KR20010091370A - Method for fabricating an optical fiber preform - Google Patents

Method for fabricating an optical fiber preform Download PDF

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Publication number
KR20010091370A
KR20010091370A KR1020000012977A KR20000012977A KR20010091370A KR 20010091370 A KR20010091370 A KR 20010091370A KR 1020000012977 A KR1020000012977 A KR 1020000012977A KR 20000012977 A KR20000012977 A KR 20000012977A KR 20010091370 A KR20010091370 A KR 20010091370A
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South Korea
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base material
optical fiber
sleeve tube
secondary sleeve
manufacturing
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KR1020000012977A
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Korean (ko)
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KR100326323B1 (en
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서만석
오성국
이지훈
도문현
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윤종용
삼성전자 주식회사
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    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/01205—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments
    • C03B37/01225—Means for changing or stabilising the shape, e.g. diameter, of tubes or rods in general, e.g. collapsing
    • C03B37/0124—Means for reducing the diameter of rods or tubes by drawing, e.g. for preform draw-down
    • C03B37/01245—Means for reducing the diameter of rods or tubes by drawing, e.g. for preform draw-down by drawing and collapsing
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B37/00—Manufacture or treatment of flakes, fibres, or filaments from softened glass, minerals, or slags
    • C03B37/01—Manufacture of glass fibres or filaments
    • C03B37/012—Manufacture of preforms for drawing fibres or filaments
    • C03B37/014—Manufacture of preforms for drawing fibres or filaments made entirely or partially by chemical means, e.g. vapour phase deposition of bulk porous glass either by outside vapour deposition [OVD], or by outside vapour phase oxidation [OVPO] or by vapour axial deposition [VAD]

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacture, Treatment Of Glass Fibers (AREA)

Abstract

PURPOSE: A method for manufacturing a raw material of an optical fiber is provided to reduce a time for manufacturing an optical fiber by condensing and closing the first raw material and the second sleeve tube simultaneously. CONSTITUTION: The first raw material(11) and the second sleeve tube(12) are installed on a vertical lathe. The first raw material(11) and the second sleeve tube(12) are rotated to the same direction on the vertical lathe. The first raw material(11) is fixed to the first dummy tube(14a) and on an upper chuck of the vertical lathe. The second sleeve tube(12) is fixed to the second dummy tube(13a) and on a lower chuck of the vertical lathe. A gas supply tube is installed on an upper side of the vertical lathe. A vacuum pump(16) is installed on a lower side of the vertical lathe. A heating portion(20) is installed on an outer circumference of the second sleeve tube(12).

Description

광섬유 모재의 제조방법{METHOD FOR FABRICATING AN OPTICAL FIBER PREFORM}METHODS FOR FABRICATING AN OPTICAL FIBER PREFORM}

본 발명은 광통신 시스템에서 사용되는 광섬유의 모재 제조방법에 관한 것으로서, 특히 공정시간을 효율적으로 단축하여 생산성을 증대시킬 수 있는 광섬유 모재의 제조방법에 관한 것이다.The present invention relates to a method for manufacturing a base material of an optical fiber used in an optical communication system, and more particularly, to a method for manufacturing an optical fiber base material which can increase productivity by shortening process time efficiently.

통상적으로, 광 전송 시스템(Optical Transmission System) 굴절률이 다른 코어(Core)와 클래드(Clad)층으로 구성되는 글래스 재질의 광섬유(Optical Fiber)를 사용하고 있다. 또한, 점차 저손실 고강도의 광섬유를 생산하기 위하여 경주하고 있으며, 특히 상기 광섬유를 인출하기 위한 광섬유 모재(Optical Fiber Preform)를 제조하는 방법의 개발에 우선적인 역점을 두고 있는 실정이다.In general, an optical transmission system (Optical Transmission System) is used for the optical fiber made of a glass material composed of a core and a clad layer having different refractive index. In addition, the situation is gradually racing to produce a low-loss high-strength optical fiber, and in particular, the situation is primarily focused on the development of a method for manufacturing an optical fiber preform for drawing out the optical fiber.

상기 광섬유 모재를 제조하기 위한 방법으로는 주로 수정된 화학기상증착 즉, MCVD법(Modified Chemical Vapor Deposition)법을 사용하고 있으며, 이는 석영관(Quartz Reaction Tube)내에 화학조성물을 가스의 형태로 주입하고, 상기 석영관의 외부를 균일하게 가열하므로써, 내부에 일정 증착층이 생기도록 하여 제조하는 방법이다. 이를 증착(Deposition)공정이라 하며, 증착된 상기 석영관은 로드(Rod)형태의 모재봉으로 형성시키는 응축(Collapsing)공정과, 이를 마감하는 클로징(Closing)공정을 거치게 된다.As a method for manufacturing the optical fiber base material, modified chemical vapor deposition, that is, MCVD (Modified Chemical Vapor Deposition) method is used, which injects a chemical composition into a quartz tube in the form of a gas. By uniformly heating the outside of the quartz tube, a method is produced in which a predetermined deposition layer is formed inside. This is called a deposition process, and the deposited quartz tube undergoes a condensation process of forming a rod-like base rod and a closing process of finishing it.

상기 증착, 응축 및 클로징 공정은 소정의 선반(Lathe)상에 상기 석영관을 회전하도록 설치한후, 상기 석영관의 외주면상에 고온의 열을 가하므로써, 내부의 원료가스가 산화반응에 의해 상기 석영관의 내주면상에 증착되므로써 광섬유의 모재를 제조하는 전반적인 과정을 지칭한다.The deposition, condensation, and closing processes are installed to rotate the quartz tube on a predetermined lathe, and then the high temperature heat is applied to the outer circumferential surface of the quartz tube so that the raw material gas is oxidized by the oxidation reaction. It refers to the overall process of manufacturing the base material of the optical fiber by being deposited on the inner circumferential surface of the quartz tube.

근래들어, 상기 증착공정은 수평선반(Horizontal Lathe)을 이용하고 있는 추세이며, 증착공정에서 제조된 1차모재는 수직선반(Vertical Lathe)을 이용하여 응축공정 및 클로징 공정을 거쳐 광섬유 모재를 제조하게 된다.In recent years, the deposition process is using a horizontal lathe (Horizontal Lathe), the primary base material produced in the deposition process using a vertical lathe (Vertical Lathe) through the condensation process and closing process to produce the optical fiber base material do.

상기 응축 및 클로징 공정에서는 석영관의 연화점 이상의 고온으로 가열하기때문에 수평선반에서 이와 같은 공정을 하게되면 온도구배가 발생하게 된다. 이 온도구배는 상기 석영관의 점성도 차이를 유발하고 또한 비원율(Tube Ovality)을 증가시키게 된다. 그 결과, 응축공정이 진행됨에 따라 비원율은 증가하게 되고 이는 편광모드분산(PMD; Polarization Mode Dispersion)을 증가시키는 결과를 가져오게 된다. 따라서, 상기 수평선반보다는 수직선반을 선호하게 된다.In the condensation and closing process, the heating is performed at a high temperature above the softening point of the quartz tube. This temperature gradient causes a difference in the viscosity of the quartz tube and also increases the Tube Ovality. As a result, as the condensation process proceeds, the specific ratio increases, resulting in an increase in polarization mode dispersion (PMD). Therefore, the vertical shelf is preferred to the horizontal shelf.

한편, 상기 수직선반상에서 상기 광섬유 모재봉상에 2차 슬리브 튜브를 사용하여 오버자켓팅을 하게 된다. 상기 오버자켓팅을 하여 대구경의 모재를 제조하게 되면, 광섬유를 인출하기 위한 장조장을 실현할 수 있는 장점이 있다.On the other hand, on the vertical shelf is over-jacketed by using a secondary sleeve tube on the optical fiber base rod. When manufacturing the large-diameter base material by the over-jacketing, there is an advantage that can realize the length of the market for drawing the optical fiber.

그러나 상기와 같이, 증착, 응축 및 클로징공정까지 마친 광섬유 모재상에 오버자켓팅을 하게되면, 광섬유 모재를 제조하는 제조시간이 길어지는 문제점이 발생하게 된다.However, as described above, if the over-jacketing on the optical fiber base material is completed until the deposition, condensation and closing process, the manufacturing time for manufacturing the optical fiber base material is prolonged.

상기와 같은 문제점을 해결하기 위하여 본 발명의 목적은 오버자켓팅시, 광섬유 제조시간을 단축할 수 있는 광섬유 모재의 제조방법을 제공하는데 있다.In order to solve the above problems, an object of the present invention is to provide a method for manufacturing an optical fiber base material that can shorten the optical fiber manufacturing time when overjacking.

본 발명의 다른 목적은 1차 모재의 응축 및 클로징 공정시, 모재의 외경 변형, Ge 침투를 미연에 방지할 수 있는 광섬유 모재의 제조방법을 제공하는데 있다.Another object of the present invention is to provide a method for manufacturing an optical fiber base material which can prevent the outer diameter deformation of the base material and the penetration of Ge in the condensation and closing process of the primary base material.

본 발명의 또 다른 목적은 광섬유 모재의 점성도 및 1차 모재의 코어 비원율에 대한 안정성을 확보할 수 있도록 구성되는 광섬유 모재의 제조방법을 제공하는데 있다.Still another object of the present invention is to provide a method for manufacturing an optical fiber base material, which is configured to ensure stability of the viscosity of the optical fiber base material and the core specific ratio of the primary base material.

상기와 같은 목적을 달성하기 위하여 본 발명은 수직선반에 의해서 2차 슬리브 튜브로 오버자켓팅 공정을 통해 광섬유 모재를 제조하는 방법에 있어서, 상기 2차 슬리브 튜브내에 증착공정이 완료된 1차 모재를 삽입후, 상기 2차 슬리브의 외주면상에 가열수단에 의해 고온의 열을 가하여 상기 1차 모재와 2차 슬리브 튜브를 동시에 응축 및 클로징시킴을 특징으로 한다.In order to achieve the above object, the present invention provides a method for manufacturing an optical fiber base material through the over-jacketing process to the secondary sleeve tube by a vertical shelf, inserting the primary base material completed the deposition process in the secondary sleeve tube Then, by applying a high temperature heat on the outer circumferential surface of the secondary sleeve by the heating means to condense and close the primary base material and the secondary sleeve tube at the same time.

도 1은 본 발명의 바람직한 일실시예에 따른 광섬유 모재의 제조장치를 도시한 구성도.1 is a block diagram showing an apparatus for manufacturing an optical fiber base material according to an embodiment of the present invention.

도 2는 본 발명의 바람직한 일실시예에 따른 2차 슬리브 튜브내에 1차 모재가 삽입된 상태를 도시한 부분단면도.Figure 2 is a partial cross-sectional view showing a state in which the primary base material is inserted into the secondary sleeve tube according to an embodiment of the present invention.

<도면의 주요 부호에 대한 설명><Description of Major Symbols in Drawing>

10: 수직선반 11: 1차 모재10: vertical lathe 11: primary substrate

12: 2차 슬리브 튜브 15: 가스공급관12: secondary sleeve tube 15: gas supply pipe

16: 진공펌프16: vacuum pump

이하 본 발명의 바람직한 실시예를 첨부된 도면을 참조하여 상세히 설명하면 다음과 같다. 그리고, 본 발명의 요지를 불필요하게 흐릴 수 있다고 판단되는 경우 그 상세한 설명을 생략한다.Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the case where it is determined that the gist of the present invention may be unnecessarily obscured, detailed description thereof will be omitted.

오버자켓팅 공정으로 광섬유 모재를 제조하기 위한 본 발명은 증착공정을 완료한 1차 모재(Semi-Preform)와 2차 슬리브 튜브에 동시에 응축(Collapsing)공정 및 클로징(Closing)공정을 수행시키므로써, 기존의 증착, 응축 및 클로징공정을 거친 광섬유 모재를 2차 슬리브 튜브에 삽입한 후, 다시 응축 및 클로징 공정을 거치는 과정보다 제조 공정 시간이 현저히 단축된다.The present invention for manufacturing the optical fiber base material by the over jacketing process by simultaneously performing the condensation (Collapsing) process and closing (Closing process) to the primary substrate (Semi-Preform) and the secondary sleeve tube completed the deposition process, The manufacturing process time is significantly shorter than the process of inserting an optical fiber base material, which has undergone conventional deposition, condensation, and closing processes, into a secondary sleeve tube and then undergoing condensation and closing processes again.

도 1은 본 발명의 바람직한 일실시예에 따른 광섬유 모재의 제조장치를 도시한 구성도이고, 도 2는 2차 슬리브 튜브내에 1차 모재가 삽입된 상태를 도시한 부분단면도이다.1 is a block diagram showing an apparatus for manufacturing an optical fiber base material according to an embodiment of the present invention, Figure 2 is a partial cross-sectional view showing a state in which the primary base material is inserted into the secondary sleeve tube.

본 발명에 의하여 광섬유 모재를 제조하기 위한 오버자켓팅 공정은 수직선반상에서 수행된다. 도 1 및 도 2에 도시한 바와 같이, 수직선반(10)상에 1차모재(11) 및 2차 슬리브 튜브(12)를 회전 가능하도록 설치한다. 이때, 상기 1차 모재(11)와 2차 슬리브 튜브(12)를 같은 방향으로 함께 같은 속도로 회전되도록 설치한다. 따라서, 상기 1차 모재(11)는 1차 더미튜브(14a)에 고정되어 상기 수직선반(10)의 상부척(14)상에 고정되며, 상기 2차 슬리브 튜브(12)는 2차 더미 튜브(13a)에 고정되어 상기 수직선반(10)의 하부척(13)상에 고정된다.The overjacketing process for manufacturing the optical fiber base material by the present invention is carried out on a vertical shelf. 1 and 2, the primary base material 11 and the secondary sleeve tube 12 are installed on the vertical shelf 10 so as to be rotatable. At this time, the primary base material 11 and the secondary sleeve tube 12 are installed to rotate at the same speed together in the same direction. Accordingly, the primary base material 11 is fixed to the primary dummy tube 14a and fixed on the upper chuck 14 of the vertical shelf 10, and the secondary sleeve tube 12 is the secondary dummy tube. It is fixed to 13a, and is fixed on the lower chuck 13 of the vertical shelf 10.

상기 수직선반(10)의 상측상에는 응축 공정시, 상기 1차 모재(11) 및 2차 슬리브 튜브(12)내의 수분 및 OH기를 제거하고 가스유입량을 조절하기 위하여 N2, Cl2, O2등의 가스를 흘려주기 위한 가스 공급관(15)이 설치된다.On the upper side of the vertical shelf 10, in the condensation process, N 2 , Cl 2 , O 2, etc., in order to remove water and OH groups in the primary base material 11 and the secondary sleeve tube 12 and to control the gas flow rate. The gas supply pipe 15 for flowing the gas of gas is provided.

또한, 상기 수직선반(10)의 하측상에는 클로즈 공정시, 상기 1차 모재(11) 및 2차 슬리브 튜브(12)내에 음압(Negative Pressure)을 형성시켜 주므로써, 모재의 제조시간을 단축할 수 있을뿐 아니라 상기 가스 공급관(15)에서 공급되었던 폐가스를 배출시킬 수 있는 진공펌프(Vacuum Pump)(16)가 설치된다.In addition, by forming a negative pressure on the lower side of the vertical shelf 10 in the primary base material 11 and the secondary sleeve tube 12 during the closing process, the manufacturing time of the base material can be shortened. In addition, a vacuum pump 16 capable of discharging the waste gas supplied from the gas supply pipe 15 is installed.

그후, 상기 2차 슬리브 튜브(12)의 외주면상에는 응축 및 클로징 공정시 고온의 열을 가하기 위한 가열수단(20)이 상하 수직으로 왕복운동을 할 수 있도록 설치된다.Then, on the outer circumferential surface of the secondary sleeve tube 12, a heating means 20 for applying high temperature heat during the condensation and closing process is installed to reciprocate vertically up and down.

상기와 같이 구성된 수직선반(10)상에서 오버자켓팅 방법으로 광섬유 모재를 제조하기 위한 과정은 우선 수직선반상에 1차 모재(11)가 삽입된 2차 슬리브 튜브(12)를 회전가능하도록 설치한다. 이때, 상기 1차 모재(11)와 2차 슬리브 튜브(12)는 함께 회전되도록 고정된다.The process for manufacturing the optical fiber base material by the over jacketing method on the vertical shelf 10 configured as described above first installs the secondary sleeve tube 12 in which the primary base material 11 is inserted on the vertical shelf. At this time, the primary base material 11 and the secondary sleeve tube 12 are fixed to rotate together.

그후, 상기 2차 슬리브 튜브(12)의 외주면상에 가열수단(20)에 의해 고온의 열을 가한다. 이때, 가열수단(20)은 수직방향으로 왕복운동을 할 수 있도록 설치된다. 이때, 가스 공급관(15)에서는 1차 모재(11) 및 2차 슬리브 튜브(12)내의 수분 제거 및 OH기의 제거를 위하여 N2, Cl2, O2등의 가스를 흘려주게 된다. 상기 가열수단(20)이 상기 2차 슬리브 튜브(12)를 가열하는 가열온도는 적어도 2200도 이상으로 한다.Thereafter, high temperature heat is applied by the heating means 20 on the outer circumferential surface of the secondary sleeve tube 12. At this time, the heating means 20 is installed to reciprocate in the vertical direction. At this time, the gas supply pipe 15 flows a gas such as N 2 , Cl 2 , O 2 to remove moisture in the primary base material 11 and the secondary sleeve tube 12 and to remove the OH group. The heating temperature at which the heating means 20 heats the secondary sleeve tube 12 is at least 2200 degrees or more.

그후, 상기 2차 슬리브 튜브(12) 및 1차 모재(11)는 연화점 이상으로 가열되어 응축공정을 거친후 클로징공정을 거치게 된다. 상기 클로징 공정시에는 진공펌프(16)를 동작시키게 되므로 상측에서 하측으로 유동하는 가열수단(20)에 의해 클로징속도가 증가된다. 즉, 진공 응축 공정에 의한 클로징 속도가 증가되는 것이다.Thereafter, the secondary sleeve tube 12 and the primary base material 11 are heated to a softening point or more, undergo a condensation process, and then undergo a closing process. Since the vacuum pump 16 is operated during the closing process, the closing speed is increased by the heating means 20 flowing from the upper side to the lower side. That is, the closing speed by the vacuum condensation process is increased.

상술한 바와 같이 본 발명의 실시예에 따른 광섬유 모재의 제조방법은 1차 모재와 2차 슬리브 튜브의 응축 및 클로징 공정을 동시에 수행하므로써 모재 제조 시간이 단축되며, 1차 모재에 직접적인 열응력이 가해지지 않기때문에 외경 변형에 의한 코어의 비원율 및 점성도에 대한 안정성이 확보되는 효과가 있다.As described above, the method of manufacturing the optical fiber base material according to the embodiment of the present invention shortens the base material manufacturing time by simultaneously performing the condensation and closing processes of the primary base material and the secondary sleeve tube, and direct thermal stress is applied to the primary base material. Since it is not supported, there is an effect of securing stability against specific gravity and viscosity of the core due to the outer diameter deformation.

Claims (3)

수직선반에 의해서 2차 슬리브 튜브로 오버자켓팅 공정을 통해 광섬유 모재를 제조하는 방법에 있어서,In the method of manufacturing the optical fiber base material through the over jacketing process to the secondary sleeve tube by a vertical shelf, 상기 2차 슬리브 튜브내에 증착공정이 완료된 1차 모재를 삽입후, 상기 2차 슬리브의 외주면상에 가열수단에 의해 고온의 열을 가하여 상기 1차 모재와 2차 슬리브 튜브를 동시에 응축 및 클로징시킴을 특징으로 하는 광섬유 모재의 제조방법.After inserting the primary base material having completed the deposition process in the secondary sleeve tube, by applying a high temperature heat by the heating means on the outer peripheral surface of the secondary sleeve to condense and close the primary base material and the secondary sleeve tube at the same time. Method for producing an optical fiber base material characterized in that. 제 1 항에 있어서,The method of claim 1, 상기 응축 및 클로징과정을 원활히 수행하기 위하여, 상기 2차 슬리브 튜브의 하측상에 진공펌프를 설치하여 상기 1차 모재와 2차 슬리브 튜브내에 음압을 형성함을 특징으로 하는 광섬유 모재의 제조방법.In order to smoothly perform the condensation and closing process, a vacuum pump is installed on the lower side of the secondary sleeve tube to form a negative pressure in the primary base material and the secondary sleeve tube, characterized in that the manufacturing method of the optical fiber base material. 제 1 항에 있어서,The method of claim 1, 상기 가열수단에 의해 가열되는 온도는 적어도 2200도 이상임을 특징으로 하는 광섬유 모재의 제조방법.And a temperature heated by the heating means is at least 2200 degrees or more.
KR1020000012977A 2000-03-15 2000-03-15 Method for fabricating an optical fiber preform KR100326323B1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100539869B1 (en) * 2002-08-29 2005-12-28 삼성전자주식회사 Apparatus of sintering for gel tube and fabrication method of large aperture optical fiber preform using thereof
KR100556316B1 (en) * 2002-09-12 2006-03-03 엘에스전선 주식회사 Method of RIT process for removing water in the gap of rod and tube

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KR20040001169A (en) * 2002-06-27 2004-01-07 삼성전자주식회사 Over jacketing equipment for optical fiber preform

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100539869B1 (en) * 2002-08-29 2005-12-28 삼성전자주식회사 Apparatus of sintering for gel tube and fabrication method of large aperture optical fiber preform using thereof
KR100556316B1 (en) * 2002-09-12 2006-03-03 엘에스전선 주식회사 Method of RIT process for removing water in the gap of rod and tube

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