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公开(公告)号：CA2116701C
公开(公告)日：2003-12-30
申请号：CA2116701
申请日：1994-03-01
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： ITO MASUMI , DANZUKA TOSHIO , OHGA YUICHI , HOSHINO SUMIO , TSUCHIYA ICHIRO
IPC: C03B8/04 , C03B20/00 , C03B37/014 , G02B6/00 , C03B37/018 , G02B6/18
Abstract: The present invention relates to an improved process for providing the production of a glass preform for an optical fiber which includes substantially no bubbles therein and also which has a substantially uniform shape. The process for the production of a glass preform which comprises at least silica for an optical fiber is comprised of producing a body comprising a rod on which fine glass particles are deposited, preferably by a vapour phase reaction and heating the body to vitrify the body under a reduced atmosphere or a vacuum so that the glass preform is produced. The process includes a first heating step of degassing the body at a first heating temperature, a second heating step of shrinking the body at a second heating temperature which is higher than the first heating temperature and which is lower than a third heating temperature, and a third heating step of vitrifying the shrunken body at the third temperature which corresponds to a vitrification temperature of the fine glass particles so as to produce the glass preform.
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公开(公告)号：DE69328572T2
公开(公告)日：2001-01-04
申请号：DE69328572
申请日：1993-07-08
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： HOSHINO SUMIO , DANZUKA TOSHIO , OHGA YUICHI , ITO MASUMI , MUKAI KATSUZO
IPC: C03B37/027 , C03B20/00 , C03B37/012 , C03B37/014 , C03B37/018 , G02B6/00
Abstract: An apparatus for drawing a glass preform for an optical fiber is disclosed.
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公开(公告)号：GB2307907B
公开(公告)日：1999-07-28
申请号：GB9625272
申请日：1996-12-04
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： HOSHINO SUMIO , OHGA YUICHI , ITO MASUMI , DANZUKA TOSHIO , SAITO TATSUHIKO
IPC: C03B23/047 , C03B37/012 , C03B37/014 , C03B37/025 , C03B37/027 , C03B37/07
Abstract: The present invention relates to a method for precisely elongating a glass preform of an optical fiber body having a desired outer diameter. In this method, a predetermined part of the glass preform is elongated as tensile stress is applied to one end of the glass preform while a predetermined part of the glass preform is heated and softened successively from one end toward the other end of the glass preform. In this elongating operation, while the outer diameter of the softening portion of the glass preform is measured, the tensile stress is adjusted such that the outer diameter of the softening portion coincides with a preset value of the control outer diameter. In particular, this method is characterized in that the preset value of the control outer diameter is changed at least during a predetermined period until termination of elongation or during a predetermined period from the start of elongation.
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公开(公告)号：DE69410704D1
公开(公告)日：1998-07-09
申请号：DE69410704
申请日：1994-06-17
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： ITO MASUMI , HOSHINO SUMIO , DANZUKA TOSHIO
IPC: C03B37/014
Abstract: A method of manufacturing an optical fiber in which the deviation of a cutoff wavelength from a design value can be minimized. It is found that, upon diameter reduction of a porous core glass body by heat treatment, when the diameter reduction ratio is set to a value larger than 0.90, a "spike" in the refractive index distribution curve of a core can be prevented, and the deviation of the cutoff wavelength from the design value can be minimized. Therefore, there is provided a method comprising the first step of depositing fine SiO2 particles and fine GeO2 particles, which are produced by a core formation burner (31), to grow a porous core glass body (21) from a distal end of a rotating starting rod (16) in an axial direction, the second step of performing diameter reduction by heating the grown porous core glass body by heating means (33) while growing the porous core glass body, and the third step of depositing fine SiO2 particles produced by a cladding formation burner (32) to form a porous cladding glass layer on an outer surface of the diameter-reduced porous core glass body while performing growing and diameter reduction of the porous core glass body, wherein an outer diameter of the porous core glass body after the second step of performing diameter reduction is larger than 0.90 times an outer diameter before diameter reduction.
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公开(公告)号：AU7405496A
公开(公告)日：1997-06-12
申请号：AU7405496
申请日：1996-11-28
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： HOSHINO SUMIO , OHGA YUICHI , ITO MASUMI , DANZUKA TOSHIO , SAITO TATSUHIKO
IPC: C03B23/047 , C03B37/012 , C03B37/014 , C03B37/025
Abstract: The present invention relates to a method for precisely elongating a glass preform of an optical fiber body having a desired outer diameter. In this method, a predetermined part of the glass preform is elongated as tensile stress is applied to one end of the glass preform while a predetermined part of the glass preform is heated and softened successively from one end toward the other end of the glass preform. In this elongating operation, while the outer diameter of the softening portion of the glass preform is measured, the tensile stress is adjusted such that the outer diameter of the softening portion coincides with a preset value of the control outer diameter. In particular, this method is characterized in that the preset value of the control outer diameter is changed at least during a predetermined period until termination of elongation or during a predetermined period from the start of elongation.
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Patent Agency Ranking
公开(公告)号：DE69305229T2
公开(公告)日：1997-03-06
申请号：DE69305229
申请日：1993-05-24
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： AIKAWA HARUHIKO , NAGAYAMA KATSUYA , DANZUKA TOSHIO
Abstract: There is provided an apparatus for the production of a hermetically coated optical fiber in which a glass preform for an optical fiber is melt drawn in a melt drawing furnace to produce a bare optical fiber which is passed to a reactor where a feed gas is supplied and the bare optical fiber is coated with a thin carbon coating made from the feed gas by the Chemical Vapor Deposition method characterized in that the reactor comprises an upper portion to which the feed gas is supplied, a middle portion in which the CVD method is substantially carried out and a lower portion from which an exhausted gas is withdrawn, and a cross sectional area of the middle portion perpendicular to a longitudinal direction of the optical fiber is larger than that of the upper portion.
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公开(公告)号：DE69305229D1
公开(公告)日：1996-11-14
申请号：DE69305229
申请日：1993-05-24
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： AIKAWA HARUHIKO , NAGAYAMA KATSUYA , DANZUKA TOSHIO
Abstract: There is provided an apparatus for the production of a hermetically coated optical fiber in which a glass preform for an optical fiber is melt drawn in a melt drawing furnace to produce a bare optical fiber which is passed to a reactor where a feed gas is supplied and the bare optical fiber is coated with a thin carbon coating made from the feed gas by the Chemical Vapor Deposition method characterized in that the reactor comprises an upper portion to which the feed gas is supplied, a middle portion in which the CVD method is substantially carried out and a lower portion from which an exhausted gas is withdrawn, and a cross sectional area of the middle portion perpendicular to a longitudinal direction of the optical fiber is larger than that of the upper portion.
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公开(公告)号：CA2085198C
公开(公告)日：1996-10-01
申请号：CA2085198
申请日：1992-12-11
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： TSUCHIYA ICHIRO , DANZUKA TOSHIO , ITO MASUMI
IPC: C03B37/014 , G02B6/00
Abstract: A process for the vitrification of a porous glass preform for an optical fiber involves heating the preform under an increasing pattern of temperature in a vacuum furnace comprising a muffle tube. The increasing pattern is divided into two steps consisting of a first step and a subsequent second step. The first step has a pattern in which the heating temperature is increased under a reduced pressure atmosphere and a gas comprising at least an inert gas is supplied to the vacuum furnace under the reduced pressure atmosphere. The second step has a pattern in which the heating temperature is increased under a reduced pressure atmosphere in which a gas comprising a smaller amount of an inert gas than in the first step is supplied to the furnace or under a vacuum pressure atmosphere in which no gas is supplied to the furnace.
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公开(公告)号：HK51895A
公开(公告)日：1995-04-13
申请号：HK51895
申请日：1995-04-06
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： OHGA YUICHI , DANZUKA TOSHIO , KANAMORI HIROO , YOKOTA HIROSHI
IPC: C03B37/014 , C03B37/018
Abstract: A method for producing a porous preform for use in the fabrication of an optical fiber with at least two burners for synthesizing glass soot particles at least one of which generates a double-layer flame and at least one of which is used for forming a core part of the preform, which method comprises steps of supplying SiCl4 and optionally GeCl4 to an inner flame of the double-layer flame, and SiCl4 to an outer flame of the double-layer flame to flame hydrolyze the supplied compounds to synthesize glass soot particles, supplying SiCl4 and GeCl4 as glass-forming raw materials to the burner for forming the core part to flame hydrolyze the supplied compound to synthesized glass soot particles and depositing the generated glass soot particles on the lower end of a rotating starting member and growing the porous preform in a direction of an axis of the starting member to produce the porous preform comprising a core part containing at least partly GeO2, a porous preform produced by this method gives a transparent glass preform a surface of which is not cracked or peeled off.
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公开(公告)号：AU6477594A
公开(公告)日：1994-12-22
申请号：AU6477594
申请日：1994-06-17
Applicant: SUMITOMO ELECTRIC INDUSTRIES
Inventor： ITO MASUMI , HOSHINO SUMIO , DANZUKA TOSHIO
IPC: C03B37/014 , C03B37/018
Abstract: A method of manufacturing an optical fiber in which the deviation of a cutoff wavelength from a design value can be minimized. It is found that, upon diameter reduction of a porous core glass body by heat treatment, when the diameter reduction ratio is set to a value larger than 0.90, a "spike" in the refractive index distribution curve of a core can be prevented, and the deviation of the cutoff wavelength from the design value can be minimized. Therefore, there is provided a method comprising the first step of depositing fine SiO2 particles and fine GeO2 particles, which are produced by a core formation burner (31), to grow a porous core glass body (21) from a distal end of a rotating starting rod (16) in an axial direction, the second step of performing diameter reduction by heating the grown porous core glass body by heating means (33) while growing the porous core glass body, and the third step of depositing fine SiO2 particles produced by a cladding formation burner (32) to form a porous cladding glass layer on an outer surface of the diameter-reduced porous core glass body while performing growing and diameter reduction of the porous core glass body, wherein an outer diameter of the porous core glass body after the second step of performing diameter reduction is larger than 0.90 times an outer diameter before diameter reduction.
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