Sumitomo Electric Industries, Limited

Katsuyuki Tsuneishi

Takashi Yamazaki

Ichiro Tsuchiya

Toru Yamanishi

Katsuya Nagayama

Kazuya Kuwahara

Masaaki Yoshida

Takashi Sato

Toshiaki Kakii

Tatsuya Konishi

Tomoyuki Hattori

Makoto Shimizu

Satoshi Yoshikawa

Kohei Kobayashi

Yasuo Matsuda

Toshiki Taru

Hiroshi Kohda

Iwao Okazaki

Yuji Kubo

Shigeru Ito

Yuji Kameo

Hiroaki Ohta

Motohide Yoshida

Katsuzo Mukai

Hideo Miyaki

Yutaka Iwamura

Masao Koida

Masakatsu Sugai

Takaharu Sato

A method of manufacturing an optical fiber with a hole from a preform having a through hole is disclosed. The manufacturing method includes placing a preform in a drawing furnace, forming an optical fiber by melting and drawing the preform in the drawing furnace while a gas is introduced into the through hole, capturing an image of the optical fiber drawn from the preform, and measuring a hole diameter of the optical fiber based on an image captured in the capturing of the image and controlling a pressure of the gas introduced into the through hole based on a measurement result. In the capturing of the image, when the optical fiber deviates, a predetermined countermeasure is taken to make the image clear, and the image is maintained in a clear state.

Method of manufacturing optical fiber and apparatus for manufacturing optical fiber

A furnace gas supply apparatus configured to supply gas into a drawing furnace, includes: a first flow channel introducing the gas from a predetermined first gas inlet to flow the gas from a predetermined first gas outlet toward a gas storage portion, and a second flow channel introducing the gas stored in the gas storage portion from a predetermined second gas inlet to flow the gas from a predetermined second gas outlet toward a furnace core tube of the drawing furnace, in which the gas storage portion is provided between the first gas outlet and the second gas inlet, and in which an opening position of the second gas inlet is provided at a position different from an opening position of the first gas outlet.

Furnace gas feeding device, optical fiber production device, and optical fiber production method

Capacity of space in a drawing furnace is decreased so as to reduce variations in pressure in the furnace and also the side of an insertion port of a glass perform is stably sealed. When drawing is started, an outer peripheral surface of the optical fiber glass preformis sealed with a first seal partof the seal mechanism. After a vicinity of a taper part of the optical fiber glass preformstarts to pass through the first seal part, switching to a second seal partarranged above the first seal partis performed, and an outer peripheral surface of a sleeve memberfixed so as to surround an outer periphery of the dummy rodis sealed with the second seal part

Optical fiber drawing method and optical fiber drawing apparatus

A fiber drawing method according to the present invention is a drawing method of optical fiber for drawing an optical fiber from one end of a fiber preform by softening with heat, wherein the fiber preform is set in a semi-closed space opening in part at a lower end in a fiber drawing furnace, the fiber preform is heated by a heater disposed on the lower end side of this semi-closed space and fiber drawing is carried out with adjusting a quantity of heat dissipation from the upper portion of this semi-closed space.

Optical fiber drawing method and drawing furnace

The heat-resistant coated optical fiber in accordance with the present invention comprises a coating portion , coated on the outer periphery of an optical fiber , comprising a first coating layer consisting of aromatic polyimide resin, a second coating layer consisting of silicone resin, and a third coating layer consisting of moisture-resistant resin with a heat resistance equivalent to that of the first coating layer , e.g., PFA.

Heat resistant optical fiber core

There is provided an optical fiber drawing furnace capable of drawing an optical fiber having small non circularity, which drawing furnace includes a muffle tube, in which an optical fiber preform is supplied, a heater surrounding the muffle tube, a plurality of electrode connecting portion extending from the heater, a plurality of electrodes connected to electrode connecting portions, and in conjunction therewith to an electric power source, and unifying means for unifying the temperature distribution along the circumferential direction.

Optical fiber drawing furnace with a zig zag heating element

Method and apparatus for fabricating coated optical fiber, and coated optical fiber

In a drawing method and drawing apparatus according to the present invention, a forward end portion of an optical fiber glass preform is heated and melted while the glass preform is fed into a drawing furnace 3 so that an optical fiber is drawn, and the optical fiber glass preform is heated in a position just above the drawing furnace to make the surface of the glass preform clean.

Cleaning a glass preform with a high temperature inert gas during the

A method and apparatus are provided for detecting irregular portions of an optical fiber which arise due to microscopic bubbles, bruises, and the like during an optical fiber drawing process. The present invention operates by varying the pulling rate of a pulling capstan based on feeding back measurements of the external diameter of the optical fiber to the pulling capstan. The ratio of a given pulling rate variation to a predetermined time period is then computed. The computed ratio is then compared to a previously specified value.

Method and apparatus for detecting irregular part of optical fiber

An optical fiber drawing apparatus which includes a heating furnace which fuses a forward end of an optical fiber preform for drawing an optical fiber, and a screening portion which applies tension to the optical fiber through in-line, for guarantee of its strength. The screening portion further includes a suction device disposed along a passage of the optical fiber running through it for sucking in the optical fiber.

Optical fiber drawing apparatus

A method for producing an optical fiber which comprises steps of:

Method for producing optical fiber

A method and apparatus for coating optical transmission glass fibers with a resinous composition. A vessel is provided through which a glass fiber is drawn. While it is being drawn through the vessel, the fiber is spun, and a resin coating is applied. In order to maintain the air pressure within the vessel fairly constant, an exhaust vent is provided through which excess particles of the resinous composition may escape. Turbulence is thus substantially reduced preventing the fiber from swinging and allowing the particles to be sprayed smoothly. Further, the particles may be electrically charged so that they are both attracted to the optical fiber and repel one another during flight. The invention employs both of these features to produce a uniform coat on an optical transmission glass fiber.

Growing community of inventors

Yokohama, Japan

Katsuyuki Tsuneishi