US20080047303A1 - Indirect heat type double-clad crystal fiber fabrication method - Google Patents
Indirect heat type double-clad crystal fiber fabrication method Download PDFInfo
- Publication number
- US20080047303A1 US20080047303A1 US11/590,778 US59077806A US2008047303A1 US 20080047303 A1 US20080047303 A1 US 20080047303A1 US 59077806 A US59077806 A US 59077806A US 2008047303 A1 US2008047303 A1 US 2008047303A1
- Authority
- US
- United States
- Prior art keywords
- double
- crystal
- crystal fiber
- optical fiber
- silica capillary
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000013078 crystal Substances 0.000 title claims abstract description 50
- 239000000835 fiber Substances 0.000 title claims abstract description 39
- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 51
- 229910052594 sapphire Inorganic materials 0.000 claims abstract description 28
- 239000010980 sapphire Substances 0.000 claims abstract description 28
- 239000013307 optical fiber Substances 0.000 claims abstract description 23
- 239000000377 silicon dioxide Substances 0.000 claims abstract description 23
- 230000005855 radiation Effects 0.000 claims abstract description 7
- 239000005350 fused silica glass Substances 0.000 claims abstract description 5
- 238000010438 heat treatment Methods 0.000 claims description 13
- 239000011521 glass Substances 0.000 claims description 6
- 239000003365 glass fiber Substances 0.000 description 5
- 238000003780 insertion Methods 0.000 description 4
- 230000037431 insertion Effects 0.000 description 4
- 230000005540 biological transmission Effects 0.000 description 3
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 230000002269 spontaneous effect Effects 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Images
Classifications
-
- 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
- C03B37/02—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor
- C03B37/025—Manufacture of glass fibres or filaments by drawing or extruding, e.g. direct drawing of molten glass from nozzles; Cooling fins therefor from reheated softened tubes, rods, fibres or filaments, e.g. drawing fibres from preforms
Definitions
- the present invention has been accomplished under the circumstances in view. It is one object of the present invention to provide an indirect heat type double-clad optical fiber fabrication method, which is practical to fabricate a double-clad optical fiber having a uniform diameter and a core diameter smaller than 10 microns.
- the double-clad optical fiber fabrication method double-clad optical fiber fabrication method is as follows: preparing a crystal fiber, and then inserting the crystal fiber into a silica capillary, and then attaching a sapphire tube to the periphery of the silica capillary, and then applying a laser beam to the sapphire tube to increase the temperature of the sapphire tube and to further fuse the silica capillary with thermal radiation to have the fused silica capillary be wrapped about the crystal fiber, thereby forming the desired double-clad optical fiber.
- FIG. 1 is a schematic drawing, showing a Cr:YAG crystal fiber with a silica capillary inserted in a sapphire tube and a laser beam applied to the sapphire tube for the growth of a double-clad optical fiber according to the present invention.
- FIG. 2 is a 2D temperature distribution chart obtained by means of insertion of a silica capillary and a Cr:YAG crystal fiber in a sapphire tube and heating of the sapphire tube with laser subject to finite element method according to the present invention.
- FIG. 3 is a single dimensional temperature distribution chart obtained by means of insertion of a silica capillary and a Cr:YAG crystal fiber in a sapphire tube and heating of the sapphire tube with laser subject to finite element method according to the present invention.
- FIG. 4 illustrates the growth of crystal and the related equipment subject to LHPG method according to the present invention.
- FIG. 5 is a core diameter-laser power curve obtained from the fabrication of a double-clad crystal fiber by means of direct heating according to the present invention.
- FIG. 6 is a core diameter-laser power curve obtained from the fabrication of a double-clad crystal fiber by means of sapphire tube radiation heating according to the present invention.
- FIG. 7 is a core diameter-core variation curve obtained from the fabrication of a double-clad crystal fiber with and without sapphire tube according to the present invention.
- An indirect heat type double-clad optical fiber fabrication method in accordance with the present invention is as follows:
- a crystal fiber at first, and then insert the crystal fiber into a silica capillary, and then attach a sapphire tube to the periphery of the part of the silica capillary to be heated, and then apply a laser beam to the sapphire tube to increase the temperature of the sapphire tube and to further fuse the silica capillary with thermal radiation so that the fused silica capillary is wrapped about the crystal fiber, forming the desired double-clad optical fiber.
- finite element method was employed to simulate 2D temperature distribution by means of insertion of a silica capillary 20 and a Cr:YAG crystal fiber 30 in a sapphire tube 10 and heating of the sapphire tube with laser R.
- the sapphire tube has the length of 1.5 millimeters, the outer diameter of 1.2 millimeters, and the inner diameter of 0.48 millimeters.
- the silica capillary has the length of 100 millimeters, the outer diameter of 0.32 millimeter, and the inner diameter of 0.076 millimeter.
- Cr:YAG crystal fiber has the diameter of 0.076 millimeter.
- the temperature distribution is axis symmetrical.
- the result was as shown in FIGS. 2 and 3 .
- the temperature variation from the inside toward the outside is within 1° C. This explains an excellent thermal capacitive effect that helps smooth heating of the silica capillary to grow a double-clad optical fiber having a uniform diameter.
- FIG. 4 illustrates the growth of crystal and the related equipment subject to LHPG method.
- the invention also uses this equipment.
- the actual performance is as follows:
- a Cr:YAG crystal fiber having the diameter of 0.07 millimeter then insert the Cr:YAG crystal fiber into a silica capillary of outer diameter 0.32 millimeter and inner diameter 0.076 millimeter, and then set a sapphire tube of length 1.5 millimeter, outer diameter 1.2 millimeter and inner diameter 0.48 millimeter in the laser focus, and then apply CO 2 laser to the sapphire tube within the height about 0.44 millimeter to produce thermal radiation, thereby heating the silica capillary, causing the fused silica capillary to be wrapped about the crystal fiber, and therefore the desired double-clad optical fiber is thus obtained.
- the crystal fiber material can be glass or crystal.
- the Cr:YAG crystal fiber is used as a thermal capacitor that stabilizes wave motion of CO 2 laser, and is free from the wave motion of laser power for heating the silica capillary indirectly to grow a double-clad crystal fiber having a uniform diameter and a core smaller than 10 micrometer.
- the laser power required for heating silica capillary indirectly with thermal radiation is about one tenth of the laser power required for heating silica capillary directly with laser beam.
- the change of core diameter relative to laser power in the growth of double-clad crystal fiber with or without sapphire tube is observed.
- a double-clad crystal fiber without a sapphire tube shows a change of 58.9% in core diameter when laser power is changed by 1%.
- a double-clad crystal fiber with a sapphire tube shows a change of 5.88% in core diameter when laser power is changed by 1%.
- the thermal capacitance effect of the sapphire tube effectively improves the problem of significant variation of the core diameter with the variation of the applied laser power.
- the application of the present invention can grow a double-clad crystal fiber of core diameter 5 ⁇ 25 ⁇ m.
- Reducing core diameter to below 5 ⁇ m has the benefits of: (a) reducing the number of modes and lowering transmission loss, and (b) improving the conversion efficiency of Cr:YAG crystal fiber in spontaneous emission to amplify light source. Further, when fused with glass fiber, it greatly reduces insertion loss due to a different core sectional area.
- Cr:YAG double-clad crystal fiber can be used for making high-efficiency, low transmission loss spontaneous emission optical amplifier for all-optical network.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
- Lasers (AREA)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/659,792 US8001806B2 (en) | 2006-08-25 | 2010-03-22 | Indirect heat type double-clad crystal fiber fabrication method |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| TW95131451 | 2006-08-25 | ||
| TW095131451A TW200811494A (en) | 2006-08-25 | 2006-08-25 | Method for fabricating indirect-heated double-clad crystal fiber |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US12/659,792 Continuation US8001806B2 (en) | 2006-08-25 | 2010-03-22 | Indirect heat type double-clad crystal fiber fabrication method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US20080047303A1 true US20080047303A1 (en) | 2008-02-28 |
Family
ID=39112088
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US11/590,778 Abandoned US20080047303A1 (en) | 2006-08-25 | 2006-11-01 | Indirect heat type double-clad crystal fiber fabrication method |
| US12/659,792 Expired - Fee Related US8001806B2 (en) | 2006-08-25 | 2010-03-22 | Indirect heat type double-clad crystal fiber fabrication method |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US12/659,792 Expired - Fee Related US8001806B2 (en) | 2006-08-25 | 2010-03-22 | Indirect heat type double-clad crystal fiber fabrication method |
Country Status (2)
| Country | Link |
|---|---|
| US (2) | US20080047303A1 (zh) |
| TW (1) | TW200811494A (zh) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110100066A1 (en) * | 2008-05-19 | 2011-05-05 | Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V | Device for joining and tapering fibers and other optical components |
| US9195002B2 (en) | 2012-09-14 | 2015-11-24 | National Taiwan University | Double cladding crystal fiber and manufacturing method thereof |
| EP3054337A1 (en) | 2015-02-09 | 2016-08-10 | National Taiwan University | Three-dimensional optical coherence tomography apparatus and its application |
| CN108947233A (zh) * | 2018-06-28 | 2018-12-07 | 华南理工大学 | 一种掺钛蓝宝石非晶光纤及其制备方法和应用 |
| CN114409243A (zh) * | 2022-01-17 | 2022-04-29 | 北京工业大学 | 一种掺杂yag衍生玻璃光纤的制备方法 |
| US20220349085A1 (en) * | 2020-11-19 | 2022-11-03 | Crystal Systems Corporation | Single-Crystal Fiber Production Equipment and Single-Crystal Fiber Production Method |
| KR20230118717A (ko) * | 2020-12-15 | 2023-08-14 | 크리스탈 시스템스 코포레이션 | 박판상 단결정 제조 장치 및 박판상 단결정 제조 방법 |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI402548B (zh) * | 2008-08-25 | 2013-07-21 | Univ Nat Sun Yat Sen | 具有多模光纖放大器及單模光纖之光纖系統及其寬頻耦光方法 |
| JP5921445B2 (ja) * | 2010-01-15 | 2016-05-24 | コラクティブ・ハイ−テック・インコーポレイテッドＣｏｒａｃｔｉｖｅ Ｈｉｇｈ−Ｔｅｃｈ Ｉｎｃ． | ストリップ部がシールされた二重クラッド光ファイバ |
| TWI461768B (zh) * | 2012-11-01 | 2014-11-21 | Univ Nat Sun Yat Sen | 光纖製作方法及其光纖 |
| CN109799572B (zh) * | 2018-12-12 | 2020-12-04 | 桂林电子科技大学 | 一种纤维集成的高斯-环形模场适配器 |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US3877912A (en) * | 1973-10-09 | 1975-04-15 | Sumitomo Electric Industries | Method of producing an optical transmission line |
| US4040890A (en) * | 1975-06-27 | 1977-08-09 | Bell Telephone Laboratories, Incorporated | Neodymium oxide doped yttrium aluminum garnet optical fiber |
| US4283213A (en) * | 1979-10-22 | 1981-08-11 | International Telephone And Telegraph Corporation | Method of fabrication of single mode optical fibers or waveguides |
| US4289516A (en) * | 1979-10-04 | 1981-09-15 | Eotec Corporation | Low loss optical fibers |
| US4547650A (en) * | 1982-12-10 | 1985-10-15 | Thomson-Csf | Device for heating an annular surface zone of a threadlike object |
| US4954152A (en) * | 1988-12-19 | 1990-09-04 | Hughes Aircraft Company | High strength optical fiber splice |
| US5077087A (en) * | 1988-04-25 | 1991-12-31 | The Board Of Trustees Of The Leland Stanford Junior Univ. | Method of cladding single crystal optical fiber |
| US5177803A (en) * | 1991-04-29 | 1993-01-05 | Corning Incorporated | Coaxial optical fiber coupler transmitter-receiver apparatus and method of making same |
| US5187761A (en) * | 1990-05-22 | 1993-02-16 | France Telecom | Method of making an inlet cone on a connection endpiece for optical fibers, and apparatus for performing the method |
| US5339372A (en) * | 1993-06-09 | 1994-08-16 | Corning Incorporated | Low loss coupler |
| US5509952A (en) * | 1992-11-23 | 1996-04-23 | Alcatel Network Systems, Inc. | Method for bonding a fiber to a sleeve for fiber optic packaging applications |
| US6626011B2 (en) * | 1995-11-13 | 2003-09-30 | Alcatel | Method of manufacturing a monomode fluoride optical fiber, and an optical amplifier using such a fiber |
| US6777358B2 (en) * | 2002-07-25 | 2004-08-17 | Nortel Networks Limited | Sealing glass composition |
| US7430881B2 (en) * | 2003-01-10 | 2008-10-07 | Weatherford/Lamb, Inc. | Method of making an optical fiber attachment device |
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| US4407668A (en) * | 1977-09-30 | 1983-10-04 | Siemens Aktiengesellschaft | Apparatus and process for producing a cladded optical fiber having a longitudinal side coupling zone |
| US4961768A (en) * | 1989-04-20 | 1990-10-09 | Djeu Nicholas I | Methods for bonding optical fibers to wafers |
| US7266259B1 (en) * | 2004-03-24 | 2007-09-04 | Fitel U.S.A. Corp. | Optical fiber microcoil, resonant structure and method of making the same |
| US20050279526A1 (en) * | 2004-06-17 | 2005-12-22 | Johnson Douglas E | Cable and method of making the same |
| US7352949B2 (en) * | 2004-11-24 | 2008-04-01 | National Sun Yat-Sen University | Fiber used in wideband amplified spontaneous emission light source and the method of making the same |
| US7306376B2 (en) * | 2006-01-23 | 2007-12-11 | Electro-Optics Technology, Inc. | Monolithic mode stripping fiber ferrule/collimator and method of making same |
-
2006
- 2006-08-25 TW TW095131451A patent/TW200811494A/zh not_active IP Right Cessation
- 2006-11-01 US US11/590,778 patent/US20080047303A1/en not_active Abandoned
-
2010
- 2010-03-22 US US12/659,792 patent/US8001806B2/en not_active Expired - Fee Related
Patent Citations (14)
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|---|---|---|---|---|
| US3877912A (en) * | 1973-10-09 | 1975-04-15 | Sumitomo Electric Industries | Method of producing an optical transmission line |
| US4040890A (en) * | 1975-06-27 | 1977-08-09 | Bell Telephone Laboratories, Incorporated | Neodymium oxide doped yttrium aluminum garnet optical fiber |
| US4289516A (en) * | 1979-10-04 | 1981-09-15 | Eotec Corporation | Low loss optical fibers |
| US4283213A (en) * | 1979-10-22 | 1981-08-11 | International Telephone And Telegraph Corporation | Method of fabrication of single mode optical fibers or waveguides |
| US4547650A (en) * | 1982-12-10 | 1985-10-15 | Thomson-Csf | Device for heating an annular surface zone of a threadlike object |
| US5077087A (en) * | 1988-04-25 | 1991-12-31 | The Board Of Trustees Of The Leland Stanford Junior Univ. | Method of cladding single crystal optical fiber |
| US4954152A (en) * | 1988-12-19 | 1990-09-04 | Hughes Aircraft Company | High strength optical fiber splice |
| US5187761A (en) * | 1990-05-22 | 1993-02-16 | France Telecom | Method of making an inlet cone on a connection endpiece for optical fibers, and apparatus for performing the method |
| US5177803A (en) * | 1991-04-29 | 1993-01-05 | Corning Incorporated | Coaxial optical fiber coupler transmitter-receiver apparatus and method of making same |
| US5509952A (en) * | 1992-11-23 | 1996-04-23 | Alcatel Network Systems, Inc. | Method for bonding a fiber to a sleeve for fiber optic packaging applications |
| US5339372A (en) * | 1993-06-09 | 1994-08-16 | Corning Incorporated | Low loss coupler |
| US6626011B2 (en) * | 1995-11-13 | 2003-09-30 | Alcatel | Method of manufacturing a monomode fluoride optical fiber, and an optical amplifier using such a fiber |
| US6777358B2 (en) * | 2002-07-25 | 2004-08-17 | Nortel Networks Limited | Sealing glass composition |
| US7430881B2 (en) * | 2003-01-10 | 2008-10-07 | Weatherford/Lamb, Inc. | Method of making an optical fiber attachment device |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110100066A1 (en) * | 2008-05-19 | 2011-05-05 | Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V | Device for joining and tapering fibers and other optical components |
| US9195002B2 (en) | 2012-09-14 | 2015-11-24 | National Taiwan University | Double cladding crystal fiber and manufacturing method thereof |
| EP3054337A1 (en) | 2015-02-09 | 2016-08-10 | National Taiwan University | Three-dimensional optical coherence tomography apparatus and its application |
| CN108947233A (zh) * | 2018-06-28 | 2018-12-07 | 华南理工大学 | 一种掺钛蓝宝石非晶光纤及其制备方法和应用 |
| US20220349085A1 (en) * | 2020-11-19 | 2022-11-03 | Crystal Systems Corporation | Single-Crystal Fiber Production Equipment and Single-Crystal Fiber Production Method |
| KR20230107726A (ko) * | 2020-11-19 | 2023-07-18 | 크리스탈 시스템스 코포레이션 | 단결정 파이버 제조 장치 및 단결정 파이버 제조 방법 |
| US11739435B2 (en) * | 2020-11-19 | 2023-08-29 | Crystal Systems Corporation | Single-crystal fiber production equipment and single-crystal fiber production method |
| KR102789749B1 (ko) * | 2020-11-19 | 2025-03-31 | 크리스탈 시스템스 코포레이션 | 단결정 파이버 제조 장치 및 단결정 파이버 제조 방법 |
| KR20230118717A (ko) * | 2020-12-15 | 2023-08-14 | 크리스탈 시스템스 코포레이션 | 박판상 단결정 제조 장치 및 박판상 단결정 제조 방법 |
| KR102759972B1 (ko) * | 2020-12-15 | 2025-01-23 | 크리스탈 시스템스 코포레이션 | 박판상 단결정 제조 장치 및 박판상 단결정 제조 방법 |
| CN114409243A (zh) * | 2022-01-17 | 2022-04-29 | 北京工业大学 | 一种掺杂yag衍生玻璃光纤的制备方法 |
Also Published As
| Publication number | Publication date |
|---|---|
| TWI318305B (zh) | 2009-12-11 |
| TW200811494A (en) | 2008-03-01 |
| US8001806B2 (en) | 2011-08-23 |
| US20100229604A1 (en) | 2010-09-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: NATIONAL SUN YAT-SEN UNVERSITY, TAIWAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:HUANG, KWANG-YAO;LO, CHIA-YAO;HUANG, SHENG-LUNG;REEL/FRAME:018489/0348 Effective date: 20061020 |
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| STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |