KR100398070B1 - Water bocking method in the interfacing surface during the joining of core and clad - Google Patents

Water bocking method in the interfacing surface during the joining of core and clad Download PDF

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KR100398070B1
KR100398070B1 KR10-2001-0067239A KR20010067239A KR100398070B1 KR 100398070 B1 KR100398070 B1 KR 100398070B1 KR 20010067239 A KR20010067239 A KR 20010067239A KR 100398070 B1 KR100398070 B1 KR 100398070B1
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tube
clad
wedge
core preform
handle
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KR10-2001-0067239A
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Korean (ko)
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KR20030035256A (en
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권영일
배상준
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엘지전선 주식회사
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    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/02—Optical fibres with cladding with or without a coating
    • 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]
    • C03B37/01413—Reactant delivery systems
    • C03B37/0142—Reactant deposition burners

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

Abstract

본 발명은 광섬유 제조공정에 있어서 1차 코어프리폼에 클래드 튜브를 화염으로 접합시키는 공정에 있어, 화염으로부터 발생되는 수분이 1차코어프리폼과 클래드 튜브사이의 경계면에 침투하는 것을 방지하기 위한 코어프리폼과 클래드 튜브 접합시 경계면에서의 수분침투 방지방법에 관한 것으로, 광섬유 제조 공정중 일측단에 핸들튜브(6)가 접합된 클래드 튜브(2)와 상기 클래드튜브(2)를 1차 제조된 코어 프리폼(4)에 접합시키는 방법에 있어서, 쐐기형 튜브(7)를 상기 핸들튜브(6)의 타단측에 미리 접합시키는 단계와; 상기 핸들튜브(6)와 상기 클래드튜브(2) 및 상기 쐐기형 튜브(7)를 세척한 후 완전 건조시켜 상기 클래드튜브(2), 쐐기형 튜브(7), 핸들튜브(6)의 내부측 수분을 제거하는 단계와; 상기 클래드튜브(2)내에 진공력을 가함과 동시에 핸들튜브(6)를 회전시키면서 상기 쐐기형 튜브(7)를 가스버너로 가열하여 코어프리폼(4)에 접합시키는 단계를 포함한 것을 특징으로 한다.The present invention provides a process for bonding a clad tube to a primary core preform with a flame in an optical fiber manufacturing process, the core preform for preventing the moisture generated from the flame from penetrating the interface between the primary core preform and the clad tube. The present invention relates to a method for preventing moisture penetration at an interface when cladding a clad tube, and includes a clad tube (2) having a handle tube (6) bonded to one end of an optical fiber manufacturing process and a core preform (1) manufactured by the clad tube (2). 4) A method of joining to (4), comprising: joining a wedge-shaped tube (7) to the other end side of the handle tube (6) in advance; The handle tube (6), the clad tube (2) and the wedge tube (7) is washed and completely dried to the inner side of the clad tube (2), wedge tube (7), handle tube (6) Removing moisture; It is characterized in that it comprises the step of heating the wedge-shaped tube (7) with a gas burner and bonding it to the core preform (4) while applying a vacuum force to the clad tube (2) and simultaneously rotating the handle tube (6).

Description

코어프리폼과 클래드 튜브 접합시 경계면에서의 수분침투 방지방법{Water bocking method in the interfacing surface during the joining of core and clad}Water bocking method in the interfacing surface during the joining of core and clad}

본 발명은 광섬유 제조공정에 있어서 1차 코어프리폼에 클래드 튜브를 화염으로 접합시키는 공정에 있어, 화염으로부터 발생되는 수분이 1차코어프리폼과 클래드 튜브사이의 경계면에 침투하는 것을 방지하기 위한 코어프리폼과 클래드 튜브 접합시 경계면에서의 수분침투 방지방법에 관한 것이다.The present invention provides a process for bonding a clad tube to a primary core preform with a flame in an optical fiber manufacturing process, the core preform for preventing the moisture generated from the flame from penetrating the interface between the primary core preform and the clad tube. The present invention relates to a method for preventing water penetration at the interface when cladding a clad tube.

광섬유 구조는 내층에 외층보다 상대적으로 큰 굴절율을 가지는 코어와 그 외부에 클래드(clad)로 구성되어 있으며, 현재까지 알려진 광섬유 제조방법은 MCVD(Modified Chemical Vapor Deposition), VAD(Vapor Axial Deposition), OVD (Outside Vapor Deposition) 등이 있다.The optical fiber structure is composed of a core having a relatively higher refractive index than the outer layer and a clad on the outside thereof. The optical fiber manufacturing methods known to date are MCVD (Modified Chemical Vapor Deposition), VAD (Vapor Axial Deposition), and OVD. (Outside Vapor Deposition).

본 발명은 MCVD 방법으로 광섬유를 제조할 때, MCVD 방법으로 1차 코어프리폼(core preform)을 제조하고, 이 코어 프리폼을 대형 클래드 튜브 속에 수직으로 삽입한 후 가스버너를 사용 접합하여 광섬유 프리폼을 제조하는 RIT(Rod in Tube)공정에 있어서 열원으로 사용하는 산소/수소 버너의 연소 시 발생되는 수분이 코어와 클래드 경계면에 침투하는 것을 최소화함으로서 잔류 수분이 코어와 클래드 경계면에 침투하는 것을 최소화함으로서 잔류 수분에 따른 광섬유에 요구되는 주요 특성 중 하나인 산화수소이온(OH-) 손실 증가를 방지하고 접합 생산성을 향상시키기 위한 것이다.When the optical fiber is manufactured by the MCVD method, the first core preform is manufactured by the MCVD method, the core preform is vertically inserted into a large clad tube, and then bonded using a gas burner to prepare the optical fiber preform. In the RIT (Rod in Tube) process, the moisture generated during the combustion of the oxygen / hydrogen burner used as a heat source is minimized to penetrate the core and clad interface, thereby minimizing the infiltration of residual moisture into the core and clad interface. This is to prevent the increase of hydrogen oxide ion (OH-) loss, which is one of the main characteristics required for the optical fiber, and to improve the bonding productivity.

도 1은 종래 1차 코어 프리폼을 클래드 튜브와 접합시키는 장치의 개략도이고, 도 2는 종래 1차 코어 프리폼을 얇은 일자형 튜브가 설치된 클래드 튜브와 접합시키는 장치의 개략도이다.1 is a schematic diagram of an apparatus for bonding a conventional primary core preform with a clad tube, and FIG. 2 is a schematic diagram of an apparatus for bonding a conventional primary core preform with a clad tube provided with a thin straight tube.

종래는 도 1과 같이, 진공원(1)측에서 진공력을 방생시키면서 핸들튜브(6)가 접합된 대형 클래드튜브(2)외부를 직접 가스버너(3)의 고열로 가열하여 코어프리폼 (4)과 접합시키거나, 도 2와 같이 클래드 튜브(2)의 끝단에 얇은 일자형 튜브(5)를 설치하여 가스버너(3)로 접합시키는 방법을 사용하였다.Conventionally, as shown in FIG. 1, the core preform is formed by directly heating the outside of the large clad tube 2 to which the handle tube 6 is bonded while generating a vacuum force on the vacuum source 1 side by a high temperature of the gas burner 3. ), Or a thin straight tube 5 is installed at the end of the clad tube 2 to join the gas burner 3 as shown in FIG. 2.

이럴 경우 가스버너(3)의 열원에서 발생하는 높은 산소/소소 분출속도 및 그 압력에 의해 연소시 생기는 수분이 다량 그 경계면에 침투함으로서 접합 후 잔존하는 수분에 따른 산화수소이온의 손실 증가 문제가 있어 왔다.In this case, the high oxygen / sodium ejection rate generated from the heat source of the gas burner 3 and the moisture generated during combustion penetrate the interface so that there is a problem of increasing the loss of hydrogen ions due to the moisture remaining after the bonding. come.

즉, 경계면에 침투된 수분은 응축되어 코어 프리홈 경계면에 물자국을 형성시키며, 하부에서 발생되는 진공력에 의해 일부 제거되기도 하지만 이 과정에서 잔류되는 수분은 RIT공정의 후공정인 인선과정에서의 높은 열(약2000℃ 이상)에 의해 산화수소이온을 형성시키고 고온의 열로 인하여 코어 프리홈 속으로 확산되어 지므로 OH-손실 증가를 일으킨다.In other words, the water penetrated into the interface is condensed to form a material station at the core free groove interface, and partly removed by the vacuum force generated from the lower part, but the remaining water in this process is removed during the cutting process, which is a post process of the RIT process. Hydrogen ions are formed by high heat (approximately 2000 ° C or higher) and diffuse into the core pregrooves due to high heat, resulting in increased OH loss.

본 발명은 상기와 같은 종래 기술의 문제점을 해결하기 위한 것으로, 1차 코어 프리폼과 클래드 튜브를 접합시 접합 경계면에서 침투하는 수분의 량을 최소화하고 빠른 시간에 초기 접합이 가능토록 한 코어프리폼과 클래드 튜브 접합시 경계면에서의 수분침투 방지방법을 제공함에 그 목적이 있다.The present invention is to solve the problems of the prior art as described above, the core preform and clad to minimize the amount of water penetrates at the bonding interface when the primary core preform and the cladding tube, and to enable early bonding in a short time It is an object of the present invention to provide a method for preventing water penetration at the interface when joining tubes.

상기의 목적을 달성하기 위한 본 발명의 구체적인 수단은,Specific means of the present invention for achieving the above object,

광섬유 제조 공정중 일측단에 핸들튜브(6)가 접합된 클래드 튜브(2)와 상기 클래드튜브(2)를 1차 제조된 코어 프리폼(4)에 접합시키는 방법에 있어서,In the method for bonding the clad tube (2) and the clad tube (2) to the core preform (4) manufactured in the first stage during the optical fiber manufacturing process,

쐐기형 튜브(7)를 상기 핸들튜브(6)의 타단측에 미리 접합시키는 단계와;Bonding the wedge-shaped tube (7) to the other end side of the handle tube (6) in advance;

상기 핸들튜브(6)와 상기 클래드튜브(2) 및 상기 쐐기형 튜브(7)를 세척한 후 완전 건조시켜 상기 클래드튜브(2), 쐐기형 튜브(7), 핸들튜브(6)의 내부측 수분을 제거하는 단계와;The handle tube (6), the clad tube (2) and the wedge tube (7) is washed and completely dried to the inner side of the clad tube (2), wedge tube (7), handle tube (6) Removing moisture;

상기 클래드튜브(2)내에 진공력을 가함과 동시에 핸들튜브(6)를 회전시키면서 상기 쐐기형 튜브(7)를 가스버너로 가열하여 코어프리폼(4)에 접합시키는 단계를 포함한 것을 특징으로 한다.It is characterized in that it comprises the step of heating the wedge-shaped tube (7) with a gas burner and bonding it to the core preform (4) while applying a vacuum force to the clad tube (2) and simultaneously rotating the handle tube (6).

도 1은 종래 1차 코어 프리폼을 클래드 튜브와 접합시키는 장치의 개략도.1 is a schematic representation of an apparatus for bonding a conventional primary core preform with a clad tube.

도 2는 종래 1차 코어 프리폼을 얇은 일자형 튜브가 설치된 클래드 튜브와 접합시키는 장치의 개략도.2 is a schematic diagram of a device for joining a conventional primary core preform with a cladding tube equipped with a thin straight tube.

도 3은 본 발명의 실시예에 따른 클래드 튜브에 핸들튜브와 쐐기형튜브가 미리 접합된 단면도.Figure 3 is a cross-sectional view of the handle tube and the wedge tube is bonded in advance to the cladding tube according to an embodiment of the present invention.

도 4는 본 발명의 실시예에 따른 클래드 튜브내에 1차 코어프리폼이 위치된 상태에서 쐐기형튜브를 접합시키기 위한 제작 공정도.Figure 4 is a manufacturing process for joining the wedge-shaped tube in the state where the primary core preform is located in the clad tube according to an embodiment of the present invention.

<도면의 주요 부분에 대한 부호의 설명><Explanation of symbols for the main parts of the drawings>

2 : 클래드 튜브 3 : 가스버너2: clad tube 3: gas burner

4 : 1차 코어프리폼 6 : 핸들 튜브4: 1st core preform 6: handle tube

7 : 쐐기형 튜브7: wedge tube

이하, 첨부된 도면을 참조하여 본 발명의 바람직한 실시예를 상세히 설명한다.Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

도 3은 본 발명에 따른 클래드 튜브(2)에 핸들튜브(6)와 쐐기형튜브(7)가 미리 접합된 단면도를 나타내고 있다.3 shows a cross-sectional view in which the handle tube 6 and the wedge-shaped tube 7 are previously bonded to the clad tube 2 according to the present invention.

본 발명은 도 3과 같이 일단측에 핸들튜브(6)가 접합된 상기 핸들튜브(6)의 타단측에 쐐기형 튜브(7)를 미리 접합시키는 쐐기형 튜브 접합공정으로 개시된다.The present invention is disclosed in the wedge-shaped tube joining process for joining the wedge-shaped tube (7) in advance to the other end side of the handle tube 6, the handle tube 6 is bonded to one end side as shown in FIG.

이때 사용되는 쐐기형 튜브(7)는 도 4와 같이 가스버너(3)의 열원에 쉽게 1차 코어 프리폼(4)에 열융착되어 접합될 수 있는 얇은 두께를 갖는다.At this time, the wedge-shaped tube 7 used has a thin thickness that can be easily heat-bonded to the primary core preform 4 to the heat source of the gas burner 3 as shown in FIG. 4.

도 3과 같이 클래드튜브(2)의 양단에 상기 핸들튜브(6)와 상기 쐐기형 튜브 (7)가 접합된 후에는 세척과 건조 과정을 순차적으로 거친다. 건조 단계가 끝나면 상기 클래드튜브(2), 쐐기형 튜브(7), 핸들튜브(6)의 내부측 수분은 완전 제거된다.After the handle tube 6 and the wedge-shaped tube 7 are joined to both ends of the clad tube 2 as shown in FIG. 3, the washing and drying processes are sequentially performed. At the end of the drying step, the internal moisture of the clad tube 2, the wedge tube 7 and the handle tube 6 is completely removed.

다음, 상기 클래드튜브(2)내에 진공력을 가함과 동시에 핸들튜브(6)를 회전시키면서 상기 쐐기형 튜브(7)를 가스버너(3)로 가열하여 코어프리폼(4)에 접합시킨다.Next, the wedge-shaped tube 7 is heated by the gas burner 3 and bonded to the core preform 4 while applying the vacuum force to the clad tube 2 and simultaneously rotating the handle tube 6.

이때 가스버너(3)에서 공급되는 화염은 쐐기형 튜브(7)의 기울기면에 의해 쐐기형 튜브(7)에 부딪친 후 클래드튜브(2)의 상측으로 유도된다.At this time, the flame supplied from the gas burner 3 is directed to the upper side of the clad tube 2 after hitting the wedge tube 7 by the inclined surface of the wedge tube 7.

이런 과정에서 쐐기형 튜브(2)의 상측단은 1차 코어프리폼(4)에 최소의 간격으로 배치됨으로서 가스버너(3)로 쐐기형 튜브(7)를 1차 코어프리폼(4)에 단시간에 접합시킬 수 있고, 접합 중에 쐐기형 튜브(7)와 클래드 튜브(7) 사이로의 수분 침투를 방지할 수 있다.In this process, the upper end of the wedge-shaped tube 2 is disposed in the primary core preform 4 with minimum spacing so that the wedge-shaped tube 7 is connected to the primary core preform 4 with the gas burner 3 in a short time. It is possible to bond and prevent water penetration between the wedge shaped tube 7 and the cladding tube 7 during joining.

상술한 바와 같이 본 발명의 코어프리폼과 클래드 튜브 접합시 경계면에서의 수분침투 방지방법에 따르면, 산소/수소를 열원으로 하여 가스버너를 사용 접합하는 환경하에서 미리 클래드 튜브에 쐐기형 튜브를 접합시킴과 동시에 화염을 쐐기형 튜브와 클래드튜브 사이의 틈새 바깥측으로 유도하여 1차 코어프리폼과 클래드튜브의 경계면에 수분 침투를 방지할 수 있고, 결국 광섬유에 요구되는 주요 특성 중의 하나인 OH- 손실 증가를 방지할 수 있다.As described above, according to the method for preventing water penetration at the interface when joining the core preform and the clad tube of the present invention, the wedge-shaped tube is bonded to the clad tube in advance in an environment where gas / burner is used with oxygen / hydrogen as the heat source. At the same time, flames can be directed outside the gap between the wedge tube and the clad tube to prevent moisture infiltration into the interface between the primary core preform and the clad tube, which in turn prevents the increase in OH loss, one of the main characteristics required for optical fibers. can do.

Claims (1)

광섬유 제조 공정중 일측단에 핸들튜브(6)가 접합된 클래드 튜브(2)와 상기 클래드튜브(2)를 1차 제조된 코어 프리폼(4)에 접합시키는 방법에 있어서,In the method for bonding the clad tube (2) and the clad tube (2) to the core preform (4) manufactured in the first stage during the optical fiber manufacturing process, 쐐기형 튜브(7)를 상기 핸들튜브(6)의 타단측에 미리 접합시키는 단계와;Bonding the wedge-shaped tube (7) to the other end side of the handle tube (6) in advance; 상기 핸들튜브(6)와 상기 클래드튜브(2) 및 상기 쐐기형 튜브(7)를 세척한 후 완전 건조시켜 상기 클래드튜브(2), 쐐기형 튜브(7), 핸들튜브(6)의 내부측 수분을 제거하는 단계와;The handle tube (6), the clad tube (2) and the wedge tube (7) is washed and completely dried to the inner side of the clad tube (2), wedge tube (7), handle tube (6) Removing moisture; 상기 클래드튜브(2)내에 진공력을 가함과 동시에 핸들튜브(6)를 회전시키면서 상기 쐐기형 튜브(7)를 가스버너로 가열하여 코어프리폼(4)에 접합시키는 단계를 포함한 것을 특징으로 하는 광섬유 제조시의 1차 코어프리폼과 클래드 튜브의 접합방법.And applying the vacuum force to the clad tube (2) and simultaneously rotating the handle tube (6) to heat the wedge-shaped tube (7) with a gas burner to bond it to the core preform (4). Joining method of primary core preform and clad tube at the time of manufacture.
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KR100496448B1 (en) * 2002-06-15 2005-06-20 엘에스전선 주식회사 method of prevention of water generation in the jacketing tube during RIT and apparatus thereof
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KR19980066124A (en) * 1997-01-20 1998-10-15 김광호 Fiber Optic Substrate Manufacturing Method
US5944865A (en) * 1996-04-25 1999-08-31 Samsung Electronics Co., Ltd. Apparatus for fabricating an optical fiber coated with metal and method therefor
JP2000169175A (en) * 1998-12-11 2000-06-20 Sumitomo Electric Ind Ltd Production of glass preform

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5944865A (en) * 1996-04-25 1999-08-31 Samsung Electronics Co., Ltd. Apparatus for fabricating an optical fiber coated with metal and method therefor
KR19980066124A (en) * 1997-01-20 1998-10-15 김광호 Fiber Optic Substrate Manufacturing Method
JP2000169175A (en) * 1998-12-11 2000-06-20 Sumitomo Electric Ind Ltd Production of glass preform

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