Hitachi Cable, Inc.

Nippon Telegraph and Telephone Corporation

Hitachi Metals, Ltd.

Toyota Jidosha Kabushiki Kaisha

Toyota School Foundation

Bing Yao

Kazumasa Ohsono

Akihito Hongo

Masao Tachikura

Seiji Kojima

Toshio Kurashima

Yoshinori Kurosawa

Eiji Araki

Katumi Hiramatu

Hisanori Nakai

Hiroshi Ito

Daisuke Inoue

Kanako Suzuki

Akio Sato

Tadashi Ichikawa

Yoshihisa Kato

Kazuo Hasegawa

Noribumi Shiina

Shinji Hinoshita

Kazuya Saito

Kohei Yanaka

Tetsuya Sukegawa

Tomokazu Hiyama

Shigeto Kobayashi

Natsuki Kamiya

The invention provides a resin-coated optical fiber, including at least: a glass optical fiber composed of a core and a clad for coating the core; a primary layer made of UV-curing resin in contact with the glass optical fiber; and a secondary layer made of the UV-curing resin disposed on an outer periphery of the primary layer, wherein the primary layer has a two-layer structure of an inner layer in contact with a surface of the clad, and an outer layer for coating the inner layer, wherein the UV-curing resin of the inner layer has a Young's modulus of 0.9 MPa or more and 3.0 MPa or less at room temperature in a film state based on JIS standard K7113, and the UV-curing resin of the outer layer has a Young's modulus of 0.1 MPa or more and 0.7 MPa or less at room temperature in a film state based on JIS standard K7113.

Resin-coated optical fiber

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 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

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

Growing community of inventors

Hitachi, Japan

Bing Yao