CA1126548A - Optical fiber composition - Google Patents
Optical fiber compositionInfo
- Publication number
- CA1126548A CA1126548A CA332,751A CA332751A CA1126548A CA 1126548 A CA1126548 A CA 1126548A CA 332751 A CA332751 A CA 332751A CA 1126548 A CA1126548 A CA 1126548A
- Authority
- CA
- Canada
- Prior art keywords
- glass
- geo2
- optical fiber
- core
- amount
- 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.)
- Expired
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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
- C03B37/012—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]
-
- 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
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Geochemistry & Mineralogy (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Glass Compositions (AREA)
- Manufacture, Treatment Of Glass Fibers (AREA)
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
An optical fiber composed of a clad glass comprising mainly quartz glass and a core glass comprising mainly quartz glass having a higher refractive index than the clad glass, wherein the core glass is a quartz glass containing GeO2 and at least one dopant selected from the group consisting of P2O5, B2O3, TiO2, Al2O3, SiF4 and Ga2O3 the amount of GeO2 being less than about 15% by weight and the total amount of GeO2 and the other dopants being about 15% by weight or more. The optical fiber disclosed is an improved optical fiber having a wide transmission band and low transmission loss, which improved optical fiber can withstand the stresses accompanying thermal expansion,
An optical fiber composed of a clad glass comprising mainly quartz glass and a core glass comprising mainly quartz glass having a higher refractive index than the clad glass, wherein the core glass is a quartz glass containing GeO2 and at least one dopant selected from the group consisting of P2O5, B2O3, TiO2, Al2O3, SiF4 and Ga2O3 the amount of GeO2 being less than about 15% by weight and the total amount of GeO2 and the other dopants being about 15% by weight or more. The optical fiber disclosed is an improved optical fiber having a wide transmission band and low transmission loss, which improved optical fiber can withstand the stresses accompanying thermal expansion,
Description
65~8 1 BACKGROUND OF THE Tr~vENTIoN
1. Field of the Invention This invention relates to an optical fiber exhibiting low transmission loss and having a wide transmission band.
1. Field of the Invention This invention relates to an optical fiber exhibiting low transmission loss and having a wide transmission band.
2. Description of the Prior Art A typical optical fiber as shown in Fig. 1 is con-structed of a clad glass 2 and a core glass 1 having a higher refractive index than the clad glass.
; The principle of optical transmission by an optical fiber can be understood figuratively as confining the light in the core by the refractive index differential between the core and the clad glass. The transmission loss of an optical fiber is the result of absorption inherent to the materials used for the optical fiber, scattering, emission loss increased by the fiber bending, loss due to microbending, etc.
SUMMARY OF THE INVENTION
Accordingly, a principal object of the present in-vention is to provide an optical fiber having a wide trans-mission band and low transmission loss.
Another object of the present invention is to providea fiber which can withstand the stresses accompanying thermal expansion.
Still another object of the present invention is to provide a fiber containing amounts of additives such as ~eO2 and B203 such that an optimum balance of transmission properties is attained.
These and other objects of the present invention are accomplished with an optical fiber composed of a clad glass comprising mainly quartz glass and a core glass co~prising 6S4~
1 mainly quarkz g]ass l~aving a hi~her refractive index than the clad glass, wherein the core glass is a quartz glass contain-ing GeO2 and at leask one dopant selected from the group g 2 5~ B203, TiO2, ~12O3, SiF4 and Ga203 the amount of GeO2 being less than about 15% by weiyht and the total amount of GeO2 and the other dopants being about 15% by weight or more.
BRIEF DESCRIPTION OF THE DRA-~INGS
-Figure 1 is a cross-section of an optical fiber comprising a core 1 and a clad 2;
Figure 2 is a graph of the refractive index distribu-tion in the core oE an optical fiber;
Figure 3 is a schematic illustration showing a method for producing a fine glass particle body;
Figure 4 is a schematic illustration of the refract-ive index distribution in a fiber.
DETAILED DESCRIPTION OF THE INVENTION
As is well known in the art, GeO2, is added to the core glass in order to increase the refractive index of the core and thereby establish a refractive index difference hetween the core and the clad so as to provide an optical fiber having low transmission loss and wide transmission band. The refractive index increases in proprtion to the amount of GeO2 in the core. While small amounts of GeO2 may be present in the clad (as a result of incidental mixing of the GeO2 contained in the core) without defeating the purpose of the present invention, generally GeO2 is not positively added to the clad.
llZ~;5~8 1 If the coefficient of thermal expansion of the core 1 is substantially different than that of the clad 2, extremely large stress is generated between the core 1 and the clad 2, which can cause the composite member to split. In order to avoid this problem, the coefficient of thermal expansion is controlled by adding additives such as P2O5 and B2O3 to the core 1 which do not largely affect the refractive index of the core by comparison to the employment of GeO2 alone, but do reduce the softening temperature of the core. The addition of these additives is generally controlled such that the soften-ing temperature of the core is about 50 to 200 C lower than the clad and the coefficient of thermal expansion differential is 3 x 10 7~oC or less. The exact amounts added depend on several factors including the diameter of the preform and the perform and the type of optical fiber. Additives such as GeO2 and B2O3 are used in the present invention because they are accompanied by a minimum of light energy absorption and scattering.
Since scattering loss increases in proportion to the amount of the additives, the amount of additives such as GeO2, P2O5 and B2O3 in the core must be small in order to reduce scattering loss. On the other hand, the refractive index of the core should be increased in order to reduce microbending loss and emission loss. For this purpose the amount of addi-tives, in particular GeO2 should be increased.
Furthermore it is known that in an optical fiber the distribution of the refractive index of the core 1 varies across the diameter in the form of a parabola as shown in Fig.
2, and the transmission band (width) of the optical fiber is inversely proportional to the second power of the difference ~1.'Z65~3 1 (An) between the maximum va]ue of the refractive index of the core and the refractive index of the clad. In view of this, ~n should be small in order to broaden the transmission band and, thus, the amount of GeO2 should be maintained low. Thus, there is the dilemma that high amounts o-E GeO2 are required in the core in order to increase its refractive index and reduce transmission loss but if too high an amount of GeO2 is present in the core an increases which leads to a narrower transmission band width.
As can be understood from the foregoing, the amount of the additives in an optical fiber having low transmission loss and a broad transmission band must be balanced and confinecl to certain ranges.
One example of a method of producing a preform for optical fibers by a flame hydrolyzing process is described below.
This manufacturing method is shown schematically in Fig. 3. From a first nozzle 3 and a second nozzle 4, a gaseous glass-forming material containing additives providing a higher refractive index than SiO2 (for example, a mixture of SiC14, GeC14, PoC13, and ~Br3) and a gaseous glass-forming material containing additives providing a lower refractive index than SiO2 (for example, a mixture of SiC14 and BBr3) are blown to-yether with a heat combustion gas (for example, oxygen and hydro-gen, butane and propane). The glass-forming material gasses are flame-hydrolyzed outside the multiple nozzles to forrn fine glass particles which accumulate on a starting rod 5. A fine glass particle body 6 is then grown in the axial direction. Tlle fine glass particle body gradually falls into a high temperature furnace having a temperature of 1400 to 1600 C whereby the glass particle body is sintered and vitrified thereby producing a 2654~3 1 preform for an optical glass fiber.
As shown in Fig. 2, the resulting preform for optical fibers has a refractive index distribution in the form of a parabola from the core 1.
The distribution of additives in a cross-section of a core glass is not uniform and the coefficient of thermal expansion also varies across the cross-section. If the co-efficient of thermal expansion varies greatly, stress occurs upon sintering the fine glass particle body 6 causing the fine glass particle body to crack. Furthermore, the preform tends to crack easily when the preform is removed from the high temp-erature furnace after the sintering, or at the time of preform-ing other heat-treatments.
In forming SiO2 glass containing GeO2 by flame-hydro-lyzed reaction, a noticeahle phenomena is recognized. That is, a solid solution is formed between GeO2 and SiO2, and a part of GeO2 i5 precipitated into crystals in the form of a hexagonal system. The hexagonal system GeO2 has a melting point of about 1086C which is much lower than the melting point of SiO2 (l6oooc to 1700C). Therefore, bubbles of vaporized GeO2 are apt to be formed by thermal treatment during draw forming operation of such core materials to obtain glass fibers. If such bubbles are generated transmission loss becomes large. The probahility of generation of bubbles ls large at higher con-centrations of GeO2- Various experiments have shown GeO2 amount should be less than 15 wt~, by which the generation of bubbles is negligible and low transmission loss is obtained.
Furthermore, if the central portion of the fine glass particle body 6 has a higher melting point than that of the outcr peripheral portion tllereof, sintering of the glass 1~ti5~
1 particle body will begin vitrification at the surface of the body making it difficult to drive off bubbles in the central portion completely. Hence bubbles tend to remain in the central portion and cause scattering loss in the optical fibers. To prevent these bubbles from forming, glass particle body 6 is produced by varying the amount of additives at the central portion and the peripheral portion within the above range, and sinter~d.
As will be understood from the above, the amounts of additives in the core portions of the preform for optical fibers are limited to certain ranges. When a fine glass particle body 6 containing 5 to 15% by weight of GeO2 at the core and contain-ing O to 10% by weight P205 and B203 was sintered, a very good preform for optical fibers was obtained. Furthermore, a good preform for optical fibers was obtained from glass particle body 6 containing 15% by weight or more in total of GeO2, l'25 and ~23 at the core. By adjusting the amount of GeO2 to adjust Qn (in this field to about 0.9 to 1.2%)(which is closely related to the transmission loss and the transmission band) to less than ~ 15% by weight, a preform foroptical fibers having high quali-ty with a transmission loss of not more than 3.0ds/km (at 0.85 micromèter) and a transmission band of at least 40~Hz km0~75 (0.75th power) was obtained.
In the above experiments, GeO2, P205 and B203 ~e~e used as additives for the clad glass. The amounts of the addj-tives in the clad glass should be properly adjusted depending upon the composition of the core portion. These additives are not restricted to GeO2, P205 and B203 as it will be recognized from the foregoing that other additives permitting low loss and low scattering which can control the rcfractive index, the ;S48 1 coefficient of thermal expansion and the meltiny point, such as TiO2~ ~1203, SiF4 and Ga203 can also be used. Furthermore, the clad may be pure quartz glass consistiny of SiO2-While the above description has been directed tograded index optical fibers in which the refractive index of the core varies in the form of a parabola as shown in Figure 2, the above experimental facts are also applicable to optical fibers.
The following Examples illustrate the present inven-tion in more detail. Unless otherwise indicated all percentagesare by weight.
COMPARATIVE E ~ IPLE 1 Amount of base material SiO2 86.70%
Amount of additives for the core glass:
GeO2 12%
P205 0-3%
B203 1~6 , Total 13.3%
Amount of base material SiO2 95%
Amount of an additive for the clad glass:
B2 3 5%
A fine glass particle body having the above composition was produced and sintered. Cracks occurred in the clad glass.
Amount of base material SiO2 88.89 Amount of additives at the core glass:
G~02 8.2%
P205 0.51%
S4t~
1Comparative Example 2 continued l323 2.4%
Total 11.11%
Amount of base material SiO2 92%
Amount of an additive for the clad glass:
B2O3 8%
A fine glass particle body having the above composi-tion was produced and sintered in a high temperature furnace at 1550 C. A porous portion remained in the core portion and a completely solid preform for optica] fibers could not be obtain-ed.
EXAr~PLE 1 Amount of base material SiO2 79.27%
Amount of additives for the core glass:
GeO2 13.8%
P205 0.53%
B203 6.4%
Total 20.73%
Amount of base material SiO2 93.42%
Amount of additlves for the clad glass:
GeO2 3.5%
P2P5 0.28%
~23 2.8%
Total 6.58%
A fine glass body having the above composition was produced and sintered in a furnace at 1500C. A ~ood preform for optical fibers was obtained. The preform was spun in~o a fiber having an outer diameter of 150 microns. The transmission loss and the transmission band of the fib~r per kilometer ~rere --8~
~ `` liZ~;5~8 1 4.5dB/km (loss at 0.~3 micrometer) and 225L~Z-km, respectively.
E~AMPLE 2 Amount of base material sio2 81.72 Amount of additives for the core glass:
GeO2 12.5%
P2O5 0.48%
23 5.3%
Total 18.28%
Amount of base material SiO2 90.02%
Amount of additives for the clad glass:
GeO2 3.2~
P2O5 0.38%
B2O3 6.4%
Total 9.98%
A fine glass particle body having the above composi-tion was produced and sintered in a furnace at 1550C. ~ good preform for optical fibers was obtained. The preform was stretched to have a diameter of lOmm, and inserted into a ~0 quartz pipe having an inner diameter of llmm and an outer dia-meter of 20mm. The two were fused with each other and spun into a fiber haviny an outer diameter of 150 micrometers. The transmission loss and the transmission band of this fiber were 2.64dB/km (loss at 0.83 micrometer) and 405MHz-km (0.75 power:
coefficient for distance conversion), respectively.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and
; The principle of optical transmission by an optical fiber can be understood figuratively as confining the light in the core by the refractive index differential between the core and the clad glass. The transmission loss of an optical fiber is the result of absorption inherent to the materials used for the optical fiber, scattering, emission loss increased by the fiber bending, loss due to microbending, etc.
SUMMARY OF THE INVENTION
Accordingly, a principal object of the present in-vention is to provide an optical fiber having a wide trans-mission band and low transmission loss.
Another object of the present invention is to providea fiber which can withstand the stresses accompanying thermal expansion.
Still another object of the present invention is to provide a fiber containing amounts of additives such as ~eO2 and B203 such that an optimum balance of transmission properties is attained.
These and other objects of the present invention are accomplished with an optical fiber composed of a clad glass comprising mainly quartz glass and a core glass co~prising 6S4~
1 mainly quarkz g]ass l~aving a hi~her refractive index than the clad glass, wherein the core glass is a quartz glass contain-ing GeO2 and at leask one dopant selected from the group g 2 5~ B203, TiO2, ~12O3, SiF4 and Ga203 the amount of GeO2 being less than about 15% by weiyht and the total amount of GeO2 and the other dopants being about 15% by weight or more.
BRIEF DESCRIPTION OF THE DRA-~INGS
-Figure 1 is a cross-section of an optical fiber comprising a core 1 and a clad 2;
Figure 2 is a graph of the refractive index distribu-tion in the core oE an optical fiber;
Figure 3 is a schematic illustration showing a method for producing a fine glass particle body;
Figure 4 is a schematic illustration of the refract-ive index distribution in a fiber.
DETAILED DESCRIPTION OF THE INVENTION
As is well known in the art, GeO2, is added to the core glass in order to increase the refractive index of the core and thereby establish a refractive index difference hetween the core and the clad so as to provide an optical fiber having low transmission loss and wide transmission band. The refractive index increases in proprtion to the amount of GeO2 in the core. While small amounts of GeO2 may be present in the clad (as a result of incidental mixing of the GeO2 contained in the core) without defeating the purpose of the present invention, generally GeO2 is not positively added to the clad.
llZ~;5~8 1 If the coefficient of thermal expansion of the core 1 is substantially different than that of the clad 2, extremely large stress is generated between the core 1 and the clad 2, which can cause the composite member to split. In order to avoid this problem, the coefficient of thermal expansion is controlled by adding additives such as P2O5 and B2O3 to the core 1 which do not largely affect the refractive index of the core by comparison to the employment of GeO2 alone, but do reduce the softening temperature of the core. The addition of these additives is generally controlled such that the soften-ing temperature of the core is about 50 to 200 C lower than the clad and the coefficient of thermal expansion differential is 3 x 10 7~oC or less. The exact amounts added depend on several factors including the diameter of the preform and the perform and the type of optical fiber. Additives such as GeO2 and B2O3 are used in the present invention because they are accompanied by a minimum of light energy absorption and scattering.
Since scattering loss increases in proportion to the amount of the additives, the amount of additives such as GeO2, P2O5 and B2O3 in the core must be small in order to reduce scattering loss. On the other hand, the refractive index of the core should be increased in order to reduce microbending loss and emission loss. For this purpose the amount of addi-tives, in particular GeO2 should be increased.
Furthermore it is known that in an optical fiber the distribution of the refractive index of the core 1 varies across the diameter in the form of a parabola as shown in Fig.
2, and the transmission band (width) of the optical fiber is inversely proportional to the second power of the difference ~1.'Z65~3 1 (An) between the maximum va]ue of the refractive index of the core and the refractive index of the clad. In view of this, ~n should be small in order to broaden the transmission band and, thus, the amount of GeO2 should be maintained low. Thus, there is the dilemma that high amounts o-E GeO2 are required in the core in order to increase its refractive index and reduce transmission loss but if too high an amount of GeO2 is present in the core an increases which leads to a narrower transmission band width.
As can be understood from the foregoing, the amount of the additives in an optical fiber having low transmission loss and a broad transmission band must be balanced and confinecl to certain ranges.
One example of a method of producing a preform for optical fibers by a flame hydrolyzing process is described below.
This manufacturing method is shown schematically in Fig. 3. From a first nozzle 3 and a second nozzle 4, a gaseous glass-forming material containing additives providing a higher refractive index than SiO2 (for example, a mixture of SiC14, GeC14, PoC13, and ~Br3) and a gaseous glass-forming material containing additives providing a lower refractive index than SiO2 (for example, a mixture of SiC14 and BBr3) are blown to-yether with a heat combustion gas (for example, oxygen and hydro-gen, butane and propane). The glass-forming material gasses are flame-hydrolyzed outside the multiple nozzles to forrn fine glass particles which accumulate on a starting rod 5. A fine glass particle body 6 is then grown in the axial direction. Tlle fine glass particle body gradually falls into a high temperature furnace having a temperature of 1400 to 1600 C whereby the glass particle body is sintered and vitrified thereby producing a 2654~3 1 preform for an optical glass fiber.
As shown in Fig. 2, the resulting preform for optical fibers has a refractive index distribution in the form of a parabola from the core 1.
The distribution of additives in a cross-section of a core glass is not uniform and the coefficient of thermal expansion also varies across the cross-section. If the co-efficient of thermal expansion varies greatly, stress occurs upon sintering the fine glass particle body 6 causing the fine glass particle body to crack. Furthermore, the preform tends to crack easily when the preform is removed from the high temp-erature furnace after the sintering, or at the time of preform-ing other heat-treatments.
In forming SiO2 glass containing GeO2 by flame-hydro-lyzed reaction, a noticeahle phenomena is recognized. That is, a solid solution is formed between GeO2 and SiO2, and a part of GeO2 i5 precipitated into crystals in the form of a hexagonal system. The hexagonal system GeO2 has a melting point of about 1086C which is much lower than the melting point of SiO2 (l6oooc to 1700C). Therefore, bubbles of vaporized GeO2 are apt to be formed by thermal treatment during draw forming operation of such core materials to obtain glass fibers. If such bubbles are generated transmission loss becomes large. The probahility of generation of bubbles ls large at higher con-centrations of GeO2- Various experiments have shown GeO2 amount should be less than 15 wt~, by which the generation of bubbles is negligible and low transmission loss is obtained.
Furthermore, if the central portion of the fine glass particle body 6 has a higher melting point than that of the outcr peripheral portion tllereof, sintering of the glass 1~ti5~
1 particle body will begin vitrification at the surface of the body making it difficult to drive off bubbles in the central portion completely. Hence bubbles tend to remain in the central portion and cause scattering loss in the optical fibers. To prevent these bubbles from forming, glass particle body 6 is produced by varying the amount of additives at the central portion and the peripheral portion within the above range, and sinter~d.
As will be understood from the above, the amounts of additives in the core portions of the preform for optical fibers are limited to certain ranges. When a fine glass particle body 6 containing 5 to 15% by weight of GeO2 at the core and contain-ing O to 10% by weight P205 and B203 was sintered, a very good preform for optical fibers was obtained. Furthermore, a good preform for optical fibers was obtained from glass particle body 6 containing 15% by weight or more in total of GeO2, l'25 and ~23 at the core. By adjusting the amount of GeO2 to adjust Qn (in this field to about 0.9 to 1.2%)(which is closely related to the transmission loss and the transmission band) to less than ~ 15% by weight, a preform foroptical fibers having high quali-ty with a transmission loss of not more than 3.0ds/km (at 0.85 micromèter) and a transmission band of at least 40~Hz km0~75 (0.75th power) was obtained.
In the above experiments, GeO2, P205 and B203 ~e~e used as additives for the clad glass. The amounts of the addj-tives in the clad glass should be properly adjusted depending upon the composition of the core portion. These additives are not restricted to GeO2, P205 and B203 as it will be recognized from the foregoing that other additives permitting low loss and low scattering which can control the rcfractive index, the ;S48 1 coefficient of thermal expansion and the meltiny point, such as TiO2~ ~1203, SiF4 and Ga203 can also be used. Furthermore, the clad may be pure quartz glass consistiny of SiO2-While the above description has been directed tograded index optical fibers in which the refractive index of the core varies in the form of a parabola as shown in Figure 2, the above experimental facts are also applicable to optical fibers.
The following Examples illustrate the present inven-tion in more detail. Unless otherwise indicated all percentagesare by weight.
COMPARATIVE E ~ IPLE 1 Amount of base material SiO2 86.70%
Amount of additives for the core glass:
GeO2 12%
P205 0-3%
B203 1~6 , Total 13.3%
Amount of base material SiO2 95%
Amount of an additive for the clad glass:
B2 3 5%
A fine glass particle body having the above composition was produced and sintered. Cracks occurred in the clad glass.
Amount of base material SiO2 88.89 Amount of additives at the core glass:
G~02 8.2%
P205 0.51%
S4t~
1Comparative Example 2 continued l323 2.4%
Total 11.11%
Amount of base material SiO2 92%
Amount of an additive for the clad glass:
B2O3 8%
A fine glass particle body having the above composi-tion was produced and sintered in a high temperature furnace at 1550 C. A porous portion remained in the core portion and a completely solid preform for optica] fibers could not be obtain-ed.
EXAr~PLE 1 Amount of base material SiO2 79.27%
Amount of additives for the core glass:
GeO2 13.8%
P205 0.53%
B203 6.4%
Total 20.73%
Amount of base material SiO2 93.42%
Amount of additlves for the clad glass:
GeO2 3.5%
P2P5 0.28%
~23 2.8%
Total 6.58%
A fine glass body having the above composition was produced and sintered in a furnace at 1500C. A ~ood preform for optical fibers was obtained. The preform was spun in~o a fiber having an outer diameter of 150 microns. The transmission loss and the transmission band of the fib~r per kilometer ~rere --8~
~ `` liZ~;5~8 1 4.5dB/km (loss at 0.~3 micrometer) and 225L~Z-km, respectively.
E~AMPLE 2 Amount of base material sio2 81.72 Amount of additives for the core glass:
GeO2 12.5%
P2O5 0.48%
23 5.3%
Total 18.28%
Amount of base material SiO2 90.02%
Amount of additives for the clad glass:
GeO2 3.2~
P2O5 0.38%
B2O3 6.4%
Total 9.98%
A fine glass particle body having the above composi-tion was produced and sintered in a furnace at 1550C. ~ good preform for optical fibers was obtained. The preform was stretched to have a diameter of lOmm, and inserted into a ~0 quartz pipe having an inner diameter of llmm and an outer dia-meter of 20mm. The two were fused with each other and spun into a fiber haviny an outer diameter of 150 micrometers. The transmission loss and the transmission band of this fiber were 2.64dB/km (loss at 0.83 micrometer) and 405MHz-km (0.75 power:
coefficient for distance conversion), respectively.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and
3~ modifications can be made therein without departiny from the spirit and scope thereof.
Claims (5)
1. An optical fiber comprising a clad glass comprising mainly quartz glass and a core glass comprising mainly quartz glass having a higher refractive index than the clad glass, wherein said core glass is a quartz glass containing GeO2 and at least one dopant selected from the group consisting of P2O5, B2O3, TiO2, Al2O3, SiF4 and Ga2O3, the amount of GeO2 in the core glass being less than about 15% by weight and the total amount of GeO2 and the other dopants being about 15% by weight or more.
2. The optical fiber of Claim 1, wherein said quartz glass contains GeO2 and at least one of P2O5 and B2O3.
3. The optical fiber of Claim 1, wherein said clad glass consists of SiO2.
4. The optical fiber of Claim 1, wherein said clad glass is a mixture of SiO2 and at least one of GeO2, P2O5 and B2O3.
5. The optical fiber of Claim 1, wherein the amount of GeO2 in the core glass is greater than about 5% by weight and less than about 15% by weight.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9382478A JPS5521059A (en) | 1978-07-31 | 1978-07-31 | Optical fiber |
| JP93824/78 | 1978-07-31 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1126548A true CA1126548A (en) | 1982-06-29 |
Family
ID=14093138
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA332,751A Expired CA1126548A (en) | 1978-07-31 | 1979-07-27 | Optical fiber composition |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS5521059A (en) |
| CA (1) | CA1126548A (en) |
| DE (1) | DE2930816C2 (en) |
| FR (1) | FR2433493A1 (en) |
| GB (1) | GB2029400B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3031147A1 (en) * | 1980-08-18 | 1982-03-18 | Siemens AG, 1000 Berlin und 8000 München | METHOD FOR PRODUCING GLASS WITH A PRE-DETERMINED REFRIGERATION PROFILE AND ALKALINE-FREE GLASS FROM AN OXIS OF A BASE MATERIAL DOPED WITH ONE OR SEVERAL SUBSTANCES |
| US4439007A (en) * | 1981-06-09 | 1984-03-27 | Bell Telephone Laboratories, Incorporated | Low dispersion single mode fiber |
| US4629485A (en) * | 1983-09-26 | 1986-12-16 | Corning Glass Works | Method of making fluorine doped optical preform and fiber and resultant articles |
| DE3402318A1 (en) * | 1984-01-24 | 1985-07-25 | Wacker-Chemitronic Gesellschaft für Elektronik-Grundstoffe mbH, 8263 Burghausen | METHOD FOR DOPING LIGHT WAVE BASE MATERIAL ON QUARTZ GLASS BASE WITH GERMANIUM |
| US4669821A (en) * | 1984-09-19 | 1987-06-02 | Hughes Aircraft Company | Radiation resistant optical fiber waveguide |
| US4620861A (en) * | 1985-11-04 | 1986-11-04 | Corning Glass Works | Method for making index-profiled optical device |
| KR900003449B1 (en) * | 1986-06-11 | 1990-05-19 | 스미도모덴기고오교오 가부시기가이샤 | Dispersion-shift fiber and its production |
| DE4242546A1 (en) * | 1992-12-16 | 1994-06-23 | Richter Thomas | Technical glasses in auto-radial combination for determining physical dimensions |
| EP0849231B1 (en) * | 1996-12-20 | 2004-05-06 | Corning Incorporated | Athermalized codoped optical waveguide device |
| RU2156485C1 (en) * | 1999-05-19 | 2000-09-20 | Научный центр волоконной оптики при Институте общей физики РАН | Photosensitive fibre-optic light conduit and photoinduced structure |
| DE102009015076A1 (en) * | 2009-03-31 | 2010-10-14 | Heraeus Quarzglas Gmbh & Co. Kg | Doped quartz glass optical filter material for use with a UV lamp |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1391177A (en) * | 1971-08-09 | 1975-04-16 | Thermal Syndicate Ltd | Vitreous siliceous material |
| US3884550A (en) * | 1973-01-04 | 1975-05-20 | Corning Glass Works | Germania containing optical waveguide |
| CA1034818A (en) * | 1975-04-16 | 1978-07-18 | Northern Electric Company Limited | Manufacture of optical fibres |
| JPS51121016A (en) * | 1975-04-16 | 1976-10-22 | Fujitsu Ltd | Glass for optical transmitter |
| DE2538313C3 (en) * | 1975-08-28 | 1981-11-05 | Heraeus Quarzschmelze Gmbh, 6450 Hanau | Process for the production of a preliminary product for the production of an optical, self-focusing light guide |
| US4339173A (en) * | 1975-09-08 | 1982-07-13 | Corning Glass Works | Optical waveguide containing P2 O5 and GeO2 |
| JPS5288349A (en) * | 1976-01-20 | 1977-07-23 | Nippon Selfoc Co Ltd | Optical fiber for communication |
| JPS52121341A (en) * | 1976-04-06 | 1977-10-12 | Nippon Telegr & Teleph Corp <Ntt> | Production of optical fiber base materials and production apparatus fo r the same |
-
1978
- 1978-07-31 JP JP9382478A patent/JPS5521059A/en active Granted
-
1979
- 1979-07-26 GB GB7926144A patent/GB2029400B/en not_active Expired
- 1979-07-27 CA CA332,751A patent/CA1126548A/en not_active Expired
- 1979-07-30 DE DE19792930816 patent/DE2930816C2/en not_active Expired
- 1979-07-31 FR FR7919717A patent/FR2433493A1/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| FR2433493A1 (en) | 1980-03-14 |
| DE2930816C2 (en) | 1982-10-07 |
| GB2029400A (en) | 1980-03-19 |
| JPS5761699B2 (en) | 1982-12-25 |
| FR2433493B1 (en) | 1983-04-22 |
| DE2930816A1 (en) | 1980-03-13 |
| GB2029400B (en) | 1982-12-01 |
| JPS5521059A (en) | 1980-02-14 |
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