Nippon Telegraph and Telephone Public Corporation

Sumitomo Electric Industries, Limited

Nippon Telegraph and Telephone Corporation

Nakahara Opto-Electronics Laboratories, Inc.

Nakahara Opto-Electronics

Other

Tdk Corporation

Motohiro Nakahara

Minoru Watanabe

Michihisa Kyoto

Koichi Arishima

Naoki Yoshioka

Fumiaki Hanawa

Tetsuo Miyajiri

Hiroyuki Suda

Hiroshi Yokota

Shuichi Shibata

Shoichi Suto

Shigeru Tanaka

Takashi Kikukawa

Hiroo Kanamori

Kenji Yokoyama

Hiroshi Takahashi

Masahiro Shinkai

Yasuyuki Inoue

Gotaro Tanaka

Shuzo Suzuki

Katsunari Okamoto

Motohaya Ishii

Masao Kawachi

Hiroki Hara

Takao Edahiro

Akimasa Kaneko

Toru Kuwahara

Shin Sumida

Masami Sasaki

Nobuo Inagaki

Senichi Suzuki

Fumihiro Ebisawa

Toshimi Habasaki

Kuninori Hattori

Tamio Tsurita

Hiroaki Yamada

Takashi Yoshida

Ryohei Fukuzaki

Tetsuo Miya

Kazuhiro Nakahara

Katsuya Ohtomo

Shohei Ogura

Shuji Tachi

Masahiro Shiotani

An optical component having an NA conversion function which enables arraying without lowering a product yield, with small size and a simple assembly process. There is provided an optical component using a capillary type lens array in which plural graded index lenses each of which is surrounded with glass capillary in all circumferential directions, in which a refractive index distribution constant of the plurality of graded index lenses at one end of the optical component in an optical axis direction of the graded index lens is smaller than a refractive index distribution constant of the plurality of graded index lenses at other end of the optical component in the optical axis direction of the graded index lens.

Optical component, optical connection component with graded index lens, and method of manufacturing optical component

A capillary-type lens array having an inorganic glass around a graded index lens, in which a plurality of the graded index lenses and the inorganic glass are physically fused.

Capillary-type lens array and capillary-type lens array composite component

An optical connection apparatus comprising a prism that extracts N&#xd7;M beams of outgoing light from an optical circuit, a two-dimensional GRIN lens array of N&#xd7;M GRIN lenses, a spacer, having a thickness according to the optical path length in the prism, that transmits N&#xd7;M outgoing beams from the two-dimensional GRIN lens array, and a two-dimensional fiber array that causes the N&#xd7;M beams to be incident on optical fibers, the ends of optical fibers being disposed at the focal point of each of the beams transmitted through the spacer.

Optical connection apparatus

A perforated quartz glass tube includes a jacket tube containing a quartz glass material, a plurality of cylindrical glass tubes which are inserted into a pore region of the jacket tube along an axial direction of the jacket tube, and contain a quartz glass material having a softening point higher than a softening point of the jacket tube, and a gap member which is inserted into a gap between the cylindrical glass tubes and a gap between the jacket tube and the cylindrical glass tube, and contains a quartz glass material having a softening point lower than a softening point of the cylindrical glass tube.

Perforated quartz glass tube and method for manufacturing perforated quartz glass tube

A first disclosure is an optical fiber member equipped with two holding members that hold an optical fiber such that an end surface of the optical fiber is located on one end and a curving portion having a coat of the optical fiber is curved to be extended at another end; the holding members are provided with holding flat portions that sandwich an end portion of the optical fiber where the coat is removed such that the end surface of the optical fiber is located on the one end; at least any of the holding flat portions has an aligning groove to fix a position of the end portion of the optical fiber; the holding member is provided with a curved surface at a position adjacent to the curving portion in the extending direction D; and the two holding members are equal in thermal expansion coefficient.

Optical fiber member and optical fiber holder

In a light waveguide circuit including a plurality of waveguides having different length, a material (,) having a temperature coefficient of a refractive index including a symbol different from that of a temperature coefficient of an effective refractive index of the waveguide (,) is charged into a groove (,) formed by removing the upper clad and the core from the waveguide (,), or a groove (,) formed by removing the upper clad, the core and the lower clad from the waveguide (,). A difference in length of the removed portions between adjacent waveguides is proportional to a difference in length of the waveguides which were not removed and remained.

Optical waveguide circuit, its manufacturing method and optical waveguide module having the optical waveguide circuit

A method for producing a glass preform for an optical fiber comprising forming a fine glass particle mass by flame hydrolysis of a glass raw material, dehydrating the fine glass particle mass in an oxygen atmosphere containing chlorine or a chlorine-containing compound at such temperature that the soot preform is not considerably shrunk and heating the soot preform at a temperature at which the soot preform is sintered and made transparent, the glass preform produced by which method contains less hydroxyl groups, structural defects and an optical fiber fabricated from said glass preform has stable light transmission characteristics for a long time.

Method for producing glass preform for optical fiber

A method for producing a glass preform for optical fibers in which fluorine is efficiently incorporated into the preform without incorporation of Fe or Cu. A fine glass particle mass, made primarily of quartz, is converted into transparent glass by heating it in a gas atmosphere containing at least a fluorine-based compound gas and a chlorine-based compound gas. The preferred heating range is 1,100.degree. to 1,400.degree. C.

Method for production of glass preform for optical fibers

A quartz optical fiber comprising a core having a higher refractive index and made of pure quartz containing fluorine and phosphorus pentoxide and a cladding having a lower refractive index, a weight ratio of fluorine and phosphorus pentoxide in the core being larger than 1 (one), which is substantially free from unstability of the glass structure.

Quartz glass optical fiber

In an optical fiber preform fabrication method having the steps of decomposing a glass raw material in a flame so that fine glass particles are produced; depositing the fine glass particles on a seed rod to form a porous preform; and consolidating the porous preform into a transparent optical fiber preform, use is made of a burner having a raw material supply orifice for supplying the glass raw material and a plurality of flame forming orifices deposed around the raw material supply orifice sequentially for forming a plurality of flames, respectively. The flame speed V.sub.k of a kth flame, the flame speed V.sub.k+1 of a (k+1)th flame surrounding outwardly of the kth flame and the flow speed Vm of the glass raw material are determined in a suitable manner. The glass raw material is supplied to the multi-flame produced by the burner in which the kth flame is positioned rearwardly of the (k+1)th flame to synthesize the fine glass particles.

Method, apparatus and burner for fabricating an optical fiber preform

In an optical fiber preform fabrication method having the steps of decomposing a glass raw material in a flame so that fine glass particles are produced; depositing the fine glass particles on a seed rod to form a porous preform; and consolidating the porous preform into a transparent optical fiber preform, use is made of a burner having a raw material supply orifice for supplying the glass raw material and a plurality of flame forming orifices disposed around the raw material supply orifice sequentially for forming a plurality of flames, respectively. The flame speed V.sub.k of a kth flame, the flame speed V.sub.k+1 of a (k+1)th flame surrounding outwardly of the kth flame and the flow speed Vm of the glass raw material are determined in a suitable manner. The glass raw material is supplied to the maluti-flame produced by the burner in which the kth flame is positioned rearwardly of the (k+1)th flame to synthesize the fine glass particles.

A device is disclosed for supplying a glass raw material gas in the form of the mixed gas consisting of the glass raw material gas and the carrier gas to a vapor deposition device for producing a preform of an optical fiber, the supply device including a secondary raw material container having a pressurizable interior and provided adjacent to a main raw material container. The bottoms, or areas near the bottoms, of the two containers are interconnected via a pipe including at a mid portion thereof a switching valve and a device for adjusting the flow rate of the raw material liquid between the two containers. Liquid level detectors are provided in one or both containers to maintain the constant volume of the liquid raw material so as to provide a constant state inside the main raw material container. The operation of this device can easily be entirely automated.

Raw material supply device

A process for producing an optical fiber preform in a muffle furnace by hydrolyzing a gaseous glass forming material with a flame from an oxyhydrogen burner and depositing the resulting soot in a rod shape and an apparatus therefor are described, wherein a gas is supplied to the muffle furnace other than from said burner, and the volume supply of said gas is held constant by controlling the amount of a control gas supplied into an intermediate portion of an exhaust pipe through which the gases formed in the muffle furnace and the fine glass particles that do not deposit in a rod shape are discharged.

System for producing an optical fiber preform with gas volume control

A process and apparatus for producing an optical fiber preform by oxidizing a gaseous glass forming material with a flame from a burner and depositing the resulting soot in a rod form are described, wherein two signal beams, supplied by splitting a light beam, are projected in a direction normal to the direction in which the preform grows and are directed into the space between the burner and the deposition face of the preform, and they are positioned so that one beam partially contacts the deposition face of the preform, while the other beam is directed to pass between the burner and the deposition face, and the distance between the burner and the deposition face is controlled such that the ratio of the intensity of the two beams passing through the space between the burner and the deposition face is held constant.

Process for producing optical fiber preform and apparatus therefor

Manufacturing method of doped silica glass suitable for optical fiber wherein quartz powder or SiO.sub.2 glass fine particles are exposed to a gas for producing the doped silica glass containing SiCl.sub.4, a gaseous additive and water vapor (H.sub.2 O) to add the dopant to the glass body, and then the resulting glass body is fused at a high temperature, thereby producing a transparent doped silica glass in which the production of the glass particles, the addition of the dopant, and the vitrification of the glass body are carried out by separate steps under respective suitable conditions. The manufacturing speed is remarkably increased because of the separate steps. The content of the dopant is not limited, but can be adjusted with any desired amount by changing the reaction time of dissolution. Dopant components like PbO.sub.2, SnO.sub.2, ZnO which were typically not added to the glass body can now be added thereto. Also, a method of manufacturing an optical fiber preform is disclosed wherein the doped silica glass is deposited and fused on a starting material which is inclined by an angle within a range of 5.degree.-90.degree. with respect to a blow-off direction of the flow of the doped silica glass to form a transparent doped silica glass body having a uniform outer diameter and a uniform boundary surface at a high synthesizing speed. This latter method aids mass production of optical fibers at low cost.

Fabrication methods of doped silica glass and optical fiber preform by

Growing community of inventors

Mito, Japan

Motohiro Nakahara