Fujikura Limited

Takayuki Kitamura

Sho Endo

Akihito Imase

Tatsuya Kishi

Kenichi Okada

Hiroshi Matsui

Nobuo Tanabe

Ryo Maruyama

Hiroki Usui

Munehisa Fujimaki

Takeshi Kizaki

A method for manufacturing an optical fiber includes: drawing an optical fiber from an optical fiber preform in a drawing furnace; and cooling the optical fiber in an annealing furnace. When the optical fiber enters the annealing furnace, a temperature difference between a temperature of the optical fiber and a fictive temperature of glass in a core of the optical fiber is 300&#xb0; C. or less. The optical fiber is cooled for 0.01 seconds or more in the annealing furnace so that the temperature of the optical fiber becomes 1300&#xb0; C. or more and 1800&#xb0; C. or less.

Method for manufacturing optical fiber

An optical fiber production method includes: drawing an optical fiber preform in a drawing furnace; and cooling the optical fiber. The optical fiber is passed through a plurality of annealing furnaces while the optical fiber is cooled. While the optical fiber is cooled, temperatures of the annealing furnaces are set such that the temperature difference is within a range between and including an upper limit and a lower limit of a temperature difference between a temperature of the optical fiber and a fictive temperature of glass constituting a core of the optical fiber at which an increase of a transmission loss of the optical fiber when the fictive temperature of the glass is decreased is less than 0.001 dB/km.

Optical fiber production method

An optical fiber production method includes: drawing an optical fiber from an optical fiber preform; and cooling the optical fiber. When in the cooling process, the optical fiber is passed through a plurality of annealing furnaces and Equation (1) is held. A time constant of relaxation of a structure of glass forming a core in the optical fiber is &#x3c4;(T). A temperature of the optical fiber at a point in time when the optical fiber is delivered into an nth annealing furnace from an upstream side is T. A fictive temperature of glass forming the core at the point in time when the optical fiber is delivered is T. A fictive temperature of glass forming the core after a lapse of time &#x394;t from the point in time when the optical fiber is delivered is T.20&#xb0; C.&#x3c;=()exp(&#x2212;&#x394;/&#x3c4;())&#x3c;100&#xb0; C.&#x2003;&#x2003;(1)

An optical fiber production method includes: drawing an optical fiber from an optical fiber preform in a drawing furnace; cooling the optical fiber in an annealing furnace; and delivering the optical fiber into the annealing furnace, and controlling a temperature difference between a temperature of the optical fiber and a fictive temperature of glass forming a core included in the optical fiber to be higher than 20&#xb0; C. and lower than 100&#xb0; C.

The refractive index of the inner core partin a region in contact with the boundary of the outer core partis higher than the refractive index of the outer core part. The refractive index of the outer core partis gradually decreased from the inner circumferential side to the outer circumferential side. The refractive index of the inner cladding partis equal to the refractive index of the outermost circumferential part of the outer core partand not greater than the refractive index of the outer cladding part

Optical fiber

An optical fiber includes a core and a cladding surrounding an outer periphery of the core and has a refractive index profile in which a relative refractive index difference with respect to a distance r from a center of the core is represented by &#x394;(r), where a value of A represented by(&#x394;()&#x2212;&#x394;())(&#x394;()&#x2212;&#x394;())&#x2003;&#x2003;(Formula 1)is 0.3%&#xb7;&#x3bc;m or less, where a unit of r is &#x3bc;m, a unit of a relative refractive index difference &#x394;(r) is %, &#x394;(r)=&#x2212;0.064r+0.494, and MFDis a mode field diameter at a wavelength of 1.31 &#x3bc;m.

Optical fiber and method of manufacturing the same

An optical fiber including a core and a cladding including an inner cladding layer and an outer cladding layer is provided. The refractive index of the core &#x394;1, the refractive index of the inner cladding layer &#x394;2, and the refractive index of the outer cladding layer &#x394;3 have a relationship denoted by the following expressions: &#x394;1max&#x3e;&#x394;2min and &#x394;1max&#x3e;&#x394;3, and 0.01%&#x3c;|&#x394;2min&#x2212;&#x394;3|&#x3c;0.03%. An outer circumference radius r1 of the core, an outer circumferential radius r2 of the inner cladding layer, and an outer circumferential radius r3 of the outer cladding layer have a relationship denoted by the following expressions: r1&#x3c;r2&#x3c;r3, and 0.2&#x2266;r1/r2&#x2266;0.5. A cable cut-off wavelength &#x3bb;cc 1260 nm or less. A mode field diameter at a wavelength of 1310 nm is 8.6 &#x3bc;m or more and 9.5 &#x3bc;m or less.

An optical fiber includes a core, and a clad surrounding an outer circumference of the core, in which a first relative refractive index difference &#x394;1a is greater than 0, a second relative refractive index difference &#x394;1b is greater than 0, the first relative refractive index difference &#x394;1a is greater than the second relative refractive index difference &#x394;1b, the first relative refractive index difference &#x394;1a and the second relative refractive index difference &#x394;1b satisfy a relationship denoted by the following expression: 0.20&#x2266;(&#x394;1a&#x2212;&#x394;1b)/&#x394;1a&#x2266;0.88, and a refractive index profile &#x394; of the core in an entire region of a section of 0&#x2266;r&#x2266;r1 as a function &#x394;(r) of a distance r from a center of the core in the radial direction is denoted by the following expression: &#x394;(r)=&#x394;1a&#x2212;(&#x394;1a&#x2212;&#x394;1b)r/r1.

Optical fiber and manufacturing method thereof

An apparatus for manufacturing a glass perform, includes: a dummy tube section, a reservoir portion, and a cooling portion; and a glass tube section in which particles of an alkali metal compound or an alkaline earth metal compound which have flowed into the glass tube section from the dummy tube section are heated by a second heat source which performs traverse, and oxides of the particles being deposited on an inner wall and dispersed in the glass tube section. In the cooling portion of the dummy tube section, vapor of the alkali metal compound or the alkaline earth metal compound generated by heating of a first heat source is cooled and condensed by a dry gas flowing into the dummy tube section, and thereby the particles are generated.

Apparatus and method for manufacturing glass preform

A method of manufacturing a glass preform is provided. The method including, vaporizing an alkali metal compound or an alkali earth metal compound and being brought the alkali metal compound or the alkali earth metal compound into contact with a hydroxyl group on a surface of porous silica glass and dehydrating the porous silica glass, and sintering the dehydrated porous silica glass and forming a transparent glass body.

Method of manufacturing glass preform

An optical fiber is provided. The optical fiber has a refractive index profile that includes a central core, an inner cladding layer, a trench layer, and an outer cladding layer. A trench layer is provided with a reduced refractive index. The optical fiber has a large effective area without having an increase of a cutoff wavelength, and exhibits low macrobending loss.

A photoelectric conversion element modulecomprises a plurality of photoelectric conversion elementseach having a first electrodeand a second electrodethat oppose each other, and a conductive memberelectrically connecting the plurality of photoelectric conversion elementsto each other; the plurality of photoelectric conversion elementsare arranged in planar form such that directions from the first electrodestoward the second electrodesare the same; the first electrodeand second electrodehave extended portionsrespectively which extend to outside a region encompassed by an outer periphery of a sealing member; and in adjacent photoelectric conversion elementsA andB, the conductive memberconnects the extended portionof one of the photoelectric conversion elementsA and the extended portionof the other photoelectric conversion elementB; and the extended portionhas flexibility.

Photoelectric conversion element module and method for manufacturing photoelectric conversion element module

A glass preform manufacturing method, includes: preparing a glass element having a rough surface; turning a raw material of an alkali metal compound or a raw material of an alkaline earth metal compound into particles; depositing particles of the alkali metal compound or the alkaline earth metal compound on the rough surface of the glass element; oxidizing the particles of the alkali metal compound or the alkaline earth metal compound while diffusing alkali metal oxide or alkaline earth metal oxide in the glass element; and manufacturing a glass preform into which the alkali metal oxide or the alkaline earth metal oxide is doped.

Glass preform manufacturing method

A photoelectric conversion element of the present invention includes: a first electrode being linear; a second electrode; and an electrolyte. The first electrode and the second electrode are disposed via the electrolyte. The first electrode includes a first linear material which includes a copper wire and a metal coating which coats the copper wire and a dye-carrying porous oxide semiconductor layer disposed on an outer circumference of the first linear material.

Photoelectric conversion element

An electrolyte composition includes an ionic liquid and a solvent, wherein the solvent contains a material made of at least one of sulfolane and derivatives thereof, and a content of the material is 5 to 40 mass % of the total content of the electrolyte composition.

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Sakura, Japan

Takayuki Kitamura