GB2071351A - Manufacture of monomode fibers - Google Patents
Manufacture of monomode fibers Download PDFInfo
- Publication number
- GB2071351A GB2071351A GB8016278A GB8016278A GB2071351A GB 2071351 A GB2071351 A GB 2071351A GB 8016278 A GB8016278 A GB 8016278A GB 8016278 A GB8016278 A GB 8016278A GB 2071351 A GB2071351 A GB 2071351A
- Authority
- GB
- United Kingdom
- Prior art keywords
- fiber
- tube
- core
- phosphorus
- fused silica
- 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.)
- Withdrawn
Links
- 239000000835 fiber Substances 0.000 title claims abstract description 63
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 52
- 238000005253 cladding Methods 0.000 claims abstract description 45
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 claims abstract description 23
- 239000005350 fused silica glass Substances 0.000 claims abstract description 23
- 229910052698 phosphorus Inorganic materials 0.000 claims abstract description 23
- 239000011574 phosphorus Substances 0.000 claims abstract description 23
- 229910052732 germanium Inorganic materials 0.000 claims abstract description 12
- GNPVGFCGXDBREM-UHFFFAOYSA-N germanium atom Chemical compound [Ge] GNPVGFCGXDBREM-UHFFFAOYSA-N 0.000 claims abstract description 12
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 16
- 239000001301 oxygen Substances 0.000 claims description 16
- 229910052760 oxygen Inorganic materials 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 8
- 238000000151 deposition Methods 0.000 claims description 6
- VXEGSRKPIUDPQT-UHFFFAOYSA-N 4-[4-(4-methoxyphenyl)piperazin-1-yl]aniline Chemical compound C1=CC(OC)=CC=C1N1CCN(C=2C=CC(N)=CC=2)CC1 VXEGSRKPIUDPQT-UHFFFAOYSA-N 0.000 claims description 5
- 239000005049 silicon tetrachloride Substances 0.000 claims description 5
- 239000007787 solid Substances 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 239000013307 optical fiber Substances 0.000 claims description 4
- 239000002019 doping agent Substances 0.000 claims description 3
- 239000011521 glass Substances 0.000 claims description 3
- 239000011236 particulate material Substances 0.000 claims description 3
- 229910052710 silicon Inorganic materials 0.000 claims 5
- 239000010703 silicon Substances 0.000 claims 5
- 239000011162 core material Substances 0.000 description 32
- 239000000377 silicon dioxide Substances 0.000 description 14
- XHXFXVLFKHQFAL-UHFFFAOYSA-N phosphoryl trichloride Chemical compound ClP(Cl)(Cl)=O XHXFXVLFKHQFAL-UHFFFAOYSA-N 0.000 description 6
- 230000008021 deposition Effects 0.000 description 5
- 239000006185 dispersion Substances 0.000 description 5
- 238000013461 design Methods 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 235000012239 silicon dioxide Nutrition 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 238000005229 chemical vapour deposition Methods 0.000 description 3
- 230000003595 spectral effect Effects 0.000 description 3
- 239000000654 additive Substances 0.000 description 2
- 230000000996 additive effect Effects 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000012806 monitoring device Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- IEXRMSFAVATTJX-UHFFFAOYSA-N tetrachlorogermane Chemical compound Cl[Ge](Cl)(Cl)Cl IEXRMSFAVATTJX-UHFFFAOYSA-N 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000005587 bubbling Effects 0.000 description 1
- 239000012159 carrier gas Substances 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
Classifications
-
- 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
- G02B6/036—Optical fibres with cladding with or without a coating core or cladding comprising multiple layers
- G02B6/03616—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference
- G02B6/03622—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference having 2 layers only
- G02B6/03633—Optical fibres characterised both by the number of different refractive index layers around the central core segment, i.e. around the innermost high index core layer, and their relative refractive index difference having 2 layers only arranged - -
-
- 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
- C03B37/01211—Manufacture of preforms for drawing fibres or filaments starting from tubes, rods, fibres or filaments by inserting one or more rods or tubes into a tube
-
- 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]
- C03B37/018—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] by glass deposition on a glass substrate, e.g. by inside-, modified-, plasma-, or plasma modified- chemical vapour deposition [ICVD, MCVD, PCVD, PMCVD], i.e. by thin layer coating on the inside or outside of a glass tube or on a glass rod
- C03B37/01807—Reactant delivery systems, e.g. reactant deposition burners
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C13/00—Fibre or filament compositions
- C03C13/04—Fibre optics, e.g. core and clad fibre compositions
- C03C13/045—Silica-containing oxide glass compositions
-
- 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
- G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
- G02B6/102—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type for infrared and ultraviolet radiation
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/02—Pure silica glass, e.g. pure fused quartz
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/20—Doped silica-based glasses doped with non-metals other than boron or fluorine
- C03B2201/28—Doped silica-based glasses doped with non-metals other than boron or fluorine doped with phosphorus
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2201/00—Type of glass produced
- C03B2201/06—Doped silica-based glasses
- C03B2201/30—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi
- C03B2201/31—Doped silica-based glasses doped with metals, e.g. Ga, Sn, Sb, Pb or Bi doped with germanium
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B2203/00—Fibre product details, e.g. structure, shape
- C03B2203/10—Internal structure or shape details
- C03B2203/22—Radial profile of refractive index, composition or softening point
- C03B2203/24—Single mode [SM or monomode]
Abstract
A monomode fiber 11 has a core 14, cladding layer 15 and jacketing layer 16. The cladding layer has a refractive index which is a predetermined value lower than that of the core and a predetermined value higher than that of the jacketing layer. The jacket can be formed by a fused silica tube, the cladding layer of phosphorus doped fused silica and the core of doped fused silica, being doped with either phosphorus or germanium, or both. The manufacture of the fibre is described. <IMAGE>
Description
SPECIFICATION
Manufacture of monomode fibers
This invention relates to monomode optical fibers and is concerned with a particular form of such a fiber.
The bandwidth of a multi mode optical fiber is limited by intermodal dispersion and by chromatic dispersion. The intermodal dispersion can be minimized by closely equalizing optical path lengths of various modes. To achieve this, the index profile across the fiber core has to be controlled very precisely. In the currently used fiber fabrication technologies, it is difficult to achieve the optimum index profile consistently.
Alternatively, intermodal dispersion can be eliminated entirely by restricting the guided mode to the lowest order mode (monomode fiber).
The chromatic dispersion is determined mainly by the intrinsic property of the materials used to construct the fiber and the spectral bandwidth of the light source. In silica-based glasses, the chromatic effect is minimal at the wavelength of approximately 1.3 ,um( 1 ).
In monomode fibers, a larger portion of the guided light is carried through the cladding layer compared to the multimode fibers. Therefore, both core and cladding materials have to be chemically deposited to minimize the attenuation.
Boron-doped silica has been commonly used for the cladding because of its lower refractive index relative to the pure silica used for the core.
A drawback of this fiber design is the high attenuation at the wavelength range of 1.3 Mm due to the intrinsic optical absorption of borondoped silica. Pure silica is the only cladding material used to date to make a monomode fiber with a low attenuation at the wavelength of
1.3 Xtzm. The core is made of either germanium or phosphorus doped silica. In this design, the
depositions of the cladding requires a sustained
high temperature which tends to give rise to serious distortion of the substrate tube with subsequent deformation of the core and the
cladding. This technical difficulty can be overcome by utilizing sophisticated tube diameter
monitoring and pressure-controlling systems.
A theoretical requirement to design monomode fiber is given by V-value defined by: 27daNA
V= A
For the operating wavelength (A), the core radius (a) and the numerical aperture (NA) have to be chosen to make the V-value smaller than 2.405 for step-index profiles. For a parabolic profile,
V < 3.518; other profiles will have their unique maximal V-values. To minimize losses due to input coupling, jointing, and bending, it is desirable to choose the core size and NA as large as possible without violating the monomode requirement.
However, even if the V value is slightly larger than the cut-off value, higher modes are usually lossy.
Practically such a quasi-monomode fiber can operate as a monomode fiber for a sufficiently long fiber length.
By utilizing an appropriate choice of dopants and a new fiber design, monomode fibers with low loss at the 1.3 Mm wavelength range can be fabricated. The modified chemical vapour deposition technique, well established for multi mode fiber fabrication can be used without any special modifications.
Phosphorus is incorporated into the silica cladding layer as a flux, the amount being chosen to satisfy the following two requirements: the deposition temperature being sufficiently low so as to avoid any distortion of the substrate tube, and the refractive index increase sufficiently small so as to minimize the amount of light carried through the cladding layer, which has a refractive index slightly higher than that of the substrate silica tube. In a particular example, a germanium doped silica core is deposited following the phosphorus doped silica cladding deposition.
In its broadest aspect, the present invention provides a monomode fiber comprising core, cladding layer and jacketing layer. The cladding layer has a refractive index which is a predetermined value lower than that of the core and a predetermined value higher than that of the jacketing layer.
The invention will be readily understood by the following description of certain embodiments, by way of example in conjunction with the accompanying drawings, in which: Figures 1 and 2 are cross-sections through conventional forms of multimode and monomode fibers,
Figures 3 and 4 are diagrammatic representations of the refractive index of the two know forms of monomode fiber, being representative of across a fiber parallel to the longitudinal axis of the fiber;
Figure 5 is a diagrammatic representation of the refractive index across a fiber in accordance with the present invention;
Figure 6 is a typical spectral attenuation curve of a fiber, in accordance with the present invention;
Figure 7 is a diagrammatic illustration of one form of apparatus for rr,Pking a preform for drawing into a fiber.
Figures 1 and 2 illustrate a multimode fiber 10 and a monomode fiber 11 respectively. The multimode fiber 10 has a core 12 and a cladding layer 13. Typically the cladding can be fused silica and the core doped fused silica having a refractive index slightly higher than that of the cladding.
Alternatively the core can be fused silica and the cladding of doped fused silica, doped so as to have a lower refractive index than the core. Typical dimensions are 50 Mm for the core diameter and 125 Mm for the outside diameter of the cladding, although these dimensions can vary.
The monomode fiber 11 has a core 14, a cladding layer 1 5 and a jacket 1 6. Typical dimensions for fiber 11 are approximately 10 ,um for the diameter of the core, 50 to 70 um for the outside diameter of the cladding and 125-1 50 rm for the outside diameter of the jacket. These dimensions may vary slightly. It will be seen that the total quantity of deposited material is approximately the same in both monomode and multimode fibers, that is, the core 12 in the multimode fiber and the core 14 and cladding 1 5 in the monomode fiber.
For the monomode fiber, 11, as stated previously, boron-doped silica has been used for the cladding with pure silica for the core, deposited in a pure silica tube, for example The index of refraction profile for such a fiber is illustrated in Figure 3. Such a fiber has high attenuation at the wavelength range 1.3,us. For low attenuation at 1.3 ssm, pure fused silica has been used for the cladding layer. The core is of either germanium or phosphorus doped silica. The index of refraction profile for this latter form of fiber is illustrated in Figure 4.
The present invention provides a form of fiber which avoids the high attenuation characteristics of boron-doped silica cladding (Figures 2 s 3) and also avoids the manufacturing problems of pure fused silica cladding (Figures 2 a 4). The jacket,
16 in Figure 2, is of pure fused silica, for example from an original fused silica tube substrate, the cladding is of doped silica, phosphorus being used as a dopant and as a fusion temperature reducing flux or additive, and the core is also of doped fused silica, the core material being doped with either phosphorus or germanium or both.
With phosphorus doping, the doping level will be higher, in the core, than in the cladding. The resultant fiber has an index of refraction profile as in Figure 5. The core/clad light constitutes the monomode, but the cladding may also work as an effective multimode core utilizing the silica jacket as a cladding. However, for long fiber lengths (over
1 km), almost all of the lossy modes reflecting at the cladding/jacket interface are attenuated and only monomode light remains. Although the multimode cladding light is carried if the fiber is too short or if the amount of phosphorus in the
cladding is too large, such light can be eliminated by locally removing the silica jacket and applying a cladding mode stripper. This technique is used to
measure the attenuation of this type of
monomode fiber.
A typical spectral attenuation curve of a fiber in
accordance with the present invention is
illustrated in Figure 6.
Figure 7 illustrates one form of apparatus for
manufacturing preforms for drawing with fibers.
Silicon tetrachloride is held, in liquid form in
reservoir 20 and phosphorus oxychloride in liquid form in reservoir 21. Oxygen is fed, via pipe 22 and pipes 23 and 24 into reservoirs 20 and 21 respectively, the oxygen bubbling through the liquids in the reservoirs, and in so doing carrying vapour from each liquid. The oxygen and vapour from each reservoir passes through pipes 25 and 26 to a collecting chamber 27. Oxygen is also fed direct from pipe 22 directly to the collecting chamber 27 via pipe 28. A control valve 29 is provided in each pipe 23, 24 and 28. In pipes 25 and 26 a monitoring device 30 is provided to monitor the oxygen/vapour composition the monitoring devices controlling the valves 29 to maintain a preset composition by controlling the flow. Flow indicators 31 can also be provided, and a control valve 32 is provided in the oxygen pipe 28.
From the collating chamber 27 the mixed vapour and oxygen pass via pipe 33 to flow through a glass tube 34, of fused silica. The tube
34 is rotated and a flame from a torch or burner
35 is traversed up and down the tube, the burner fed oxygen and hydrogen via pipes 36 and 37
respectively. The gases and vapours dissociate as the burner is traversed to form a sooty or
particulate material, which then gives a resultant deposition, in the example of silica and
phosphorus, on the inner wall of the tube, in the form of a sooty deposit, which is fused onto the
inner wall in the form of a glassy film. This is a
conventional so-called modified chemical vapour
deposition method.
If phosphorus is to be added to both cladding
and core material, after the necessary number of
passes of the burner to deposit and form the
required thickness of cladding material, the supply
of phosphorus is increased and a further pass of the burner made to deposit the core material.
If the core material is to have a different
additive, for example, germanium, then a further
reservoir with associated piping control valve, and
monitor can be provided as indicated in dotted
outline, and with references 40, 41,42, 43 and 44
respectively. Then for forming the core material,
control valve 29 from the phosphorus oxychloride
reservoir is shut off and the control-valve for the
germanium tetrachloride reservoir is opened.
It is also possible to supply vapour containing
both phosphorus and germanium if desired. After
deposition of the core material, the tube 34 is
collapsed to a solid preform, by increasing the
temperature of the flame of the burner 35 to
collapse the tube by surface tension. The solid
preform can then be used for pulling into a fiber.
A typical example of making a fiber is as follows:
Flow rate of silicon tetrachloride approximately
100 cc/min; flow rate of phosphorus oxychloride
approximately 2 cc/min (total including carrier gas,
about 600 cc/min); number of passes, about 25;
temperature about 1 500 C. This forms a cladding
layer. Then a single pass to deposit the core
material is made as follows; silicon tetrachloride
about 75 cc/min; germanium tetrachloride about
23 cc/min; again at about 1 5000 C. The tube is
then collapsed by heating to about 21000C -- moving the burner slowing along the
tube.
The particular flow rates, relative values of the
constituents, and the temperatures are not critical
in so far as the present invention is concerned and
can vary in the manner as in other chemical
vapour depositions inside a tube. Other doping materials can be used, as in other processes.
After the tube is collapsed to a rod, it may be placed in a further tube and the combined tube and rod drawn to produce a fiber with desired core and cladding diameters. This is indicated in Figure 5 where the dotted lines 50 represent the refractive index of the tube. Alternatively, the preform may be drawn down into a fiber without insertion in a further tube.
Claims (19)
1. A monomode optical fiber comprising; a core of pure fused silica or doped fused silica, a cladding layer of doped fused silica or pure fused silica on the core, the relative doping of the core and the cladding layer being such that the
refractive index of the cladding layer is a
predetermined value lower than the refractive
index of the core; and a jacketing layer which has
a refractive index a predetermined value lower than that of the cladding layer.
2. A fiber as claimed in claim 1, including a further layer on the jacketing layer.
3. A fiber as claimed in claim 2, the further layer
having the same refractive index as the jacketing
layer.
4. A fiber as claimed in claim 1, 2 or 3, the jacketing layer being of pure fused silica, the cladding layer being of doped fused silica and the core being of doped fused silica.
5. A fiber as claimed in claim 4, the cladding layer being doped with phosphorus.
6. A fiber as claimed in claim 4, the core being doped with phosphorus.
7. A fiber as claimed in claim 4, the core being doped with germanium.
8. A fiber as claimed in claim 4, the core having an outside diameter of approximately 10 Mm and the cladding layer having an outside diameter of between about 50 fly and about 70 Mm.
9. A fiber as claimed in claim 8, the jacketing layer having an outside layer of between about
125 jam and about 150 jam.
10. A method of manufacturing a monomode fiber, comprising:
(i) mounting a fused silica tube for rotation about its axis;
(ii) passing a mixture of oxygen, silicon tetrachloride vapour and a vapour containing phosphorus through the tube;
(iii) rotating the tube and traversing a heating
means relative to the tube to form a localized heated area in the tube to dissociate the oxygen and the vapours, silicon being oxidized by the oxygen and phosphorus combining with the oxidized silicon in the heated area to form a particulate material, the material then depositing on the inner wall of the tube, the remainder of the oxygen and vapours flowing from the tube;
(iv) fusing the deposit on the inner wall to form a glassy film of fused silica with phosphorus as a dopant;
(v) continuing steps (iii) and (iv) a predetermined number of times;;
(vi) passing a mixture of oxygen, silicon tetrachloride vapour and a vapour containing at least one of phosphorus and germanium through the tube;
(vii) traversing the heating means relative to the tube while still rotating to form a localized heated area in the tube to dissociate the oxygen and the vapours, silicon being oxidized by the oxygen and at least phosphorus or germanium combining with the oxidized silicon in the heated area to form a particulate material, the material then being deposited on the inner wall on the fused deposit, the remainder of the oxygen and vapours flowing from the tube;
(viii) fusing the deposit to form a further glassy film of fused silica doped with at least phosphorus or germanium.
11. A method as claimed in claim 10 further comprising :- (ix) increasing the heating of the tube to collapse the tube to a solid rod.
12. A method as claimed in claim 11 further including drawing the solid rod to a fiber.
13. A method as claimed in claim 11 further including pushing the solid rod into a closely fitting glass tube.
14. A method as claimed in claim 13, further including drawing the tube and rod to a fiber.
1 5. A method as claimed in claim 10, wherein steps (vii) and (viii) are carried out once only.
1 6. A method as claimed in claim 10, wherein steps (iii) and (iv) are continued for about twentyfive passes.
17. A method as claimed in claim 10, in which both phosphorus and germanium combine with the oxidized silicon.
1 8. A monomode optical fiber substantially as hereinbefore described with reference to Figure 5 of the accompanying drawings.
19. A method of manufacturing a monomode fiber as claimed in claim 10 and substantially as hereinbefore described with reference to the accompanying drawings.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000334464A CA1122079A (en) | 1979-08-27 | 1979-08-27 | Manufacture of monomode fibers |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| GB2071351A true GB2071351A (en) | 1981-09-16 |
Family
ID=4115006
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8016278A Withdrawn GB2071351A (en) | 1979-08-27 | 1980-05-16 | Manufacture of monomode fibers |
Country Status (6)
| Country | Link |
|---|---|
| JP (1) | JPS5635108A (en) |
| CA (1) | CA1122079A (en) |
| GB (1) | GB2071351A (en) |
| IT (1) | IT1130698B (en) |
| NL (1) | NL8003105A (en) |
| SE (1) | SE8005973L (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2136239A (en) * | 1983-03-03 | 1984-09-12 | British Telecomm | Optical fibre transmission systems |
| GB2180059A (en) * | 1985-09-05 | 1987-03-18 | Stc Plc | Plasma spectroscopy |
| GB2185331A (en) * | 1985-09-02 | 1987-07-15 | Nippon Telegraph & Telephone | Single mode optical fibre |
| EP0256248A2 (en) * | 1986-06-27 | 1988-02-24 | AT&T Corp. | Depressed index cladding optical fiber cable |
| EP0260795A3 (en) * | 1986-08-08 | 1988-03-30 | American Telephone And Telegraph Company | Optical fiber |
| GB2228585A (en) * | 1989-02-28 | 1990-08-29 | Stc Plc | Silica optical fibre having two cladding layers |
| FR2741061A1 (en) * | 1995-11-13 | 1997-05-16 | Alcatel Fibres Optiques | METHOD FOR MANUFACTURING A MONOMODE OPTICAL FIBER AND OPTICAL AMPLIFIER USING SUCH A FIBER |
-
1979
- 1979-08-27 CA CA000334464A patent/CA1122079A/en not_active Expired
-
1980
- 1980-05-16 GB GB8016278A patent/GB2071351A/en not_active Withdrawn
- 1980-05-29 NL NL8003105A patent/NL8003105A/en not_active Application Discontinuation
- 1980-05-29 IT IT22414/80A patent/IT1130698B/en active
- 1980-08-05 JP JP10683680A patent/JPS5635108A/en active Pending
- 1980-08-26 SE SE8005973A patent/SE8005973L/en unknown
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2136239A (en) * | 1983-03-03 | 1984-09-12 | British Telecomm | Optical fibre transmission systems |
| GB2185331A (en) * | 1985-09-02 | 1987-07-15 | Nippon Telegraph & Telephone | Single mode optical fibre |
| US4755022A (en) * | 1985-09-02 | 1988-07-05 | Nippon Telegraph And Telephone Corporation | Zero dispersion single mode optical fiber with center core and side core in the 1.5 μm wavelength region |
| GB2185331B (en) * | 1985-09-02 | 1989-10-25 | Nippon Telegraph & Telephone | Single mode optical fiber |
| GB2180059A (en) * | 1985-09-05 | 1987-03-18 | Stc Plc | Plasma spectroscopy |
| EP0256248A2 (en) * | 1986-06-27 | 1988-02-24 | AT&T Corp. | Depressed index cladding optical fiber cable |
| EP0256248A3 (en) * | 1986-06-27 | 1989-09-13 | American Telephone And Telegraph Company | Depressed index cladding optical fiber cable |
| EP0260795A3 (en) * | 1986-08-08 | 1988-03-30 | American Telephone And Telegraph Company | Optical fiber |
| GB2228585A (en) * | 1989-02-28 | 1990-08-29 | Stc Plc | Silica optical fibre having two cladding layers |
| FR2741061A1 (en) * | 1995-11-13 | 1997-05-16 | Alcatel Fibres Optiques | METHOD FOR MANUFACTURING A MONOMODE OPTICAL FIBER AND OPTICAL AMPLIFIER USING SUCH A FIBER |
| WO1997018169A1 (en) * | 1995-11-13 | 1997-05-22 | Alcatel Alsthom Compagnie Generale D'electricite | Method for making a single-mode optical fibre and optical amplifier using said fibre |
| 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 |
Also Published As
| Publication number | Publication date |
|---|---|
| NL8003105A (en) | 1981-03-03 |
| CA1122079A (en) | 1982-04-20 |
| IT1130698B (en) | 1986-06-18 |
| JPS5635108A (en) | 1981-04-07 |
| IT8022414A0 (en) | 1980-05-29 |
| SE8005973L (en) | 1981-02-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4385802A (en) | Long wavelength, low-loss optical waveguide | |
| US4339174A (en) | High bandwidth optical waveguide | |
| US4217027A (en) | Optical fiber fabrication and resulting product | |
| CA2335879C (en) | Optical fiber preform having oh barrier and manufacturing method thereof | |
| US4909816A (en) | Optical fiber fabrication and resulting product | |
| US4802733A (en) | Fluorine-doped optical fibre and method of manufacturing such fibre | |
| EP0018704A1 (en) | Method of substantially continuously forming an optical waveguide preform and an optical waveguide | |
| GB2293822A (en) | Optical fibre preform | |
| US20080260339A1 (en) | Manufacture of depressed index optical fibers | |
| EP1642161A1 (en) | Optical fiber having reduced viscosity mismatch | |
| US4334903A (en) | Optical fiber fabrication | |
| CA1263550A (en) | Glad optical waveguide | |
| CN105911639B (en) | A kind of low decaying single mode optical fiber | |
| EP0028155B1 (en) | Single mode optical fibre and method of making it | |
| US4206968A (en) | Optical fiber and method for producing the same | |
| US6542690B1 (en) | Chalcogenide doping of oxide glasses | |
| CA2360918A1 (en) | Optical fiber preform having oh barrier and fabrication method thereof | |
| CA1122079A (en) | Manufacture of monomode fibers | |
| US4932990A (en) | Methods of making optical fiber and products produced thereby | |
| JPS6313944B2 (en) | ||
| US4747663A (en) | Monomode quartz glass light waveguide and method for producing it | |
| CA1128756A (en) | Method of fabricating optical fibers | |
| EP1183560A1 (en) | Chalcogenide doping of oxide glasses | |
| CA1246875A (en) | Process for eliminating the axial refractive index depression in optical fibres | |
| US4504299A (en) | Optical fiber fabrication method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |