CN212770473U - High-speed deposition device for carrying out outer cladding on loose body of optical fiber preform - Google Patents

High-speed deposition device for carrying out outer cladding on loose body of optical fiber preform Download PDF

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Publication number
CN212770473U
CN212770473U CN202020661039.9U CN202020661039U CN212770473U CN 212770473 U CN212770473 U CN 212770473U CN 202020661039 U CN202020661039 U CN 202020661039U CN 212770473 U CN212770473 U CN 212770473U
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core rod
pipelines
ovd
groups
cavity
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CN202020661039.9U
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Chinese (zh)
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沈小平
杨志杰
戴杰
郭圣峰
朱坤
盖世佳
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Tongding Interconnection Information Co Ltd
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Tongding Interconnection Information Co Ltd
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Abstract

The utility model provides a high-speed deposition device for cladding loose bodies of optical fiber preforms, which comprises two groups of OVD blowlamps, a clamp, a servo motor, a pressure sensor and a waste gas outlet; the core rod is arranged at the central position in the cavity, two ends of the core rod are connected with the side wall of the cavity through clamps, and the end part of the core rod is provided with a servo motor; two groups of OVD blowlamps are arranged on one side of the core rod and are arranged around the circumference of the core rod; a plurality of waste gas outlets are formed in the upper part of the cavity, and reaction gas generated in the cavity is discharged from the waste gas outlets; and a pressure sensor is arranged on the outer side wall of the cavity at one side of the waste gas outlet. The utility model discloses can be fast, the even, the jumbo size optical fiber perform of high-efficient preparation external diameter, utilize the optical fiber perform of the preparation of the blowtorch of the invention, so the blowtorch need not be removed in the length of blowtorch exactly the length of perform, reduced because the both ends that the round trip movement blowtorch brought are scrapped, the cross design of raw materials pipeline has compensatied the inhomogeneous defect of external diameter simultaneously.

Description

High-speed deposition device for carrying out outer cladding on loose body of optical fiber preform
Technical Field
The utility model relates to an optical fiber manufacturing field, concretely relates to loose body of optical fiber perform carries out high-speed deposition apparatus of surrounding layer.
Background
With the rapid development of optical communication, the competition of the optical fiber market at home and abroad is more and more tragic, the manufacturing cost of the optical fiber is reduced, the product quality is improved, and the manufacture of large-size optical fiber preforms is a necessary way of the optical fiber industry in China. In the aspect of reducing the manufacturing cost of the optical fiber, on one hand, the rejection rate of various working procedures such as a core rod, stretching, outsourcing and the like in the manufacturing process of the optical fiber is reduced, and on the other hand, the improvement of the process for reducing the content of He, the improvement of the production efficiency, the improvement of the utilization rate of silicon tetrachloride and the like are realized. Mainstream preparation technologies of the optical fiber preform include a PCVD (plasma chemical vapor deposition) method, an MCVD (metal chemical vapor deposition) method, an OVD (over-voltage chemical vapor deposition) method, a VAD method and an APVD method, the VAD method is combined with an OVD (over-voltage chemical vapor deposition) total synthesis process to prepare the optical fiber preform, and a great space is provided for an outer cladding layer preparation process in order to reduce the manufacturing cost of the optical fiber. The OVD method is developed by Corning corporation for preparing a preform core rod, and is also widely applied to preparing an outer cladding layer through scientific and technological development, and the chemical reaction mechanism is a flame hydrolysis process, namely a gaseous halide (SiCl)4Etc.) react by oxyhydrogen flame or methane flame to produce a large amount of nanometer white SOOT powder, gradually deposit a layer of powder on the core rod along with the reciprocating movement of the rod body along the blowtorch until the powder becomes a preform loose body with preset size and shape, and the loose body after deposition is degassed and sintered in a high-temperature sintering furnace to finally obtain a transparent glass preform. The OVD method has the advantages of high deposition rate, high deposition efficiency, simple process and the like, and becomes the mainstream direction for preparing large-size optical fiber preforms.
The productivity of the optical fiber preform of the equipment is improved, and the deposition rate is mainly improved. In the prior art, a row of blowlamps with equal intervals are vertically arranged on one side of a redeposition cavity, although the deposition rate of OVD outsourcing can be obviously improved, the defects of uneven outer diameter, low deposition efficiency, uneven SOOT rod density, easy cracking and the like can be caused by simply increasing the number of the blowlamps.
Disclosure of Invention
The utility model aims to provide a to the shortcoming such as inhomogeneous, the deposition efficiency low of the external diameter that exists in the current preparation process, the inhomogeneous easy fracture of SOOT stick density, provide a high-speed deposition device who carries out the surrounding layer to the loose body of optical fiber perform.
In order to achieve the above purpose, the utility model provides a technical scheme is:
a high-speed deposition device for carrying out outer cladding on a loose body of an optical fiber preform comprises a cavity, a core rod, two groups of OVD torches, a clamp, a servo motor, a pressure sensor and a waste gas outlet; the core rod is arranged at the central position in the cavity, two ends of the core rod are connected with the side wall of the cavity through clamps, a servo motor is arranged at the end part of the core rod, and an output shaft of the servo motor is connected with the core rod and used for driving the core rod to rotate in the cavity; two groups of OVD blowlamps are arranged on one side of the core rod and distributed around the circumference of the core rod, a gap is reserved between the OVD blowlamps and the surface of the core rod, nozzles of the two groups of OVD blowlamps face the surface of the core rod, and when the core rod rotates, the two groups of OVD blowlamps carry out particle deposition on the surface of the core rod; a plurality of waste gas outlets are formed in the upper part of the cavity, and reaction gas generated in the cavity is discharged from the waste gas outlets; and a pressure sensor is arranged on the outer side wall of the cavity at one side of the waste gas outlet.
In order to optimize the technical scheme, the specific measures adopted further comprise:
the OVD blowtorch comprises a plurality of groups of raw material pipelines, a plurality of groups of inert gas pipelines, a plurality of groups of combustible gas pipelines and a plurality of groups of oxidant pipelines which are arranged in parallel, wherein the gas outlets of the inert gas pipelines, the combustible gas pipelines and the oxidant pipelines are deviated to the gas outlet of the raw material pipelines; the multiple groups of raw material pipelines are arranged at the central position of the OVD blowtorch and are arranged in a staggered manner; inert gas pipelines are symmetrically arranged on two sides of the raw material pipeline, and the inert gas pipelines are arranged in parallel; the outer sides of the inert gas pipelines are provided with combustible gas pipelines which are arranged in parallel; oxidant pipelines are arranged on the outer sides of the combustible gas pipelines, and are arranged in parallel; the combustible gas pipelines and the oxidant pipelines are arranged in a staggered mode.
The raw material pipeline, the inert gas pipeline, the combustible gas pipeline and the oxidant pipeline are all provided with spherical buffer cavities.
The raw material pipeline is internally provided with mixed gas of silicon-based raw materials and oxygen; argon is arranged in the inert gas pipeline; hydrogen or methane is arranged in the combustible gas pipeline; and oxygen is arranged in the oxidant pipeline.
The setting angle between the two groups of OVD blowlamps is 30-35 degrees.
The OVD blowtorch is provided with a CCD camera for detecting the diameter of the core rod.
The core rod is also provided with a weight detector for detecting the weight of the core rod.
The length of the OVD blowtorch is consistent with the length of the core rod to be processed.
Compared with the prior art, the utility model the advantages of do:
1. the utility model discloses a set up the OVD outsourcing equipment of two sets of blowtorch, can be fast, the even, the jumbo size optical fiber perform of high-efficient preparation external diameter. The optical fiber preform rod prepared by the blowtorch has the advantages that the blowtorch does not need to be moved because the length of the blowtorch is the length of the preform rod, the scrappage of two ends caused by moving the blowtorch back and forth is reduced, meanwhile, the defect of uneven outer diameter is made up by the crossed design of the raw material pipelines, and the loose body of the large-size optical fiber preform rod can be quickly prepared by the design of the two groups of blowtorches.
2. The blowtorch design is banded blowtorch, and the equipment damage that reducible reciprocating motion brought has improved equipment stability, and the design of whole blowtorch face can improve deposition rate by a wide margin in addition, and the globular buffering of blowtorch gas circuit can let the process gas of each pipeline more even flame stability stronger.
3. The utility model discloses the design theory of two sets of blowtorch, the operation of deposit simultaneously further improves deposition rate by a wide margin, and 120 kg's the loose body of optical fiber perform only needs 10 hours can deposit and accomplish, has improved equipment productivity greatly.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention.
Fig. 2 is a top view of the OVD torch of the present invention.
Fig. 3 is a cross-sectional view of the OVD torch of the present invention.
Figure 4 is a graph of the bulk density of the optical fiber preform at different stages of deposition.
Fig. 5 is a schematic view of the torch flame for different process gas flows of the present invention.
Fig. 6 is a schematic view of the OVD torch and the position structure of the core rod of the present invention.
In the figure, the serial numbers are 1-cavity, 2-core rod, 3-OVD blowtorch, 4-clamp, 5-servo motor, 6-pressure sensor, 7-waste gas outlet, 8-CCD camera, 9-weight detector, 31-raw material pipeline, 32-inert gas pipeline, 33-combustible gas pipeline, 34-oxidant pipeline and 35-spherical buffer cavity.
Detailed Description
The present invention will be further explained with reference to the drawings and examples.
Referring to fig. 1, the high-speed deposition apparatus for overcladding a loose body of an optical fiber preform comprises a cavity 1 and a core rod 2, and further comprises two groups of OVD torches 3, a clamp 4, a servo motor 5, a pressure sensor 6 and an exhaust gas outlet 7; the core rod 2 is arranged at the central position in the cavity 1, two ends of the core rod 2 are connected with the side wall of the cavity 1 through clamps 4, a servo motor 5 is arranged at the end part of the core rod 2, and an output shaft of the servo motor 5 is connected with the core rod 2 and used for driving the core rod 2 to rotate in the cavity 1; two groups of OVD torches 3 are arranged on one side of the core rod 2, the two groups of OVD torches 3 are arranged around the circumferential direction of the core rod 2, specifically, referring to the arrangement of FIG. 6, a gap is left between the OVD torches 3 and the surface of the core rod 2 and is used for performing jet deposition on the surface of the core rod, nozzles of the two groups of OVD torches 3 face the surface of the core rod 2, and when the core rod 2 rotates, the two groups of OVD torches 3 perform particle deposition on the surface of the core rod 2; a plurality of waste gas outlets 7 are formed in the upper part of the cavity 1, reaction gas generated in the cavity 1 is discharged from the waste gas outlets 7, and the pressure in the cavity can be controlled by controlling the closing of the waste gas outlets; the outer side wall of the cavity 1 at one side of the waste gas outlet 7 is provided with a pressure sensor 6 for detecting and controlling the pressure in the cavity, and preferably, the pressure sensor is PT124G-111 type.
Referring to fig. 2 and 3, the OVD torch 3 includes a plurality of sets of raw material pipelines 31, a plurality of sets of inert gas pipelines 32, a plurality of sets of combustible gas pipelines 33, and a plurality of sets of oxidant pipelines 34, which are arranged in parallel, wherein the gas outlets of the inert gas pipelines 32, the combustible gas pipelines 33, and the oxidant pipelines 34 are offset to the gas outlet of the raw material pipelines 31; a nozzle is arranged at the air outlet of each pipeline, and the diameter of each nozzle can be 2-8 mm; wherein, the plurality of groups of raw material pipelines 31 are arranged at the central position of the OVD blowtorch 3, and the raw material pipelines 31 are arranged in a staggered way; inert gas pipelines 32 are symmetrically arranged on two sides of the raw material pipeline 31, and the inert gas pipelines 32 are arranged in parallel; the outside of the inert gas pipeline 32 is provided with a combustible gas pipeline 33, and the combustible gas pipelines 33 are arranged in parallel; oxidant pipelines 34 are arranged outside the combustible gas pipelines 33, and the oxidant pipelines 34 are arranged in parallel; the flammable gas pipeline 33 and the oxidant pipeline 34 are arranged in a staggered manner.
In this embodiment, the raw material pipeline 31, the inert gas pipeline 32, the combustible gas pipeline 33, and the oxidant pipeline 34 are all provided with a spherical buffer chamber 35.
In this embodiment, a mixed gas of a silicon-based raw material and oxygen is disposed in the raw material pipeline 31; argon is arranged in the inert gas pipeline 32; hydrogen or methane is arranged in the combustible gas 33 pipeline; oxygen is provided in the oxidant line 34.
In this embodiment, the angle between the two sets of OVD torches 3 is 30 to 35 °.
In this embodiment, the OVD torch 3 is provided with a CCD camera 8 for detecting the diameter of the mandrel, and the CCD camera 8 is used for detecting the diameter of the mandrel in real time and moving up and down in the target length direction to measure the target mandrel.
In this embodiment, the core rod 2 is further provided with a weight detector 9 for detecting the weight of the core rod, and the overall average density of the silica loose body at different stages is further obtained by detecting the actual weight of each stage. The weight detector 9 adopts a model of TSC-06-BOOX, and can monitor and record the weight of the core rod in the deposition process in real time.
In this embodiment, the length of the OVD torch 3 is the same as the length of the mandrel 2 to be machined.
The utility model discloses a concrete use:
the specific preparation method of the loose body of the optical fiber preform comprises the following implementation steps:
the first step is as follows: the method comprises the steps of preparing a loose core rod body by VAD (vacuum axial deposition) or PCVD (plasma chemical vapor deposition) and other processes, then dehydrating and sintering in a high-temperature sintering furnace to obtain a transparent core rod, wherein the core rod has a certain core cladding proportion and a specific refractive index profile, and stretching to obtain the core rod with a target diameter.
The second step is that: after welding the upper and lower handles, pickling (HF + H in a certain proportion)2SO4Solution) or flame polishing, and removing impurities on the surface of the core rod.
The third step: installed in the device of the utility model for outer cladding layer deposition.
Silicon tetrachloride is used as a main deposition raw material, hydrogen is used as fuel gas, oxygen is used as oxidant gas, argon is used as inert protective gas, the raw material gas and the process gases are sprayed out from two groups of OVD torches, and silicon dioxide particles are produced through high-temperature hydrolysis reaction and deposited on a target core rod. As mentioned above, the deposition is carried out by one group of torches at the beginning, and when the diameter of the core rod reaches 50-80 mm, two groups of OVD torches work simultaneously, so that the deposition rate is greatly improved. The relative pressure difference that exhaust outlet can control the cavity is 300 ~ 900pa, specifically can detect through pressure sensor. When the core rod is driven by a servo motor to rotate, the rotating speed is 65-85 r/min from 150r/min when deposition starts to 65-85 r/min when deposition ends, silicon tetrachloride is not introduced before deposition starts, flame polishing is carried out on the surface of the core rod by oxyhydrogen flame, the cleanliness of the surface of the core rod and preheating of the core rod are further improved, then deposition is carried out according to a deposition formula, the flow rate of the silicon tetrachloride is 0.8 l/min from the beginning to 10 l/min when deposition ends, other process gases are changed simultaneously according to the formula, and as two groups of blowlamps are adopted for simultaneous deposition in the embodiment, the deposition of a 120kg optical fiber preform loose body needs about 9-10 hours, the outer diameter is 350mm, and the density is about 0.55 g/min.
Reference is made to FIG. 4, which shows the mean density over the bulk of the silica deposited according to the example at different stages, where the ordinate is the unit of density in g/cm3The abscissa represents 1-12 deposition stages, and obviously shows that the density is low from inside to outside, and the density difference is small, so that the cracking is not easy to occur in the transportation and sintering processes, and the manufacturing yield is improved.
Referring to fig. 5, the diameters of the prepared core rods are different, generally from 30 mm to 50mm, and the core rods with different diameters need to be matched with different deposition formulas. In this example, the flame conditions at different flow rates were verified to match different mandrels. The ordinate is the flame height, the highest effective flame height is about 680mm, and the abscissa is the combined process gas flow, it being clear that the effective flame height decreases with increasing flow, but the silicon tetrachloride injected increases. The flame can be divided into a turbulent flame part and a laminar flame part, the laminar flame part obviously has stable flame, the flame of the turbulent flame part starts to shake and delaminate, for example, silica particles can not be uniformly distributed on an effective spraying area, so that the density of a silica layer deposited on the surface of a core rod is uneven, and because the flame temperature of the turbulent layer is higher and the agglomeration phenomenon of the silica particles is obvious, protrusions are easily aggregated on the surface of the core rod, so that the appearance of an optical fiber preform is influenced due to difficult sintering and transparency. The laminar flame within the demarcation point is generally selected to be directed to the surface of the core rod.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, many modifications and improvements can be made without departing from the inventive concept, and all of them belong to the protection scope of the present invention.

Claims (8)

1. The utility model provides a high-speed deposition apparatus of going on surrounding cladding to optical fiber perform loose body, includes cavity (1) and plug (2), its characterized in that: the device also comprises two groups of OVD blowlamps (3), a clamp (4), a servo motor (5), a pressure sensor (6) and a waste gas outlet (7); the core rod (2) is arranged at the central position in the cavity (1), two ends of the core rod (2) are connected with the side wall of the cavity (1) through clamps (4), a servo motor (5) is arranged at the end part of the core rod (2), and an output shaft of the servo motor (5) is connected with the core rod (2) and used for driving the core rod (2) to rotate in the cavity (1); two groups of OVD blowlamps (3) are arranged on one side of the core rod (2), the two groups of OVD blowlamps (3) are arranged around the circumference of the core rod (2), a gap is reserved between the OVD blowlamps (3) and the surface of the core rod (2), the nozzles of the two groups of OVD blowlamps (3) face the surface of the core rod (2), and when the core rod (2) rotates, the two groups of OVD blowlamps (3) carry out particle deposition on the surface of the core rod (2); a plurality of waste gas outlets (7) are formed in the upper part of the cavity (1), and reaction gas generated in the cavity (1) is discharged from the waste gas outlets (7); and a pressure sensor (6) is arranged on the outer side wall of the cavity (1) on one side of the waste gas outlet (7).
2. The apparatus of claim 1, wherein the apparatus for overcladding a soot preform comprises: the OVD blowtorch (3) comprises a plurality of groups of raw material pipelines (31), a plurality of groups of inert gas pipelines (32), a plurality of groups of combustible gas pipelines (33) and a plurality of groups of oxidant pipelines (34) which are arranged in parallel, wherein the gas outlets of the inert gas pipelines (32), the combustible gas pipelines (33) and the oxidant pipelines (34) are deviated to the gas outlet of the raw material pipelines (31); wherein, the plurality of groups of raw material pipelines (31) are arranged at the central position of the OVD blowtorch (3), and the raw material pipelines (31) are arranged in a staggered way; inert gas pipelines (32) are symmetrically arranged on two sides of the raw material pipeline (31), and the inert gas pipelines (32) are arranged in parallel; combustible gas pipelines (33) are arranged outside the inert gas pipelines (32), and the combustible gas pipelines (33) are arranged in parallel; oxidant pipelines (34) are arranged on the outer sides of the combustible gas pipelines (33), and the oxidant pipelines (34) are arranged in parallel; the combustible gas pipelines (33) and the oxidant pipelines (34) are arranged in a staggered mode.
3. The apparatus of claim 2, wherein the apparatus for overcladding a soot preform comprises: the raw material pipeline (31), the inert gas pipeline (32), the combustible gas pipeline (33) and the oxidant pipeline (34) are all provided with spherical buffer cavities (35).
4. The apparatus of claim 2, wherein the apparatus for overcladding a soot preform comprises: the raw material pipeline (31) is internally provided with mixed gas of silicon-based raw materials and oxygen; argon is arranged in the inert gas pipeline (32); hydrogen or methane is arranged in the combustible gas pipeline (33); oxygen is arranged in the oxidant pipeline (34).
5. The apparatus of claim 1, wherein the apparatus for overcladding a soot preform comprises: the setting angle between the two groups of OVD blowtorch (3) is 30-35 degrees.
6. The apparatus of claim 1, wherein the apparatus for overcladding a soot preform comprises: and a CCD camera (8) for detecting the diameter of the core rod is arranged on the OVD blowtorch (3).
7. The apparatus of claim 1, wherein the apparatus for overcladding a soot preform comprises: and the core rod (2) is also provided with a weight detector (9) for detecting the weight of the core rod.
8. The apparatus of claim 1, wherein the apparatus for overcladding a soot preform comprises: the length of the OVD blowtorch (3) is consistent with the length of the core rod (2) needing to be processed.
CN202020661039.9U 2020-04-27 2020-04-27 High-speed deposition device for carrying out outer cladding on loose body of optical fiber preform Expired - Fee Related CN212770473U (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111517633A (en) * 2020-04-27 2020-08-11 通鼎互联信息股份有限公司 High-speed deposition device for carrying out outer cladding on loose body of optical fiber preform

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111517633A (en) * 2020-04-27 2020-08-11 通鼎互联信息股份有限公司 High-speed deposition device for carrying out outer cladding on loose body of optical fiber preform
CN111517633B (en) * 2020-04-27 2024-07-23 通鼎互联信息股份有限公司 Use method of high-speed deposition device for overcladding loose body of optical fiber preform

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