Abstract: A multi-core optical fiber according to the present invention includes plural single-core optical fibers, and comprises an intermediate portion in which a side surface of each single-core optical fiber is covered with a resin layer, and a terminal portion in which the each single-core optical fiber is exposed from the resin layer. In the terminal portion of the multi-core optical fiber, the single-core optical fibers are separated from each other.

Abstract: 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.

Abstract: The present invention relates to an optical cable with a structure for improving a durability performance. The optical cable comprises, as a basic structure: a coated optical fiber, and a cable jacket covering an outer periphery of the coated optical fiber. The coated optical fiber is constituted by a glass fiber and a coating layer of an ultraviolet curing resin. To realize excellent impact resistance as durability performance, the coating layer of the coated optical fiber includes a first coating with a Young's modulus of 200 MPa or more. Meanwhile, the cable jacket is comprised of a thermoplastic resin that does not contain any halogens. The cable jacket has a thickness of 0.7 mm or more, a flame retardancy of V2 or more according to UL Standards, and a Young's modulus equal to or greater than that of the first coating.

Abstract: The stranded optical cable 10 includes a plurality of stranded multicore optical cables 12 and a cable sheath 16 covering the multicore optical cables 12, each multicore optical cable 12 including at least two of optical units 13 as a pair and a unit sheath 14 covering the optical units 13, each optical unit 13 being formed by bundling a plurality of optical fibers. And, parts of the cable sheath corresponding to both ends of the stranded optical cable 10 are removed to expose the multicore optical cables 12 certain lengths so that the optical connectors 21 are connected to the multicore optical cables 12, respectively.

Abstract: The present invention relates to an optical cable with a structure for improving a durability performance. The optical cable comprises, as a basic structure: a coated optical fiber, and a cable jacket covering an outer periphery of the coated optical fiber. The coated optical fiber is constituted by a glass fiber and a coating layer of an ultraviolet curing resin. To realize excellent impact resistance as durability performance, the coating layer of the coated optical fiber includes a first coating with a Young's modulus of 200 MPa or more. Meanwhile, the cable jacket is comprised of a thermoplastic resin that does not contain any halogens. The cable jacket has a thickness of 0.7 mm or more, a flame retardancy of V2 or more according to UL Standards, and a Young's modulus equal to or greater than that of the first coating.

Abstract: When a glass fiber and an inner fiber coating layer are to be attached to a connector by removing an outer fiber coating layer while leaving the inner fiber coating layer as it is, a collective coating and the outer fiber coating layer can be removed at a stretch so that the inner fiber coating layer can easily and satisfactorily be exposed. In the ultraviolet curable resin coating layer of a coated optical fiber 17 of an optical fiber ribbon 11 for wiring of equipment, the inner fiber coating layer 15 has a Young's modulus of 600 MPa to 1000 MPa, and the outer fiber coating layer 16 has a Young's modulus of 10 MPa to 300 MPa. The material of the outer fiber coating layer 16 is made by mixing 100 weight parts of base resin, 1-30 weight parts of silicone-based additive, and 0.5 to 40 weight parts of long chain fatty acid ester compound, wherein the base resin is a material made of a urethane metha acrylate oligomer, a mono-functional or multi-functional reactive dilution monomer, and an optical initiator.

Abstract: When a glass fiber and an inner fiber coating layer are to be attached to a connector by removing an outer fiber coating layer while leaving the inner fiber coating layer as it is, a collective coating and the outer fiber coating layer can be removed at a stretch so that the inner fiber coating layer can easily and satisfactorily be exposed. In the ultraviolet curable resin coating layer of a coated optical fiber 17 of an optical fiber ribbon 11 for wiring of equipment, the inner fiber coating layer 15 has a Young's modulus of 600 MPa to 1000 MPa, and the outer fiber coating layer 16 has a Young's modulus of 10 MPa to 300 MPa. The material of the outer fiber coating layer 16 is made by mixing 100 weight parts of base resin, 1-30 weight parts of silicone-based additive, and 0.5 to 40 weight parts of long chain fatty acid ester compound, wherein the base resin is a material made of a urethane metha acrylate oligomer, a mono-functional or multi-functional reactive dilution monomer, and an optical initiator.

Abstract: An object of the present invention is to provide a buffered optical fiber, which excels in environmental characteristics and mechanical characteristics and has high flame retardancy and excels in optical transmission characteristics, and to provide a buffered optical fiber, which is terminated with a connector and uses this buffered optical fiber. The buffered optical fiber of the invention is provided with a second coating layer on an outer peripheral surface of an optical fiber produced by providing a first coating layer on an outer peripheral surface of a glass fiber. A second resin composition constituting the second coating layer comprises 100 to 250 weight parts of metal hydroxide and 10 to 100 weight parts of a nitrogen-based flame retardant material per 100 weight parts of the base polymer. Further, the second resin composition does not contain halogenated materials.

Abstract: A plurality of optical fibers are arranged in parallel and peripheries of the plurality of these optical fibers are integrally formed using a sheath. Here, the sheath is formed over the entire length of optical fiber ribbons and a flat portion of the sheath is formed substantially parallel to a common tangent of the neighboring optical fibers. A maximum value of a thickness of the optical fiber ribbons is set to a value which is larger than an outer diameter of the optical fibers by 40 ?m or less. Due to such a constitution, it is possible to easily branch the optical fibers from the integrally formed optical fiber ribbons.

Abstract: In an optical fiber ribbon 1 according to the present invention, four optical fibers 10, 20, 30 and 40 are arranged in parallel to each other in a plane, a part of the periphery of these four optical fibers is covered with a ribbon matrix 51, but no rest thereof is covered with the ribbon matrix. First areas covered with the ribbon matrix 51 and second areas uncovered with the ribbon matrix alternate with each other along the longitudinal direction thereof. Alternatively, the optical fiber ribbon 1 is covered with the ribbon matrix over its entire length. In the glass section of each optical fibers, the mode field diameter defined by the definition of Petermann-I at a wavelength of 1.55 ?m is 8 ?m or less, and the cable cutoff wavelength is 1.26 ?m or less.

Abstract: The present invention relates to an optical fiber and the like comprising a structure enabling high-density packaging into an optical cable while making it possible to transmit signals with a high bit rate in both of wavelength bands of 1.3 ?m and 1.55 ?m. For example, this optical fiber is configured so as to have a mode field diameter of 8.0 ?m or less at a wavelength of 1.55 ?m, a cutoff wavelength of 1.26 ?m or less, and a chromatic dispersion with an absolute value of 12 ps/nm/km or less at wavelengths of 1.3 ?m and 1.55 ?m, thereby yielding an excellent lateral pressure resistance enabling high-density packaging into an optical cable.

Abstract: An object of the present invention is to provide a buffered optical fiber, which excels in environmental characteristics and mechanical characteristics and has high flame retardancy and excels in optical transmission characteristics, and to provide a buffered optical fiber, which is terminated with a connector and uses this buffered optical fiber. The buffered optical fiber of the invention is provided with a second coating layer on an outer peripheral surface of an optical fiber produced by providing a first coating layer on an outer peripheral surface of a glass fiber. A second resin composition constituting the second coating layer comprises 100 to 250 weight parts of metal hydroxide and 10 to 100 weight parts of a nitrogen-based flame retardant material per 100 weight parts of the base polymer. Further, the second resin composition does not contain halogenated materials.

Abstract: In an optical fiber ribbon 1 according to the present invention, four optical fibers 10, 20, 30 and 40 are arranged in parallel to each other in a plane, a part of the periphery of these four optical fibers is covered with a ribbon matrix 51, but no rest thereof is covered with the ribbon matrix. First areas covered with the ribbon matrix 51 and second areas uncovered with the ribbon matrix alternate with each other along the longitudinal direction thereof. Alternatively, the optical fiber ribbon 1 is covered with the ribbon matrix over its entire length. In the glass section of each optical fibers, the mode field diameter defined by the definition of Petermann-I at a wavelength of 1.55 ?m is 8 ?m or less, and the cable cutoff wavelength is 1.26 ?m or less.

Abstract: The present invention provides a coated optical fiber in which a silica type optical fiber is coated with n layers (n being an integer of 2 or greater) of UV-curable resin, wherein the sum of respective contraction stress indices FI defined in the n layers of UV-curable resin by the following expression: FI [N]=(Young's modulus [MPa] of the UV-curable resin layer at ?40° C.)×(cross-sectional area [mm2] of the UV-curable resin layer)×(effective linear expansion coefficient [10?6/° C.]/106)×(temperature difference 190[° C.]) is 3 [N] or less. The present invention can sufficiently prevent transmission characteristics from deteriorating in a low temperature environment.

Abstract: The separable optical fiber ribbon in accordance with the present invention is an optical fiber ribbon in which a plurality of colored optical fibers arranged in parallel are coated with a collective coating resin so as to be integrated into an optical fiber ribbon, and a plurality of such optical fiber ribbons are arranged in parallel and coated with a binding resin; wherein the binding resin is obtained by curing a UV-curable resin composition satisfying the condition represented by the following expression (1): 1.0×10?4?(W·N/100MW)?4.0×10?4??(1) where W is the compounding ratio [wt %] of a urethane acrylate compound contained in the resin composition, N is the number of urethane groups in one molecule of the urethane acrylate compound, and MW is the average molecular weight of the urethane acrylate compound.

Abstract: A coated optical fiber is shown in which, by coating a glass optical fiber with a primary coating having a storage modulus E′ of 0.01 kg/mm2 to 2.0 kg/mm2 at 25° and 110 Hz and an adhesion of 10 g/cm to 200 g/cm to the glass optical fiber, delamination at the interface between the glass optical fiber and the primary coating, and voids are prevented during and after the production, for example, on the line during drawing and winding. An optical fiber ribbon of the present invention, which is formed by collectively coating the coated optical fibers each including a primary coating with a storage modulus E′ of 0.01 kg/mm2 to 0.5 kg/mm2 and an adhesion of 10 g/cm to 100 g/m, has a high delamination resistance and a good collective strippability of coatings. In an optical fiber unit of the present invention which is formed by collectively coating the coated optical fibers having a storage modulus E′ of 0.01 kg/mm2 to 0.

Abstract: The permanent magnet type reluctance electric motor includes a stator including a stator iron core and having armature coils placed inside slots, and a rotor provided with a plurality of magnetic barriers formed by cavities and placed on an inner side of the stator such that sections where a magnetic flux can easily pass (d-axis) and sections where a magnetic flux cannot easily pass (q-axis) are alternately formed, and made of a rotor iron core having permanent magnets in cavities. The rotor satisfies a relationship of PL/2&pgr;RWqave≧130, where Wqave [m] indicates an average thickness of the rotor iron core on an outer side in a radial direction of the rotor with respect to cavities arranged in a q-axis direction, L [m]; a width in a circumferential direction of the cavities, P; the number of poles and R [m]; the radius of the rotor.

Abstract: A plurality of optical fibers are arranged in parallel and peripheries of the plurality of these optical fibers are integrally formed using a sheath. Here, the sheath is formed over the entire length of optical fiber ribbons and a flat portion of the sheath is formed substantially parallel to a common tangent of the neighboring optical fibers. A maximum value of a thickness of the optical fiber ribbons is set to a value which is larger than an outer diameter of the optical fibers by 40 &mgr;m or less. Due to such a constitution, it is possible to easily branch the optical fibers from the integrally formed optical fiber ribbons.

Abstract: The heat-resistant coated optical fiber in accordance with the present invention comprises a coating portion 20, coated on the outer periphery of an optical fiber 10, comprising a first coating layer 21 consisting of aromatic polyimide resin, a second coating layer 22 consisting of silicone resin, and a third coating layer 23 consisting of moisture-resistant resin with a heat resistance equivalent to that of the first coating layer 21, e.g., PFA.

Abstract: The separable optical fiber ribbon in accordance with the present invention is an optical fiber ribbon in which a plurality of colored optical fibers arranged in parallel are coated with a collective coating resin so as to be integrated into an optical fiber ribbon, and a plurality of such optical fiber ribbons are arranged in parallel and coated with a binding resin; wherein the binding resin is obtained by curing a UV-curable resin composition satisfying the condition represented by the following expression (1):