring core and an optical fiber cladding surrounding the ring core. The optical fiber cladding includes a circular region inside the ring core and an outer optical fiber cladding outside the ring core. This invention aims to provide a feasible optical fiber structure for suppressing four-wave mixing to meet the requirements of low-dispersion transmission of multiple orbital angular momentum modes.