With Graded Index Core Or Cladding Patents (Class 385/124)
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Patent number: 8290323Abstract: An optical multimode fiber including a graded index core and an extended gradient core which has a negative refractive index difference with respect to the cladding. The fiber improves the bandwidth, reliability and complexity of the telecommunication systems that are based on multimode fibers. The fiber reduces the differential mode delay among modes. The fiber thereby allows achieving large bandwidth even in the case when the highest order modes are excited. This has positive effects to the conditions that need to be fulfilled by the components such as optical sources, connectors, fiber couplers, other optical components, cables, etc. The fiber eliminates negative impact of the cladding that allows for reduction of fiber core size and the difference between the cladding and the core and thereby allows for achieving the larger bandwidth of optical fiber at lower fiber production cost.Type: GrantFiled: December 21, 2009Date of Patent: October 16, 2012Assignee: Corning IncorporatedInventor: Denis Donlagic
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Patent number: 8290322Abstract: Various embodiments include large cores fibers that can propagate few modes or a single mode while introducing loss to higher order modes. Some of these fibers are holey fibers that comprising cladding features such as air-holes. Additional embodiments described herein include holey rods. The rods and fibers may be used in many optical systems including optical amplification systems, lasers, short pulse generators, Q-switched lasers, etc. and may be used for example for micromachining.Type: GrantFiled: September 26, 2011Date of Patent: October 16, 2012Assignee: IMRA America, Inc.Inventors: Liang Dong, William Wong, Martin E. Fermann
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Publication number: 20120257644Abstract: The laser light emitting device includes a glass rod having an input end and an output end. The glass rod has a core provided along the central axis thereof and a cladding covering the core. The refractive index of the core on the side of the input end is higher than the refractive index of the cladding. A value given through subtraction of the refractive index of the cladding from the refractive index of the core on the side of the output end is smaller than a value given through subtraction of the refractive index of the cladding from the refractive index of the core on the side of the input end.Type: ApplicationFiled: April 23, 2012Publication date: October 11, 2012Applicant: FUJIKURA LTD.Inventor: Shinichi Sakamoto
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Patent number: 8285099Abstract: Various types of holey fiber provide optical propagation. In various embodiments, for example, a large core holey fiber comprises a cladding region formed by large holes arranged in few layers. The number of layers or rows of holes about the large core can be used to coarse tune the leakage losses of the fundamental and higher modes of a signal, thereby allowing the non-fundamental modes to be substantially eliminated by leakage over a given length of fiber. Fine tuning of leakage losses can be performed by adjusting the hole dimension and/or the hole spacing to yield a desired operation with a desired leakage loss of the fundamental mode. Resulting holely fibers have a large hole dimension and spacing, and thus a large core, when compared to traditional fibers and conventional fibers that propagate a single mode. Other loss mechanisms, such as bend loss and modal spacing can be utilized for selected modes of operation of holey fibers. Other embodiments are also provided.Type: GrantFiled: September 6, 2007Date of Patent: October 9, 2012Assignee: IMRA America, Inc.Inventors: Liang Dong, Donald J. Harter, William Wong
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Patent number: 8285101Abstract: Optical fiber apparatus having a wavelength of operation, that comprises an optical fiber including a core comprising an active material for providing light having the operating wavelength responsive to the optical apparatus receiving pump optical energy having a pump wavelength; a cladding disposed about the core; at least one region spaced from the core; and wherein the optical fiber is configured and arranged such that at the wavelength of operation the optical fiber can propagate a plurality of modes and wherein the optical fiber comprises a fundamental mode that is primarily a mode of the core and at least one higher order mode (HOM) that is a mixed mode of a selected mode of the core and of a selected mode of the at least one region.Type: GrantFiled: October 15, 2009Date of Patent: October 9, 2012Assignee: IPG Photonics CorporationInventors: Valentin P Gapontsev, Nikolai Platonov, Roman Yagodkin, Volodia Sergueev
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Publication number: 20120250143Abstract: Various embodiments described herein include rare earth doped glass compositions that may be used in optical fiber and rods having large core sizes. Such optical fibers and rods may be employed in fiber lasers and amplifiers. The index of refraction of the glass may be substantially uniform and may be close to that of silica in some embodiments. Possible advantages to such features include reduction of formation of additional waveguides within the core, which becomes increasingly a problem with larger core sizes.Type: ApplicationFiled: June 11, 2012Publication date: October 4, 2012Applicant: IMRA AMERICA, INC.Inventors: Liang Dong, Xiang Peng
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Publication number: 20120251126Abstract: An embodiment of an apparatus includes an optical fiber for which a complete orthogonal basis of propagating modes at an optical telecommunication frequency includes ones of the propagating modes with different angular momenta. The optical fiber has a tubular optical core and an outer optical cladding in contact with and surrounding the tubular optical core. The tubular optical core has a larger refractive index than the optical cladding. The tubular optical core is configured such that those of the propagating modes whose angular momenta have the lowest magnitude for the propagating modes have substantially the same radial intensity profile.Type: ApplicationFiled: March 31, 2011Publication date: October 4, 2012Inventors: Peter J. Winzer, Christopher Richard Doerr
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Publication number: 20120251062Abstract: A multimode optical fiber includes a central core surrounded by an outer cladding. The central core has a graded-index profile with respect to the outer cladding and an outer radius r1 of between about 22 microns and 28 microns. The optical fiber also includes an inner cladding positioned between the central core and the outer cladding, and a depressed trench positioned between the inner cladding and the outer cladding. The multimode optical fiber exhibits reduced bending losses.Type: ApplicationFiled: March 29, 2012Publication date: October 4, 2012Applicant: DRAKA COMTEQ, B.V.Inventors: Denis Molin, Marianne Bigot-Astruc, Pierre Sillard, Franciscus Johannes Achten
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Patent number: 8280213Abstract: The present invention embraces an optical fiber that includes a central core having an alpha refractive index profile with respect to an outer cladding. The optical fiber also includes an inner cladding, a depressed trench, and an outer cladding. The optical fiber achieves reduced bending losses and a high bandwidth with a reduced cladding effect for high-data-rate applications.Type: GrantFiled: November 24, 2010Date of Patent: October 2, 2012Assignee: Draka Comteq, B.V.Inventors: Denis Molin, Pierre Sillard
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Publication number: 20120243843Abstract: A multimode optical fiber includes a central core surrounded by an outer cladding. The central core has a graded-index profile with respect to the outer cladding and an outer radius r1 of between about 30 microns and 50 microns (e.g., between about 35 microns and 45 microns). The optical fiber also includes an inner cladding positioned between the central core and the outer cladding, and a depressed trench positioned between the inner cladding and the outer cladding. The multimode optical fiber exhibits reduced bending losses.Type: ApplicationFiled: March 23, 2012Publication date: September 27, 2012Applicant: DRAKA COMTEQ B.V.Inventors: Denis Molin, Pierre Sillard, Marianne Bigot-Astruc, Frans Gooijer, Franciscus Johannes Achten
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Publication number: 20120230638Abstract: Bend resistant multimode optical fibers are disclosed herein. Multimode optical fibers disclosed herein comprise a core region and a cladding region surrounding and directly adjacent to the core region, the cladding region comprising a first region having index delta percent ?2, a depressed-index annular portion having ?3, and a third annular region surrounding the depressed annular region comprising refractive index delta percent ?4; wherein ?1MAX>?4>?2>?3, wherein the difference between ?4 and ?2 is greater than or equal to 0.03%.Type: ApplicationFiled: February 13, 2012Publication date: September 13, 2012Inventors: Scott Robertson Bickham, Dana Craig Bookbinder, Ming-Jun Li, Gaozhu Peng, Peter Joseph Ronco, Pushkar Tandon
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Patent number: 8265440Abstract: A method for manufacturing an optical fiber preform includes the steps of depositing an inner cladding and a central core inside a fluorine doped silica tube and thereafter collapsing the silica tube to form a primary preform. The fluorine doped silica tube has a cross section area that is no more than about 15 percent smaller than the cross section area of the resulting primary preform. The present method facilitates reduced-cost manufacturing of a high-capacity optical fiber preform, which may be drawn to produce an optical fiber having reduced transmission losses.Type: GrantFiled: April 12, 2010Date of Patent: September 11, 2012Assignee: Draka Comteq, B.V.Inventors: Cedric Gonnet, Elise Regnier, Frans Gooijer, Pascale Nouchi
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Patent number: 8260103Abstract: A multimode optical fiber has an equivalent modal dispersion value (DMDinner&outer) of less than 0.11 ps/m for (??max×D)>0.07 ps/m as measured on a modified DMD graph. The modified DMD graph accounts for chromatic dispersion to ensure that the multimode optical fiber has a calculated effective bandwidth EBc greater than 6000 MHz-km when used with multimode transverse sources.Type: GrantFiled: August 8, 2011Date of Patent: September 4, 2012Assignee: Draka Comteq, B.V.Inventors: Asghar Gholami, Denis Molin, Pierre Sillard, Yves Lumineau
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Publication number: 20120219260Abstract: A method for manufacturing deuterium-treated silica glass includes exposing silica glass to a deuterium-containing atmosphere for a predetermined period of time to diffuse deuterium molecules within the silica glass, maintaining the silica glass at 40° C. or higher, and cooling the silica glass to room temperature. The silica glass is a silica glass-based optical fiber having a core made of silica glass, where the core is positioned at a center of the optical fiber and contains at least germanium, and a clad made of silica glass, where the clad surrounds the core and has a lower refractive index than the core. A surface of the silica glass is covered with a resin coating.Type: ApplicationFiled: February 24, 2012Publication date: August 30, 2012Applicant: SHIN-ETSU CHEMICAL CO., LTD.Inventor: Hiroshi OYAMADA
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Patent number: 8249407Abstract: An optical fiber that has a small bending loss can be securely prevented from being fractured due to accidental bending during installation or other operations, and is compliant with the G. 652 standard. The optical fiber includes a core, a first cladding, a second cladding and a third cladding. The relative refractive index difference ?1 of the core is in the range of 0.3% to 0.38%, the relative refractive index difference ?2 of the first cladding is equal to or smaller than 0%, and the relative refractive index difference ?3 of the second cladding is in the range of ?1.8% to ?0.5%. The inner radius r2 and the outer radius r3 of the second cladding satisfy the expression “0.4r2+10.5<r3<0.2r2+16”, and the inner radius r2 of the second cladding is equal to or greater than 8 ?m.Type: GrantFiled: November 23, 2011Date of Patent: August 21, 2012Assignee: Sumitomo Electric Industries, Ltd.Inventors: Tetsuya Nakanishi, Fumiaki Satou, Katsuyuki Aihara, Hiroshi Miyano, Takashi Sasaki
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Patent number: 8244088Abstract: A large diameter optical waveguide, grating, and laser includes a waveguide having at least one core surrounded by a cladding, the core propagating light in substantially a few transverse spatial modes; and having an outer waveguide dimension of said waveguide being greater than about 0.3 mm. At least one Bragg grating may be impressed in the waveguide. The waveguide may be axially compressed which causes the length of the waveguide to decrease without buckling. The waveguide may be used for any application where a waveguide needs to be compression tuned. Also, the waveguide exhibits lower mode coupling from the core to the cladding and allows for higher optical power to be used when writing gratings without damaging the waveguide. The waveguide may resemble a short “block” or a longer “cane” type, depending on the application and dimensions used.Type: GrantFiled: December 9, 2011Date of Patent: August 14, 2012Assignee: Weatherford/Lamb, Inc.Inventors: Martin A. Putnam, Robert N. Brucato, Paul E. Sanders, Timothy J. Bailey, James M. Sullivan, Alan D. Kersey
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Publication number: 20120195549Abstract: The present invention embraces an optical fiber that includes a central core having an alpha refractive index profile with respect to an outer optical cladding. The optical fiber also includes an inner cladding and a buried trench. The central core includes a core matrix doped with at least fluorine and a dopant element that increases refractive index. The optical fiber typically has reduced bending losses and cladding effect as well as a high bandwidth at the wavelengths of 850 nanometers and 1300 nanometers for high-data-rate applications.Type: ApplicationFiled: January 31, 2012Publication date: August 2, 2012Applicant: DRAKA COMTEQ B.V.Inventors: Denis Molin, Marianne Bigot-Astruc, Pierre Sillard, Koen de Jongh, Frans Gooijer
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Publication number: 20120195561Abstract: A multimode optical fiber includes a central core having a graded-index profile with a delta value of about 1.9 percent or greater. The graded-index core profile has at least two different alpha parameter values along the core radius, namely a first value in an inner zone of the central core and a second value in an outer zone of the central core. The second alpha parameter value is typically less than the first alpha parameter value. The graded-index core profile and its first derivative are typically substantially continuous over the width of the graded-index core.Type: ApplicationFiled: January 31, 2012Publication date: August 2, 2012Applicant: Draka Comteq B.V.Inventors: Denis Molin, Marianne Bigot-Astruc, Pierre Sillard, Koen de Jongh
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Publication number: 20120188632Abstract: Embodiments of optical fiber may include cladding features that include a material (e.g., fluorine-doped silica glass) that may produce a very low relative refractive index difference with respect to cladding material in which the cladding features are disposed. This relative refractive index difference may be characterized by (n1?n2)/n1, where n1 is the index of refraction of the cladding material in which the cladding features are included, and n2 is the index of refraction of the cladding features. In certain embodiments, the relative refractive index difference may be less than about 4.5×10?3. In various embodiments, the configuration of the cladding features including, for example, the size and spacing of the cladding features, can be selected to provide for confinement of the fundamental mode yet leakage for the second mode and higher modes, which may provide mode filtering, single mode propagation, and/or low bend loss.Type: ApplicationFiled: April 5, 2012Publication date: July 26, 2012Applicant: IMRA AMERICA, INC.Inventors: Liang Dong, Jun Li, Hugh McKay, Libin Fu, Andrius Marcinkevicius
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Publication number: 20120189258Abstract: Disclosed is an improved, single-mode optical fiber possessing 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 secondary coating provides improved ribbon characteristics for structures that are robust, yet easily entered (i.e., separated and stripped). The optional dual coating is specifically balanced for superior heat stripping in fiber ribbons, with virtually no residue left behind on the glass. This facilitates fast splicing and terminations.Type: ApplicationFiled: March 26, 2012Publication date: July 26, 2012Applicant: DRAKA COMTEQ B.V.Inventors: Bob J. Overton, Louis-Anne de Montmorillon, Simon Richard, Denis Molin, Marianne Bigot-Astruc, Pierre Sillard, David Boivin
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Patent number: 8229260Abstract: Optical fiber lasers and components for optical fiber laser. An optical fiber laser can comprise a fiber laser cavity having a wavelength of operation at which the cavity provides output light, the cavity including optical fiber that guides light having the wavelength of operation, the fiber having first and second lengths, the first length having a core having a V-number at the wavelength of operation and a numerical aperture, the second length having a core that is multimode at the wavelength of operation and that has a V-number that is greater than the V-number of the core of the first length optical fiber at the wavelength of operation and a numerical aperture that is less than the numerical aperture of the core of the first length of optical fiber. At least one of the lengths comprises an active material that can provide light having the wavelength of operation via stimulated emission responsive to the optical fiber receiving pump light.Type: GrantFiled: August 29, 2011Date of Patent: July 24, 2012Assignee: NefernInventor: Gavin P. Frith
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Publication number: 20120183267Abstract: The specification describes multimode optical fibers with specific design parameters, i.e., controlled refractive index design ratios and dimensions, which render the optical fibers largely immune to moderately severe bends. The modal structure in the optical fibers is also largely unaffected by bending, thus leaving the optical fiber bandwidth essentially unimpaired. Bend performance results were established by DMD measurements of fibers wound on mandrels vs. measurements of fibers with no severe bends. Additional embodiments of the present invention describe an improved optical link when the inventive multimode fiber is connected to standard or conventional multimode fibers.Type: ApplicationFiled: October 4, 2011Publication date: July 19, 2012Inventors: Xinli Jiang, Durgesh S. Vaidya, George E. Oulundsen
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Publication number: 20120183268Abstract: A single-mode optical fiber includes a central core, an intermediate cladding, a depressed trench, and an external optical cladding. The central core has a radius r1 and a positive refractive index difference ?n1 with the optical cladding. The intermediate cladding has a radius r2 and a refractive index difference ?n2 with the optical cladding, wherein ?n2 is less than ?n1. The depressed trench has a radius r3 and a negative index difference ?n3 with the optical cladding. At a wavelength of 1310 nanometers, the optical fiber has a mode field diameter (MFD) between 8.6 microns and 9.5 microns and, at a wavelength of 1550 nanometers, the optical fiber has bending losses less than about 0.25×10?3 dB/turn for a radius of curvature of 15 millimeters. At a wavelength of 1260 nanometers, attenuation of the LP11 mode to 19.3 dB is achieved over less than 90 meters of fiber.Type: ApplicationFiled: March 26, 2012Publication date: July 19, 2012Applicant: DRAKA COMTEQ B.V.Inventors: Louis-Anne de Montmorillon, Simon Richard, Denis Molin, David Boivin, Marianne Bigot-Astruc, Pierre Sillard
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Publication number: 20120177329Abstract: A coated plastic cladding optical fiber and an optical fiber cable, in which a transmission loss caused when this coated fiber or this fiber cable is bent in a small radius is small, and which can be used sufficiently as a USB cable or a HDMI cable in a high speed transmission, are provided. The coated plastic cladding optical fiber 1 has a cladding layer 3 that is formed on an outer periphery of a core glass 2 made of a quartz glass and formed of a polymer resin whose refractive index is lower than core glass, and a resin coating layer 5 that is formed on an outer periphery of the cladding layer 3 and is formed of a thermosetting resin. Then, a diameter of the core glass 2 is set to 50 to 100 ?m, and a relative index difference of the core glass 2 to the cladding layer 3 is set to 3.7% or more.Type: ApplicationFiled: April 18, 2011Publication date: July 12, 2012Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Itaru Sakabe, Kazuyuki Sohma, Tomoyuki Hattori, Takashi Takada, Toshiaki Kakii
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Publication number: 20120177333Abstract: An optical fiber includes a center core portion; an inner core layer formed around an outer circumference of the center core portion, a refractive index of which is less than that of the center core portion; an outer core layer formed around an outer circumference of the inner core layer, a refractive index of which is less than that of the inner core layer; and a cladding portion formed around an outer circumference of the outer core layer. A refractive index of the cladding portion is substantially equal to that of the inner core layer. At a wavelength of 1550 nm, an effective core area is equal to or larger than 130 ?m2 and a bending loss is equal to or less than 100 dB/m when the optical fiber is bent with a diameter of 20 mm. A cable cut-off wavelength is equal to or less than 1530 nm.Type: ApplicationFiled: March 16, 2012Publication date: July 12, 2012Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Yukihiro TSUCHIDA, Kazunori MUKASA
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Patent number: 8218928Abstract: 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.Type: GrantFiled: April 23, 2009Date of Patent: July 10, 2012Assignee: OFS Fitel, LLCInventor: Jayesh C. Jasapara
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Patent number: 8208775Abstract: A silica-based multi core optical fiber and a fabrication method for the same are provided, and include two or more cores of GeO2—SiO2 glass including an fluorine concentration not less than about 15 w % and a germanium concentration about 0.05 wt % to 2 wt %, in a core. A relative refractive index difference of a cladding and a core is not less than about 3%; and a ratio of a cladding diameter to a core diameter is about 1.02 to 3.0. A silica-based single core optical fiber is also provided, and includes a core having a germanium concentration not less than about 15 wt % and an fluorine concentration about 0.05 wt % to 2 wt %.Type: GrantFiled: October 21, 2010Date of Patent: June 26, 2012Assignee: Fujikura Ltd.Inventors: Manabu Kudou, Kazuyuki Hayashi, Takashi Tsumanuma
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Publication number: 20120148207Abstract: In one embodiment, an waveguide includes a primary core configured to guide electromagnetic waves having relatively long wavelengths, a unit cell having a core configured to guide electromagnetic waves having relatively short wavelengths, the relatively long wavelengths being at least twice as long as the relatively short wavelengths, and a cladding material that surrounds the primary core and the unit cell.Type: ApplicationFiled: December 9, 2011Publication date: June 14, 2012Applicant: University of Central Florida Research Foundation, Inc.Inventors: Guifang Li, Fatih Yaman
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Patent number: 8200057Abstract: A single mode fiber having a core, an inner cladding, a depressed cladding, and an outer cladding composed of pure silica glass. The core is surrounded in sequence with the inner cladding and the depressed cladding. The core has silica glass doped with germanium and fluorine, with a diameter (a) of 8.0-8.8 ?m, a relative refractive index difference (?1) of 0.35-0.38%, and the contribution of fluoride (?F) is ?0.09±0.02%. The inner cladding has silica glass doped with germanium and fluorine, with a diameter (b) of 18-21 ?m and a relative refractive index difference (?2) of 0±0.02%. The depressed cladding has silica glass doped with fluorine, with a diameter (c) of 26-36 ?m and a relative refractive index difference (?32) at the external interface thereof is between ?0.22 and ?0.35%, and a relative refractive index difference (?31) at the internal interface thereof is between ?0.20 and ?0.35%, and ?32??31.Type: GrantFiled: July 20, 2010Date of Patent: June 12, 2012Assignee: Yangtze Optical Fibre and Cable Company, Ltd.Inventors: Qingrong Han, Chen Yang, Jing Li, Jie Luo
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Publication number: 20120140609Abstract: An apparatus includes a waveguide having a core layer and first and second cladding layers on opposite sides of the core layer, wherein the cladding layers comprise a binary oxide composition. In another example, the cladding layers include a ternary or quaternary combination of oxides and/or oxynitrides. In another example, the cladding layers include a silicon oxynitride.Type: ApplicationFiled: February 10, 2012Publication date: June 7, 2012Applicant: SEAGATE TECHNOLOGY LLCInventors: Xiaoyue Huang, Michael Christopher Kautzky, Amit Itagi, William Albert Challener, Michael Allen Seigler
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Publication number: 20120141078Abstract: An optical fiber includes a core portion that confines light therein and guides the light therethrough and a cladding portion that is formed around an outer circumference of the core portion. The cladding portion contains a hole which is formed at a position a distance away from the core portion such that the hole does not substantially affect an effective core area or a chromatic dispersion characteristic of the optical fiber. The hole decreases a microbending loss of the optical fiber.Type: ApplicationFiled: February 13, 2012Publication date: June 7, 2012Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Kazunori MUKASA, Yukihiro TSUCHIDA
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Patent number: 8189978Abstract: Bend resistant multimode optical fibers are disclosed herein. Multimode optical fibers disclosed herein comprise a core region having a radius greater than 30 microns and a cladding region surrounding and directly adjacent to the core region, the cladding region comprising a depressed-index annular portion comprising a depressed relative refractive index. The fiber has a total outer diameter of less than 120 microns, and exhibits an overfilled bandwidth at 850 nm greater than 500 MHz-km.Type: GrantFiled: September 24, 2009Date of Patent: May 29, 2012Assignee: Corning IncorporatedInventors: Randy Lee Bennett, Scott Robertson Bickham, Paulo Clóvis Dainese, Jr., Ming-Jun Li, Peter Joseph Ronco
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Patent number: 8184936Abstract: A multimode fiber including a core and a cladding. The core has a radius (R1) of 24-26 ?m, the refractive index profile thereof is a parabola, and the maximum relative refractive index difference (?1) is 0.9-1.1%. The cladding surrounds the core and includes from inside to outside an inner cladding, a middle cladding, and an outer cladding; a radius (R2) of the inner cladding is 1.04-1.6 times that of the core, and a relative refractive index difference (?2) thereof is ?0.01-0.01%; the middle cladding is a graded refractive index cladding whose radius (R3) is 1.06-1.8 times that of the core, and a relative refractive index difference thereof is decreased from ?2 to ?4; and a radius (R4) of the outer cladding is 2.38-2.63 times that of the core, and a relative refractive index difference (?4) thereof is between ?0.20 and ?0.40%.Type: GrantFiled: July 19, 2010Date of Patent: May 22, 2012Assignee: Yangtze Optical Fibre and Cable Company, Ltd.Inventors: Fanghai Zhang, Beibei Cao, Qingrong Han, Raadjkoemar Matai
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Publication number: 20120114292Abstract: Multi-core optical fiber ribbons and methods for making multi-core optical fiber ribbons are described herein. In one embodiment, a multi-core optical fiber ribbon includes at least two core members formed from silica-based glass and oriented in parallel with one another in a single plane. Adjacent core members have a center-to-center spacing ?15 microns and a cross-talk between adjacent core members is ??25 dB. In this embodiment each core member is single-moded with an index of refraction nc, and a core diameter dc. In an alternative embodiment, each core member is multi-moded and the center-to-center spacing between adjacent core members is ?25 microns. A single cladding layer is formed from silica-based glass and surrounds and is in direct contact with the core members. The single cladding layer is substantially rectangular in cross section with a thickness ?400 microns and an index of refraction nc1?nc.Type: ApplicationFiled: October 14, 2011Publication date: May 10, 2012Inventors: Brett Jason Hoover, Ming-Jun Li
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Publication number: 20120106909Abstract: An optical fiber includes a central glass core region comprising maximum refractive index delta percent ?1, a first inner annular region surrounding said core comprising refractive index delta percent ?2, a depressed annular region surrounding said inner annular region and comprising ?3 and a third annular region surrounding the depressed annular region comprising refractive index delta percent ?4; wherein ?1MAX>?4>?2>?3. The difference between ?4 and ?2 is greater than 0.01% and profile volume, |V3| is at least 10%-?m2. The fibers exhibit an effective area at 1550 nm which is greater than 110 ?m2.Type: ApplicationFiled: October 29, 2010Publication date: May 3, 2012Inventors: Scott Robertson Bickham, Dana Craig Bookbinder, Ming-Jun Li, Snigdharaj Kumar Mishra, Pushkar Tandon
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Publication number: 20120092651Abstract: A method of selecting a multimode optical fiber includes determining a first modal bandwidth value BW for each of a plurality of multimode optical fibers in a straight position and determining a second modal bandwidth value bBW for each of a plurality of multimode optical fibers in a bent position. Typically, the method includes selecting the multimode optical fibers for which the second modal bandwidth value bBW is greater than a threshold bandwidth A. The threshold bandwidth A may be (i) a function of the multimode optical fiber's first modal bandwidth value BW and a bending-loss value BL and (ii) greater than the multimode optical fiber's first modal bandwidth value BW.Type: ApplicationFiled: October 18, 2011Publication date: April 19, 2012Applicant: DRAKA COMTEQ FRANCEInventors: Denis Molin, Pierre Sillard
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Publication number: 20120087626Abstract: A multi-core optical fibre 1A in which a plurality of cores can easily be identified even in the case where they are symmetrically arranged in its section has seven cores 10 to 16, a visual recognition marker 20, and a shared cladding 30 enclosing the seven cores 10 to 16 and the visual recognition marker 20. The cores 10 to 16 and the visual recognition marker 20 extend along the fibre-axis direction. The respective refractive index of the cores 10 to 16 is higher than the refractive index of the cladding 30. The refractive index of the visual recognition marker 20 differs from that of the cladding 30. In the cross-section perpendicular to the fibre-axis, the cores 10 to 16 are arranged such that they have 6-fold rotational symmetry and line symmetry. The visual recognition marker 20 is arranged at a position which breaks such symmetry.Type: ApplicationFiled: January 26, 2011Publication date: April 12, 2012Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Takuji Nagashima, Toshiki Taru, Takashi Sasaki
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Publication number: 20120087625Abstract: A fiber preform, including: a fiber core rod and an outer cladding layer. The ratio of the diameter of the fiber core rod to the diameter of the core layer thereof is 2.1-2.8. The fiber core rod and a small fluorine-doped quartz glass tube are melted to form a core rod assembly. The ratio of the diameter difference between the core rod assembly and the fiber core rod to the diameter of the core layer is 0.5-2.2. The relative refractive index difference of fluorine-doped quartz glass relative to purified quartz glass ?F is ?0.20% to ?0.35%. The core rod assembly is arranged with a large purified quartz glass tube, or directly deposited with a SiO2 glass cladding layer. A ratio of an effective diameter of the fiber preform to the diameter of the core rod assembly is 2.0-5.6. Methods for manufacturing the preform and a fiber are also provided.Type: ApplicationFiled: December 15, 2011Publication date: April 12, 2012Inventors: Qingrong HAN, Chen YANG, Yongtao LIU, Jie LUO, Matai RADJJ
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Publication number: 20120076465Abstract: An apparatus that comprises an optical-mode-converter. The optical-mode-converter includes a optical waveguide including a segment directly located on a substrate and a cantilevered segment located over said substrate and separated from said substrate by a cavity, and, said cantilevered segment includes a core surrounded by a cladding. The optical-mode-converter also includes a dielectric material filling said cavity and contacting said cantilevered segment over said cavity, wherein said dielectric material has a refractive index that is less than a refractive index of said cladding and that is no more than about 20 percent less than said refractive index of said cladding.Type: ApplicationFiled: September 27, 2010Publication date: March 29, 2012Applicant: Alcatel-Lucent, USA Inc.Inventors: Long Chen, Christopher R. Doerr, Young Kai Chen
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Patent number: 8145024Abstract: The present invention relates to an optical communications system that allows improving OSNR while suppressing the power increase of pumping light for distributed Raman amplification. In the optical communications system, an optical fiber is laid in a transmission section between a transmitter station (or repeater station) and a receiver station (or repeater station), and optical signals are transmitted from the transmitter station to the receiver station via the optical fiber. In the optical communications system, pumping light for Raman amplification, outputted by a pumping light source provided in the receiver station, is fed into the optical fiber via an optical coupler, and the optical signals are distributed-Raman-amplified in the optical fiber. The transmission loss and the effective area of the optical fiber satisfy, at the wavelength of 1550 nm, a predetermined relationship.Type: GrantFiled: August 5, 2010Date of Patent: March 27, 2012Assignee: Sumitomo Electric Industries, Ltd.Inventors: Eisuke Sasaoka, Kazuya Kuwahara
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Patent number: 8145025Abstract: A single-mode optical fiber includes a central core, an intermediate cladding, a depressed trench, and an external optical cladding. The central core has a radius r1 and a positive refractive index difference ?n1 with the optical cladding. The intermediate cladding has a radius r2 and a positive refractive index difference ?n2 with the optical cladding, wherein ?n2 is less than ?n1. The depressed trench has a radius r3 and a negative index difference ?n3 with the optical cladding. At a wavelength of 1310 nanometers, the optical fiber has a mode field diameter (MFD) between 8.6 microns and 9.5 microns and, at a wavelength of 1550 nanometers, the optical fiber has bending losses less than about 0.25×10?3 dB/turn for a radius of curvature of 15 millimeters. At a wavelength of 1260 nanometers, attenuation of the LP11 mode to 19.3 dB is achieved over less than 90 meters of fiber.Type: GrantFiled: May 6, 2009Date of Patent: March 27, 2012Assignee: Draka Comteq, B.V.Inventors: Louis-Anne de Montmorillon, Simon Richard, Denis Molin, David Boivin, Marianne Bigot-Astruc, Pierre Sillard
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Publication number: 20120069428Abstract: The invention relates to an optical fiber as an optical waveguide for the single-mode operation. The present invention proposes a fiber having a microstructure, by which the propagation of modes of a higher order are selectively suppressed in the optical waveguide. At the same time, the propagation of transversal modes of a higher order is dampened more strongly than the propagation of the fundamental modes of the optical waveguide.Type: ApplicationFiled: March 12, 2010Publication date: March 22, 2012Applicants: FRIEDRICH-SCHILLER-UNIVERSITÄT JENA, FRAUNHOFER-GESELLSCHAFT ZUR FÖRDERUNG DER ANGEWANDTEN FORSCHUNG E.V.Inventors: Jens Limpert, Fabian Roeser, Tino Eidam, César Jáuregui Misas, Andreas Tuennermann
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Publication number: 20120069858Abstract: Photodarkening resistant optical fiber lasing media and fiber lasers incorporating the same are disclosed. In one embodiment, an optical fiber lasing medium includes a core portion formed from silica-based glass comprising a rare-earth dopant and deuterium, the core portion having an index of refraction nc, a numerical aperture NAc. A concentration of defect color centers in the core portion is less than 1×1016/cm3. Deuterium is combined with the defect color centers to form reacted defect color centers that do not absorb ultraviolet and visible wavelengths of light. A first cladding portion is formed from silica-based glass, the first cladding portion surrounding and directly contacting the core portion and having an index of refraction n1, wherein the index of refraction n1 of the first cladding portion is less than the index of refraction ncof the core portion. Methods of forming the photodarkening resistant optical fiber lasing media are also disclosed.Type: ApplicationFiled: October 20, 2010Publication date: March 22, 2012Inventors: Stuart Gray, Shenping Li, Ji Wang
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Patent number: 8139912Abstract: An optical fiber apparatus having a wavelength of operation comprises an optical fiber comprising a core; a pump cladding disposed about the core for receiving pump optical energy having a pump wavelength; and a second cladding disposed about for tending to confine pump optical energy to the pump cladding. The core can comprise a rare earth material for providing optical energy having the wavelength of operation responsive to the optical fiber receiving the pump optical energy, and the fiber can further comprise at least one ring core spaced from the core, the ring core defined by inner and outer diameters and comprising the cross sectional area therebetween. The ring core can comprise an absorbing material for absorbing optical energy having the wavelength of operation.Type: GrantFiled: October 16, 2009Date of Patent: March 20, 2012Assignee: IPG Photonics CorporationInventors: Valentin P Gapontsev, Nikolai Platonov, Roman Yagodkin, Volodia Sergueev
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Publication number: 20120063734Abstract: A multimode graded-index plastic optical fiber comprises a cladding and a core. The core has a refractive index which continuously becomes higher as closer to a center of a circular cross-section of the core. The core propagates light of a first mode group, which should be propagated, of incoming light from one end face of the core and emits the light from the other end face of the core. The cladding is provided on a periphery of the core and has a cylindrical cross-section. The cladding has a refractive index which is lower than that of the core. The cladding deflects light of the first mode group at an interface with the core. The core has a first core section, a second core section and a third core section. The first core section contacts an inner circumference of the cladding. The second core section is inside the first core section, and is inside the core. The second core section is a light scattering section which scatters light of a second mode group of the incoming light outside.Type: ApplicationFiled: September 9, 2010Publication date: March 15, 2012Inventor: Yasuhiro KOIKE
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Publication number: 20120051703Abstract: A single-mode optical fiber includes a central core, an intermediate cladding, a buried trench, and optical cladding. The central core has an outer radius r1 and a refractive index difference ?n1 relative to the optical cladding. The intermediate cladding has an outer radius r2 and a refractive index difference ?n2 relative to the optical cladding. The buried trench has an outer radius r3 and a refractive index difference ?n3 relative to the optical cladding. The optical fiber typically has an effective area of about 150 ?m2 or greater at a wavelength of 1550 nanometers and exhibits low bending losses.Type: ApplicationFiled: July 1, 2011Publication date: March 1, 2012Applicant: DRAKA COMTEQ B.V.Inventors: Marianne Bigot-Astruc, Pierre Sillard, Simon Richard
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Publication number: 20120039361Abstract: A multi-mode optical waveguide fiber including a central core region having an outer radius surrounded by an inner cladding region having an outer radius, the inner cladding region having a lower index of refraction than the central core region, wherein both the central core and inner cladding regions are doped with fluorine, wherein the refractive index profile of the central core region is of the gradient index type and the central core region in the range of r?[0-ra] comprises germanium at a maximum concentration within the range of 0.5 percent by weight to 4.0 percent by weight taken at a given radius, wherein said fiber has an Overfilled Modal Bandwidth >500 MHz·km at a wavelength of 850 nm and 1300 nm, according to IEC 60793-2-10.Type: ApplicationFiled: August 12, 2011Publication date: February 16, 2012Applicant: DRAKA COMTEQ B.V.Inventors: Frans GOOIJER, Gertjan KRABSHUIS, Elise REGNIER, Adrian AMEZCUA-CORREA, Pieter MATTHIJSSE, Denis MOLIN
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Patent number: 8111962Abstract: An optical fiber connection structure which reduces MPI in the use of an optical fiber with a bend resistance improved by forming holes in the fiber, and a single-mode fiber which reduces MPI are provided. A second cladding portion of a second single-mode fiber 20 includes holes 28, and thus, the second single-mode fiber 20 has low bending loss. A portion of the second single-mode fiber 20 connected to a first single-mode fiber 10a is made solid by filling corresponding portions of the holes 28 over the length L0, and light in a mode LP11 is significantly attenuated in this portion, thereby reducing MPI.Type: GrantFiled: August 21, 2009Date of Patent: February 7, 2012Assignee: Mitsubishi Cable Industries, Ltd.Inventors: Masatoshi Tanaka, Masayoshi Hachiwaka, Haruo Ooizumi
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Patent number: 8107782Abstract: The present invention is directed to the creation of optical waveguiding devices from standard optical fibers by the creation of zones of permanently altered refractive index characteristics therein. A high intensity femtosecond laser beam is focused at a predetermined target region in the fiber so as to soften the glass material at the target region. After aligning the focal region with the target region in the fiber there will be relative movement between the focal region and the fiber, which has the effect of sweeping the focal region across the fiber in a predetermined path, so as to create a secondary waveguide path. A portion of the light traveling along the core is removed from the core along the secondary waveguide path such that the device can be utilized as an attenuator, an optical tap, or a polarimeter.Type: GrantFiled: November 13, 2007Date of Patent: January 31, 2012Assignees: OZ Optics Ltd, Femtonics CorporationInventors: Omur M. Sezerman, Kenneth O. Hill, Garland Best, Dwayne R. J. Miller, Michael Armstrong, Shujie Lin
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Publication number: 20120014654Abstract: Provided is an optical fiber having a large relative refractive index difference and a reduced transmission loss, as well as a manufacturing method therefor. An optical fiber preform 100, which is made of silica glass as the main element and which includes a core region having a relative refractive index difference of 2.0% or more and less than 3.0% on the basis of the refractive index of pure silica glass and a first cladding region provided around the core region and having a relative refractive index difference of ?0.8% or more and less than ?0.3% on the basis of the refractive index of pure silica glass, is drawn into a glass fiber. The glass fiber thus drawn is passed through an annealing furnace 21 installed below a drawing furnace 11, whereby the cooling rate of the glass fiber is restrained as compared with the case where it is cooled by air.Type: ApplicationFiled: July 13, 2011Publication date: January 19, 2012Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Tetsuya HARUNA, Masaaki Hirano, Nobuhiro Hikichi