Fujikura Limited

Manabu Kudoh

Kazuhiko Aikawa

Kazuyuki Hayashi

Katsuaki Izoe

Takashi Tsumanuma

Tomoaki Toriya

Katsuyuki Seto

Ken-ichi Nakatate

Yutaka Endoh

Koji Omichi

Yoshihiro Terada

Naoki Shamoto

Masami Miyachi

Masahiro Asano

A polarization-maintaining optical fiber of the present invention includes a core, a pair of stress-applying parts provided on both sides of the core, and a cladding surrounding the core and the stress-applying parts, and is used in a wavelength range of 400 to 680 nm. The diameter of the cladding is 125 &#x3bc;m, the diameter of the stress-applying part is 33 to 37 &#x3bc;m, a distance between the pair of stress-applying parts is 8.6 to 15.4 &#x3bc;m, a relative refractive index difference between the core and the cladding is 0.35 to 0.45%, and a cut-off wavelength is less than or equal to 400 nm.

Polarization-maintaining optical fiber

A low-loss optical fiber over wide wavelength range includes a transmission loss of less than or equal to 40 dB/km in a whole wavelength range of 400-1400 nm, and being manufactured by drawing an optical fiber preform including a core composed of a silica glass having a hydroxyl-group concentration of less than or equal to 1 ppm and a cladding composed of a silica glass having a fluorine concentration of more than or equal to 3.2 wt %.

Low-loss optical fiber over wide wavelength range and method of manufacturing the same

The polarization-maintaining fiber of the invention includes a core () made of germanium doped silica glass; a stress-applying part () made of boron doped silica glass; a cladding () made of pure silica glass; and a polyimide coating layer () with a thickness of 10 &#x3bc;m or less that surrounds the outer periphery of the cladding ().

Polarization-maintaining fiber and optical fiber sensor using same

An optical fiber bundle unit is provided for transmitting ultraviolet light in which the increase of the transmission loss caused by radicals generated in the optical fiber by irradiation or transmission of ultraviolet light is suppressed and a stable energy state is maintained even after the irradiation or transmission of ultraviolet light. The optical fiber bundle unit for transmitting ultraviolet light includes an optical fiber bundle and a sealed container in which the optical fiber bundle is held. A diffusion of hydrogen gas is suppressed by putting the optical fiber bundle pretreated in a hydrogen atmosphere into the sealed container, followed by filling the sealed container with a mixed gas including a hydrogen gas and a gas which is not combustible, will not support combustion, and will not explode.

Optical fiber bundle unit for transmitting ultraviolet light

A radiation resistant single-mode optical fiber has a core and a cladding, each made of fluorine-doped silica glass, in which a chlorine concentration of the core is at least 0.01 ppm, a relative refractive index difference of the core based on the refractive index for silica is between &#x2212;0.30% and &#x2212;0.10%, a relative refractive index difference of the core based on the refractive index for the cladding is between 0.3% and 0.5%, a cutoff wavelength is 1.27 &#x3bc;m or below, and a bending loss at a wavelength of 1.3 &#x3bc;m and a bending diameter of 20 mm is 0.5 dB/m or less.

Radiation resistant single-mode optical fiber and method of manufacturing thereof

A polarization-maintaining optical fiber comprises: a core; a pair of stress-applying parts disposed one at each side of the core; and a cladding which surrounds the core and the stress-applying parts; wherein when the polarization-maintaining optical fiber is used at a wavelength of 0.81 &#x3bc;m to 0.87 &#x3bc;m, a cut-off wavelength measured with a fiber length of 2 m is longer than the wavelength used and polarization crosstalk when a fiber having a length of 1,000 m is wound on a reel having a diameter of 40 mm is equal to or less than &#x2212;35 dB/100 m.

Polarization-maintaining optical fiber and optical fiber gyro

An optical fiber bundle unit is provided for transmitting ultraviolet light in which the increase of the transmission loss caused by radicals generated in the optical fiber by irradiation or transmission of ultraviolet light is suppressed and a stable energy state is maintained even after the irradiation or transmission of ultraviolet light. The optical fiber bundle unit for transmitting ultraviolet light includes an optical fiber bundle and a sealed container in which the optical fiber bundle is held, wherein the sealed container contains a hydrogen gas.

Growing community of inventors

Sakura, Japan

Manabu Kudoh