Nippon Telegraph and Telephone Corporation

Hitachi Cable, Inc.

Hitachi Metals, Ltd.

Katumi Hiramatu

Masao Tachikura

Toshio Kurashima

Kazumasa Ohsono

Yoshinori Kurosawa

Eiji Araki

Bing Yao

Hisanori Nakai

Kenji Kawase

Yoshikazu Namekawa

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

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

Growing community of inventors

Tokyo, Japan

Katumi Hiramatu