Nippon Telegraph and Telephone Corporation

Sumitomo Electric Industries, Limited

Hitachi Cable, Inc.

Hitachi Metals, Ltd.

The Furukawa Electric Co., Ltd.

Other

Okano Electric Wire Co., Ltd.

Masao Tachikura

Masayuki Nishimura

Kazuhito Saito

Hideo Kobayashi

Kazumasa Ohsono

Toshiaki Katagiri

Shigenori Uruno

Tohru Yamanishi

Toshio Kurashima

Yoshinori Kurosawa

Eiji Araki

Hajime Takemoto

Katumi Hiramatu

Bing Yao

Hisashi Izumita

Hisanori Nakai

Yoshikazu Namekawa

Yoshiyuki Hiramoto

Noribumi Shiina

Nobuhisa Ishii

Isao Nakanishi

Fuminori Nakajima

Hitoshi Ishimaru

Kuniaki Yamaguchi

Kanako Suzuki

Kenji Kawase

Nobuo Tomita

Masaru Ishikawa

Tsuyoshi Shimomichi

Tatsuo Teraoka

Yoshitaka Enomoto

Keiji Oohashi

Naoki Nakao

Toshihiko Ishikawa

Etsuo Ino

Koji Mine

Akira Hirooka

Mitsumasa Zobuchi

Tetsuo Hayano

Fumi Miyata

Katuyoshi Ishida

Hiroyuki Ohkubo

Kazunaga Kobayashi

Kyoji Osozawa

Motoyoshi Nakamura

An optical fiber end processing method includes the steps of: an optical fiber fixing step of fixing two parts of the optical fiber; a first heating step of heating a tip end side part of the optical fiber between two fixed parts fixed in the optical fiber fixing step, and melting the optical fiber of the tip end side heating part; a second heating step of heating a part on a base end side of the optical fiber between the fixed parts away from the tip end side heating part in a state that two parts of the optical fiber are fixed, and making the holes of the optical fiber disappear; and a removing step of removing the tip end side heating part after the second heating step.

Optical fiber end processing method and optical fiber end processing apparatus

An optical fiber which, at an optical fiber connecting end having a plurality of voids around the periphery of a core, has a light-permeable substance, such as a resin or glass whose refractive index is lower than that of quartz type substances, filled in the voids adjacent to the connecting end. An optical fiber connecting section where an optical fiber having a plurality of voids in a clad around the periphery of a core is connected to another optical fiber, wherein the optical fiber is connected end-to-end to aforesaid another optical fiber through a refractive index matching agent whose refractive index at the minimum temperature in actual use is lower than that of the core.

Method of sealing air holes in an optical fiber

An optical fiber end processing method includes fixing two portions of an optical fiber, heating and fusing the optical fiber between the two fixed portions, to form a first heat fusion region, heating and fusing the optical fiber fixed between the two fixed portions unit while fixing the two fixed portions, moving a heat fusion unit from a side of the first heat fusion region toward a base end side of the optical fiber, and pushing a heat fusion portion of the optical fiber in a direction of shortening a length of the heat fusion portion, to form a second heat fusion region continuous to the first heat fusion region and in which the air holes of the optical fiber disappear; and removing the first heat fusion region by cutting the optical fiber within the second heat fusion region after the second heat fusion forming.

Optical fiber end processing method and optical fiber end processing apparatus and optical fiber end

There is provide an optical fiber end processing method, for processing an end portion of an optical fiber having a core and a clad surrounding the core, comprising: fixing two places of the optical fiber; firstly heating a part at a tip end side of the optical fiber between fixed parts fixed at two places, thereby melting the optical fiber at the heated part at the tip end side; secondly heating a part at a base end side of the optical fiber between the fixed parts away from the heated part at the tip end side in a state that the optical fiber is fixed at two places, thereby forming an expanded core region which is formed by expanding a diameter of the core by diffusing the dopant included in the optical fiber; and removing at least the heated part at the tip end side.

An optical fiber that has no bubbles in the ultraviolet ray curable resin filled inside the air holes to seal the end parts thereof, an end part processing method of the optical fiber, and an end part processing apparatus of the optical fiber, are provided. In an end part processing method of an optical fiber that is comprised of a core and a cladding formed around the core, the cladding having a refraction index lower than that of the core and has a plurality of air holes formed therein along the axis of the core, wherein the end part process of the optical fiber is to form sealed portions on the ends of the air holes by sealing them with ultraviolet ray curable resin, the method is characterized in that the sealed portion is formed by heating the end of the optical fiber.

Optical fiber, end part processing method of optical fiber, and end part processing apparatus of optical fiber

Optical fiber, optical fiber connecting method, and optical connector

An optical fiber coiled cord having a coil construction in which an optical fiber cord is spirally bent to obtain lengthwise stretchability, wherein the fiber coiled cord is provided with a stretch length control member which restricts lengthwise elongation.

Optical fiber coiled cord

An optical fiber cord which is a single core optical fiber cord having an outer diameter of 1.2 mm or less, and has a structure in which an optical fiber core wire having a resin coating is provided at the center, a tensile-strength-fiber layer is provided around the outer periphery of the optical fiber core wire, and a coating layer is further provided around the outer periphery of the tensile-strength-fiber layer, wherein the coating layer is composed of a non-halogen fire-retardant resin, is disclosed. This optical fiber cord has excellent fire retardant, mechanical and handling properties, although the outer diameter thereof is made smaller.

Optical fiber cord

A single core optical fiber cord having an outer diameter of 1.2 mm or less, and having a structure in which an optical fiber core wire having a resin coating provided at the center, a tensile-strength-fiber layer around the periphery of the optical fiber core wire, and a coating layer around the outer periphery of the tensile-strength-fiber layer is provided. The coating layer can be composed of a non-halogen fire-retardant resin. The optical fiber cord has excellent fire retardant, mechanical and handling properties, although the outer diameter thereof is 1.2 mm or less.

An optical fiber distribution module having a connection board, optical connector adaptors and a storage section is provided. An array of the optical connector adaptors forms the connection board, where the optical connectors connect in-use optical fibers. The storage section, located in a separate section of the module, stores optical fibers which are not-in use. The optical fiber distribution module also includes a plurality of cord sorting boards having a plurality of fiber cord passageways. The fiber cord passageways are configured to accommodate and retain at least one optical fiber such that the optical fiber is arranged between the connection board and the storage section. In addition, both the in-use and not-in use optical fibers insert into the fiber cord passageway. The in-use optical fibers connect to the optical connector adaptors and the not-in use optical fibers are stored in the storage section as the in-use optical fibers and the not-in use optical fibers are inserted within the fiber cord passageways.

Optical fiber distribution module for holding an optical fiber cord and fiber distribution system using optical fiber cords

Metal filaments such as steel wires which has Young's modulus of 10,000 kg/mm,are provided longitudinally on a UV curable resin coated optical fiber. A resin covering layer is then formed on a resultant structure by coating ultraviolet curing resin and then curing the resin, whereby resulting in an extremely small optical fiber cord having a finished diameter of about 250 &mgr;m.

Optical fiber cord, ribbon cord using the same and ribbon cord branch line

A mono-fiber type optical fiber cord comprising: a coated optical fiber which is an optical fiber with a fiber coat therearound, a synthetic resin coat having a substantially rectangular sectional surface for further covering the coated optical fiber, and a reinforcing member within the coat for coated optical fiber, wherein the reinforcing member is located along one of the shorter sides of the coat in the substantially parallel direction with the shorter sides in such a manner as to be embedded along the longitudinally extending direction of the coated optical fiber. An optical cord ribbon is formed by mutually bonding the longer sides of the adjacent substantially rectangular sectional surfaces of a plurality of the mono-fiber type optical fiber cords, and thereafter by coating the external surface of the thus aligned optical fiber cords by a bundling coating method.

Optical fiber cord and optical cord ribbon

There is disclosed a transmission line switching apparatus comprising a coupling board having a first surface adapted to be connected a first line and a second surface adapted to be connected a second line, adjusting means having a line length adjusting unit for handling surplus portions of the second lines and switching means for changing the connection between the first and second lines, and partition means for dividing the second surface of the coupling board into a plural rows.

Transmission line switching apparatus

Growing community of inventors

Tokyo, Japan

Masao Tachikura