Hitachi Cable, Inc.

Nippon Telegraph and Telephone Corporation

Hitachi Metals, Ltd.

Toyota Jidosha Kabushiki Kaisha

Toyota School Foundation

Kazumasa Ohsono

Bing Yao

Masao Tachikura

Yoshinori Kurosawa

Kanako Suzuki

Akihito Hongo

Toshio Kurashima

Yoshihisa Kato

Noribumi Shiina

Eiji Araki

Katumi Hiramatu

Seiji Kojima

Yoshikazu Namekawa

Hisanori Nakai

Tomoyuki Nisio

Hiroshi Ito

Daisuke Inoue

Akio Sato

Tadashi Ichikawa

Kenji Kawase

Masaru Ishikawa

Kazuo Hasegawa

Yoshihiro Nakatani

Kazuya Saito

Kohei Yanaka

Toshihiko Ishikawa

Kyoji Osozawa

Motoyoshi Nakamura

A multicore fiber includes cores located at vertexes of a polygonal ring and a cladding including sub medium regions and covering the cores. A refractive index of the cladding is lower than a refractive index of the cores and higher than a refractive index of the sub medium regions. The sub medium regions are arranged at positions to reduce a crosstalk between adjacent cores of the cores.

Multicore fiber

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 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

An optical fiber laser, according to the present invention, has an optical fiber including a core to which a rare earth element is added and a clad disposed around the core, and also has an excitation light source for emitting excitation light incident on a side of the optical fiber. The optical fiber has a corrugated shape on the outer circumference of the clad along the longitudinal direction thereof; and the optical fiber is wound in a spiral form and is bundled in such a way that adjacent sides of the clad are brought into contact with one another.

Optical fiber laser and exciting method using same

An optical connector according to the present invention comprises a ferrule and a V-groove board connected to the ferrule, wherein a first optical fiber and a second optical fiber being butt jointed in a V-groove formed in the V-groove board so as to be interconnected; the second optical fiber is connected to the first optical fiber through a refractive index matching material of cross-link curing type applied to an end surface on the V-groove board side of the first optical fiber; and spaces are provided in the V-groove so as to relax stress loaded on the refractive index matching material of cross-link curing type.

Optical connector

The optical fiberfor an optical fiber laser is provided with a rare earth element doped coredoped with a rare earth element, and a claddingformed at an outer periphery of the rare earth element doped core. In the optical fiberfor an optical fiber laser, the rare earth element doped coreis divided into a plurality of core regions&#x2212;1,along a longitudinal direction of the optical fiberand dopant concentrations of the rare earth element in respective core regions&#x2212;1,are different from each other, in order to flatten a temperature distribution of the optical fiberalong the longitudinal direction.

Optical fiber for an optical fiber laser, method for fabricating the same, and optical fiber laser

To provide a low-cost, high reliability and high-powered operation enabled optical fiber laser, in the optical fiber laser for oscillating a laser light by introducing an excitation light for exciting the rare earth elements into the optical fiber doped partially by the rare earth elements, the optical fiber is wrapped around the base member, and one part of the outer circumferential area of the wrapped optical fiber is processed in order to form a flat surface, and one face of the prism is made contacted to the flat surface, and the excitation light is introduced to another surface of the prism.

Optical fiber laser

A cladding is provided at an outer periphery of a solid-core doped with rare earth ions, and a metal layer is formed to be adjacent to the cladding to provide an optical fiber for a fiber laser device. The metal layer having an inner metal layer and an outer metal layer is disposed along an entire length of the optical fiber for a fiber laser device. An exciting light is incident to the optical fiber for a fiber laser device, and the exciting light is reflection-excited to emit a high power laser oscillation light. A monitoring current is constantly flown into the metal layer. When the disconnection of the optical fiber for a fiber laser device is detected based on the monitoring current, the energization of the optical fiber for a fiber laser device is stopped.

Optical fiber for fiber laser device and fiber laser device using same

Optical fiber, optical fiber connecting method, and optical connector

An optical fiber includes a core, a clad having a plurality of air holes at a periphery of the core, and a hardening resin filled in a sealed portion at an end of the plurality of air holes. The hardening resin after hardening has a fill length of 7 mm to 8 mm. An optical fiber connection structure includes the optical fiber with an end face butt-connected to another optical fiber. An optical connector includes the optical fiber, and a ferrule to which the optical fiber is attached.

Optical fiber, optical fiber connection structure and optical connector

An optical fiber includes a core, a clad formed around the core, a plurality of holes being formed in the clad, and a UV curing optically-transparent resin which is filled in the holes and hardened. The UV curing optically-transparent resin has a Young's modulus of 8 to 500 MPa after hardening.

Optical fiber, end face structure of optical fiber assembly, and optical connector

An optical connector having: a ferrule into which a first optical fiber is inserted; an optical fiber connector disposed at an back end of the ferrule; and a cross-linkable refractive index matching member attached onto an end face on a back end side of the first optical fiber. The end face on the back end side of the first optical fiber and an end face of a second optical fiber to be inserted into the optical fiber connector from a back end side thereof are to be connected by a butting connection. The cross-linkable refractive index matching member is formed such that a cross-linkable refractive index matching agent is coated on the end face on the back end side of the first optical fiber, and the coated agent is cross-linked and hardened.

Optical connector and connection structure of optical fibers

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.

Growing community of inventors

Hitachi, Japan

Kazumasa Ohsono