Optical fiber manufacturing method, system, and optical fiber

Abstract

The application relates to the technical field of optical fiber manufacturing, aims to solve the technical problem that some known optical fibers are prone to unstable optical signal transmission in a working environment with a large temperature difference, and provides an optical fiber preparation method, system and optical fiber. The optical fiber preparation method comprises the following steps: coating a first coating on the outer circumferential surface of a fiber core, the glass transition temperature of the first coating being less than or equal to a first preset temperature, and the first preset temperature being less than 0 DEG C; coating a second coating on the outer circumferential surface of the first coating, the glass transition temperature of the second coating being greater than or equal to a second preset temperature, and the second preset temperature being greater than 0 DEG C; curing the first coating to form a first coating layer; curing the second coating to form a second coating layer, and manufacturing an optical fiber, the thermal weight loss of the second coating layer being less than or equal to 10% after being placed at a third preset temperature for a preset time, and the third preset temperature being greater than the second preset temperature. The application has the beneficial effect of improving the optical signal transmission stability of the optical fiber in a working environment with a large temperature difference.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of optical fiber manufacturing, in particular to an optical fiber preparation method, system and optical fiber. BACKGROUND

[0002] Known optical fibers can only work stably in a narrow temperature range, and in a working environment with a large temperature difference, the known optical fibers are prone to unstable optical signal transmission. SUMMARY

[0003] The present application provides an optical fiber preparation method, system and optical fiber to solve the technical problem that some known optical fibers are prone to unstable optical signal transmission in a working environment with a large temperature difference.

[0004] Embodiments of the present application are implemented as follows:

[0005] In a first aspect, the present application provides an optical fiber preparation method, comprising: coating a first coating on an outer circumferential surface of a fiber core, the glass transition temperature of the first coating being less than or equal to a first preset temperature, the first preset temperature being less than 0℃; coating a second coating on an outer circumferential surface of the first coating, the glass transition temperature of the second coating being greater than or equal to a second preset temperature, the second preset temperature being greater than 0℃; curing the first coating to form a first coating layer; curing the second coating to form a second coating layer, and manufacturing an optical fiber, the thermal weight loss of the second coating layer after being placed at a third preset temperature for a preset time being less than or equal to 10%, the third preset temperature being greater than the second preset temperature.

[0006] The glass transition temperature of the first coating layer is lower than the first preset temperature, and when the working environment temperature of the optical fiber is higher than the first preset temperature, the first coating layer can remain in a high-elasticity state. The hardness of the high-elasticity first coating layer is much lower than that of the glassy first coating layer, which can protect the fiber core and greatly reduce the risk of damage caused by the glassy first coating layer during the working process of the optical fiber. When the working environment temperature of the optical fiber is lower than the first preset temperature, the first coating layer has a glass transition zone in a temperature range lower than the first preset temperature, and in this temperature range, the first coating layer can still remain in a high-elasticity state, thereby also protecting the fiber core.

[0007] The glass transition temperature of the second coating layer is greater than the second preset temperature. When the working environment temperature of the optical fiber is lower than the second preset temperature, the second coating layer in the glass state can exert a compression force on the fiber core, and the first coating layer can effectively reduce the compression force to ensure the protection effect on the fiber core. When the working environment temperature of the optical fiber is higher than the second preset temperature, the second coating layer is in a high-elastic state, and the compression force exerted by the second coating layer on the fiber core is greatly reduced. Since the thermal weight loss of the second coating layer is less than or equal to 10% after being placed at the third preset temperature for a preset time, when the working environment temperature of the optical fiber is higher than the third preset temperature, the thermal weight loss of the second coating layer is not obvious, thereby protecting the first coating layer and the fiber core from carbonization in a high-temperature environment.

[0008] Therefore, the lower limit of the working temperature range of the optical fiber prepared by the optical fiber preparation method according to the present application can be slightly lower than the first preset temperature, and the upper limit can be set between the second preset temperature and the third preset temperature. The first preset temperature is lower than 0℃, and the third preset temperature is higher than 0℃, so that the fiber core of the optical fiber can still be reliably protected by the first coating layer and the second coating layer in a working environment with a large temperature difference, and the optical fiber can stably transmit optical signals, thereby ensuring the working reliability of the optical fiber.

[0009] In a possible implementation manner,

[0010] The first preset temperature is less than or equal to -60℃.

[0011] In a possible implementation manner,

[0012] The material of the first coating material includes a modified acrylic resin and a first modifier, the content of the first modifier is 8% to 12%, and the first modifier includes hydroxyethyl acrylate, hexafluorobutyl acrylate, and trifluoroethyl methacrylate.

[0013] In a possible implementation manner,

[0014] The second preset temperature is greater than or equal to 60℃, the third preset temperature is not less than 180℃, and the preset time is not less than 36 hours.

[0015] In a possible implementation manner,

[0016] The material of the second coating material includes a modified acrylic resin and a second modifier, the content of the second modifier is 4% to 8%, and the second modifier includes an organic silicon modified epoxy acrylic resin with a content of 2.5% to 6.5%, a propoxylated glycerol triacrylate with a content of 0.5% to 2%, an organic silicon adhesion promoter with a content of 0.1% to 0.35%, a first photoinitiator with a content of 0.1% to 1%, and a second photoinitiator with a content of 0.1% to 0.5%.

[0017] In a possible implementation manner,

[0018] The curing the first coating and the second coating comprises: placing the fiber core coated with the first coating and the second coating in a protective gas environment with an oxygen content of ≤50 ppm for 0.001 s to 0.02 s, and irradiating the first coating and / or the second coating by a light source to cure the first coating and the second coating, the light source has a central wavelength of 210 nm to 500 nm, and the light source has a maximum power concentration area of an irradiation area of ≤0.18 cm 2 .

[0019] In a possible implementation manner,

[0020] The first coating has a first relative curing degree relative to the fiber core, the first relative curing degree is 86% to 96%; the second coating has a second relative curing degree relative to the fiber core, the second relative curing degree is 90% to 100%, and the second relative curing degree is greater than the first relative curing degree.

[0021] In a possible implementation manner,

[0022] After the optical fiber is manufactured, the optical fiber is subjected to high-low temperature cycle treatment in a temperature environment of -80°C to 200°C, and a change in attenuation of the optical fiber is monitored; the high-low temperature cycle treatment comprises multiple temperature cycles, each of the temperature cycles comprises: maintaining the temperature of the optical fiber in a first temperature range for a first preset time length, adjusting the temperature of the optical fiber from the first temperature range to a second temperature range within a second preset time length, maintaining the optical fiber in the second temperature range for a third preset time length, and adjusting the temperature of the optical fiber from the second temperature range to the first temperature range within the second preset time length, the first temperature range and the second temperature range are non-overlapping, and one of the first temperature range and the second temperature range is in a range of -90°C to -40°C, and the other is in a range of 140°C to 210°C.

[0023] In a second aspect, the present application provides an optical fiber manufacturing system for performing the optical fiber manufacturing method described above, the optical fiber manufacturing system comprises: a coating device, the coating device is configured to coat a first coating on an outer circumferential surface of a fiber core, and to coat a second coating on an outer circumferential surface of the first coating; and a curing device, the curing device is configured to cure the first coating and the second coating, and to form a first coating layer and a second coating layer.

[0024] In a third aspect, the present application provides an optical fiber manufactured by the optical fiber manufacturing method described above, the optical fiber comprises: a fiber core; a first coating layer, the first coating layer is coated on an outer surface of the fiber core; and a second coating layer, the second coating layer is coated on an outer circumferential surface of the first coating layer. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings in the embodiments. It should be understood that the following drawings only show some of the embodiments of the present application, and therefore should not be considered as limiting the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0026] Figure 1 Flow chart of a fiber preparation method according to an embodiment of the present application;

[0027] Figure 2 Flow chart of a fiber preparation method according to an embodiment of the present application;

[0028] Figure 3 Change curve of the additional attenuation of a fiber according to an embodiment of the present application under high-low temperature cycle treatment;

[0029] Figure 4 Change curve of the additional attenuation of a fiber according to an embodiment of the present application under a constant temperature environment;

[0030] Figure 5 Structural schematic diagram of a fiber preparation system according to an embodiment of the present application;

[0031] Figure 6 Structural schematic diagram of a fiber according to an embodiment of the present application;

[0032] Figure 7 Schematic diagram of the outer diameter and relative refractive index difference of each layer of a fiber according to an embodiment of the present application.

[0033] Main element symbol explanation:

[0034] Optical fiber manufacturing system 100 Rod feeding device 10 Drawing device 20 Temperature maintaining device 30 First measuring device 40 Tension control device 50 Coating device 60 Curing device 70 Second measuring device 80 Winding device 90 Optical fiber 200 Core 201 Core layer 202 Inner cladding layer 203 Middle cladding layer 204 Outer cladding layer 205 First coating layer 206 Second coating layer 207 Preform rod 300 DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments.

[0036] It should be noted that when an element is referred to as being "fixed" to another element, it can be directly on the other element or there can be an intervening element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or there can be an intervening element. When an element is referred to as being "disposed" on another element, it can be directly disposed on the other element or there can be an intervening element. The terms "vertical", "horizontal", "left", "right", and similar expressions used herein are for illustrative purposes only.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0038] Some embodiments of the present application are described in detail. In the case of no conflict, the following embodiments and features in the embodiments can be combined with each other.

[0039] Embodiments

[0040] Reference Figure 1 The present embodiment provides a method for preparing an optical fiber, comprising:

[0041] coating a first coating material on the outer circumferential surface of the core 201 at a first coating temperature, the glass transition temperature of the first coating material being less than or equal to a first preset temperature, the first preset temperature being less than 0℃;

[0042] coating a second coating material on the outer circumferential surface of the first coating material at a second coating temperature, the glass transition temperature of the second coating material being greater than or equal to a second preset temperature, the second preset temperature being greater than 0℃;

[0043] curing the first coating material to form a first coating layer 206, the elastic modulus of the first coating layer 206 being less than or equal to 0.7Mpa;

[0044] curing the second coating material to form a second coating layer 207, and manufacturing the optical fiber 200, the elastic modulus of the second coating layer 207 being greater than or equal to 650Mpa, the thermal weight loss of the second coating layer 207 after being placed at a third preset temperature for a preset time being less than or equal to 10%, the third preset temperature being greater than the second preset temperature.

[0045] The glass transition temperature of the first coating layer 206 is lower than the first preset temperature. When the working environment temperature of the optical fiber 200 is higher than the first preset temperature, the first coating layer 206 can remain in a high-elastic state. The hardness of the high-elastic first coating layer 206 is much lower than that of the glassy first coating layer 206, and the first coating layer 206 can protect the core 201 and greatly reduce the risk of damage caused by the extrusion of the glassy first coating layer 206 during the working process of the optical fiber 200. When the working environment temperature of the optical fiber 200 is lower than the first preset temperature, the first coating layer 206 has a glass transition zone in a temperature range lower than the first preset temperature. In this temperature range, the first coating layer 206 can still remain in a high-elastic state, thereby also protecting the core 201.

[0046] The glass transition temperature of the second coating layer 207 is greater than the second preset temperature. When the working environment temperature of the optical fiber 200 is lower than the second preset temperature, the second coating layer 207 in the glass state can exert a compression force on the core 201, and the first coating layer 206 can effectively reduce the compression force and ensure the protection effect on the core 201. When the working environment temperature of the optical fiber 200 is higher than the second preset temperature, the second coating layer 207 is in a high-elastic state, and the compression force exerted by the second coating layer 207 on the core 201 is greatly reduced. Since the thermal weight loss of the second coating layer 207 after being placed at the third preset temperature for a preset time is less than or equal to 10%, when the working environment temperature of the optical fiber 200 is higher than the third preset temperature, the thermal weight loss of the second coating layer 207 is not obvious, so that most of the second coating layer 207 can still be maintained on the surface of the first coating layer 206, thereby avoiding carbonization of the first coating layer 206 in a high-temperature environment and protecting the first coating layer 206 and the core 201.

[0047] The first coating layer 206 can greatly reduce the compression force exerted by the second coating layer 207 in the glass state on the core 201, thereby improving the protection effect on the core 201.

[0048] Therefore, the working temperature range of the optical fiber 200 prepared by the optical fiber preparation method according to the embodiment can have a lower limit value slightly lower than the first preset temperature and an upper limit value between the second preset temperature and the third preset temperature, and the first preset temperature is lower than 0°C and the second preset temperature is higher than 0°C, so that the core 201 of the optical fiber 200 can still be reliably protected by the first coating layer 206 and the second coating layer 207 in a working environment with a large temperature difference, and the optical fiber 200 can stably transmit optical signals, thereby ensuring the working reliability of the optical fiber 200.

[0049] In the embodiment, the first coating temperature can be set to 32°C to 55°C, and in other embodiments, the first coating temperature can be adjusted according to the specific material of the first coating material.

[0050] The second coating temperature can be set to 25°C to 60°C, and in other embodiments, the second coating temperature can be adjusted according to the specific material of the second coating material.

[0051] In the embodiment, the first preset temperature is less than or equal to -60°C. In this way, the lower limit value of the working temperature range of the optical fiber 200 is at least lower than -60°C, thereby greatly improving the cold resistance performance of the optical fiber 200, so that the optical fiber 200 can ensure stable transmission of optical signals in a working environment with a large diurnal temperature difference.

[0052] In the embodiment, the material of the first coating includes modified acrylic resin and a first modifier, the content of the first modifier is 5% to 12%, and the first modifier includes hydroxyethyl acrylate, hexafluorobutyl acrylate, and trifluoroethyl methacrylate. In this way, the first coating layer 206 formed by curing the first coating has a glass transition temperature less than or equal to -60°C.

[0053] In the embodiment, the modified acrylic resin includes poly(methyl acrylate) or poly(ethyl acrylate).

[0054] Table 1 shows the material ratio of several first coatings and the glass transition temperature of the first coating layer 206 formed by the first coatings.

[0055] Table 1

[0056]

[0057] In the embodiment, the viscosity of the first coating at 25°C is (4000-6500) mPa·s, and the density is (0.95-1.2) g / cm3.

[0058] In the embodiment, the second preset temperature is greater than or equal to 60°C, the third preset temperature is not less than 180°C, and the preset time length is not less than 36 hours. In this way, the upper limit of the working temperature range of the optical fiber 200 can be set to between 60°C and 180°C, thereby greatly improving the heat resistance of the optical fiber 200, and ensuring stable transmission of optical signals of the optical fiber 200 in a working environment with large diurnal temperature difference.

[0059] In the embodiment, the material of the second coating includes modified acrylic resin and a second modifier, the content of the second modifier is 4% to 8%, and the second modifier includes organic silicon modified epoxy acrylate resin with a content of 2.5%-6.5%, propoxylated glyceryl triacrylate with a content of 0.5%-2%, an organic silicon adhesion promoter with a content of 0.1%-0.35%, a first photoinitiator with a content of 0.1%-1%, and a second photoinitiator with a content of 0.1%-0.5%. In this way, the second coating layer 207 formed by curing the second coating has a glass transition temperature greater than or equal to 60°C, and the thermal weight loss after being placed at the third preset temperature for the preset time length is less than or equal to 10%.

[0060] In the embodiment, the third preset temperature can be set to 200°C, and the preset time length can be set to 48 hours.

[0061] In the embodiment, the modified acrylic resin includes poly(methyl acrylate).

[0062] Table 2 shows the material ratio of several second coatings and the glass transition temperature of the second coating layer 207 formed by the second coatings and the thermal weight loss data thereof.

[0063] Table 2

[0064]

[0065]

[0066] In the embodiment, the curing of the first coating and the second coating comprises: placing the fiber core 201 coated with the first coating and the second coating in a protective gas environment with an oxygen content of ≦50ppm, maintaining for 0.001-0.02 seconds, and curing the first coating and the second coating by irradiating the first coating and / or the second coating with a light source, the center wavelength of the light source being 210-500nm, and the maximum power concentration area of the irradiation area of the light source being ≦0.18cm2.

[0067] The light source is an LED light source, and the first protective gas in the protective gas environment is one of nitrogen, hydrogen, helium, and argon.

[0068] In the embodiment, the curing of the first coating and the second coating can be performed in two ways. First, the first coating is cured to form the first coating layer 206, the second coating is coated on the surface of the first coating layer 206, and then the second coating is cured to form the second coating layer 207. Second, the first coating is coated on the surface of the fiber core 201, the second coating is coated on the surface of the first coating, and the second coating is irradiated with a light source to complete the curing of the second coating and the first coating at the same time.

[0069] In the embodiment, the first coating layer 206 has a first relative curing degree relative to the fiber core 201, and the first relative curing degree is 86%-96%. The second coating layer 207 has a second relative curing degree relative to the fiber core 201, and the second relative curing degree is 90%-100%, the second relative curing degree being greater than the first relative curing degree.

[0070] Referring to Figure 2 In the embodiment, after the optical fiber 200 is manufactured, the optical fiber 200 is subjected to high-low temperature cycle treatment in a temperature environment of-80℃ to 200℃, and the change in attenuation of the optical fiber 200 is monitored; the high-low temperature cycle treatment comprises multiple temperature cycles, and each temperature cycle comprises: maintaining the temperature of the optical fiber 200 in a first temperature range for a first preset time length, adjusting the temperature of the optical fiber 200 from the first temperature range to a second temperature range within a second preset time length, maintaining the optical fiber 200 in the second temperature range for a third preset time length, adjusting the temperature of the optical fiber 200 from the second temperature range to the first temperature range within the second preset time length, the first temperature range and the second temperature range do not overlap, and one of them is in the range of-90℃ to-40℃, and the other is in the range of 140℃ to 210℃.

[0071] Through the high-low temperature cycle treatment, the service life of the optical fiber 200 and the anti-attenuation characteristics of the fiber core 201 can be further prolonged. Moreover, during the high-low temperature cycle treatment, the first relative curing degree of the first coating layer 206 can be further increased to 100%.

[0072] In this embodiment, the first temperature range can be specifically set to -80°C to -50°C, and the second temperature range can be specifically set to 150°C to 200°C. The first preset time length can be set to 1 hour to 4 hours, for example, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours. The second preset time length is greater than or equal to 4 hours, for example, 4 hours, 4.5 hours, 5 hours, 5.5 hours, 6 hours, etc. The third preset time length can be set to 1 hour to 4 hours, for example, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours or 4 hours.

[0073] Specifically, referring to Figure 3 It can be seen that the 1310nm additional attenuation curve, the 1550nm additional attenuation curve and the 1625nm additional attenuation curve of the optical fiber 200 sample prepared in this embodiment during the high-low temperature cycle treatment process are all within the acceptable range, and the 1550nm band attenuation can be reduced to below 0.18dB / km, and the mode field diameter can reach 9.2μm, which has good compatibility with the conventional G.652 optical fiber 200. Referring to Table 3, the additional attenuation, mode field diameter and strength of the optical fiber 200 sample prepared in this embodiment are related parameters, which better reflect the performance parameters of the optical fiber 200 prepared according to this embodiment.

[0074] Table 3

[0075]

[0076] Referring to Figure 4 The 1310nm additional attenuation curve, the 1550nm additional attenuation curve and the 1625nm additional attenuation curve of the optical fiber 200 sample prepared in this embodiment under the 150°C environment are shown in the table, and the unit is hour, it can be seen that the optical fiber 200 sample still has reliable additional attenuation data when it is in the 150°C environment for a long time, which indicates that it has good optical transmission performance.

[0077] In the embodiment, the optical fiber preparation method further comprises, before the first coating is applied, preparing the preform 300 by an axial vapor deposition one-step forming method, the prepared preform 300 comprising the core layer 202, the inner cladding layer 203, the middle cladding layer 204 and the outer cladding layer 205, and then melting the preform 300 to stretch the core 201. The axial vapor deposition one-step forming method can reduce the stress difference between adjacent layers caused by changes in the preparation method, thereby improving the strength of the core 201 to ensure that the core 201 has low attenuation and bending resistance. The low attenuation can reduce the influence of the first coating 206 and the second coating 207 on the attenuation performance of the core 201, ensuring that the finally prepared optical fiber 200 has low attenuation performance. The bending resistance can greatly reduce the bending possibility when the core 201 is coated with the first coating and the second coating, ensuring the reliable strength and bending resistance of the core 201 under the coating treatment of the first coating and the second coating.

[0078] Referring to Figure 5 The embodiment also provides an optical fiber preparation system 100 for executing the optical fiber preparation method described above. The optical fiber preparation system 100 comprises a coating device 60 and a curing device 70. The coating device 60 is used to coat the first coating on the outer circumferential surface of the core 201, and is used to coat the second coating on the outer circumferential surface of the first coating. The curing device 70 is used to cure the first coating and the second coating, and forms the first coating layer 206 and the second coating layer 207.

[0079] Referring to Figure 5 In the embodiment, the optical fiber preparation system 100 further comprises a preform feeding device 10, a drawing device 20, a heat preservation device 30, a first measuring device 40, a tension control device 50, a second measuring device 80 and a winding device 90.

[0080] The preform feeding device 10, the drawing device 20, the heat preservation device 30, the first measuring device 40, the tension control device 50, the coating device 60, the curing device 70, the second measuring device 80 and the winding device 90 are sequentially and spacedly arranged along the conveying direction of the optical fiber 200.

[0081] The rod feeding device 10 is used to feed the preform rod 300 into the drawing device 20, the preform rod 300 is driven by the winding device 90 to pass through the drawing device 20, and is fused and stretched to form the core 201 in the drawing device 20. After passing through the heat preservation device 30, the core 201 passes through the first measuring device 40, which is used to detect the outer diameter of the core 201, and the core 201 with a qualified outer diameter is fed to the tension control device 50, which is used to adjust the tension of the stretched preform rod 300 to achieve the effect of adjusting the outer diameter of the core 201. The core 201 passes through the tension control device 50 in turn, and then passes through the coating device 60 and the curing device 70, and the optical fiber 200 is output from the curing device 70. The optical fiber 200 passes through the second measuring device 80, which is used to detect the outer diameter of the optical fiber 200. The winding device 90 is also used to wind the optical fiber 200 with a qualified outer diameter.

[0082] In the embodiment, the drawing device 20 can be an induction drawing furnace or a graphite drawing furnace. The temperature in the drawing device 20 is between 1800℃ and 2200℃. When the preform rod 300 is fused in the drawing device 20, the temperature in the drawing device 20 changes within ±2℃. The drawing device 20 is filled with a second protective gas to avoid the reaction of the preform rod 300 with oxygen. The second protective gas can be an inert gas, specifically one of argon or helium or a mixture of the two. The flow rate of the protective gas is between 10L / min and 50L / min. The oxygen content of the second protective gas is ≤100ppm, and the drawing speed of the core 201 is ≥50m / min.

[0083] The optical fiber 200 that has completed stretching, coating and curing is sent to a high-low temperature cycle treatment device for high-low temperature cycle treatment.

[0084] Referring to Figure 6 , the embodiment also provides an optical fiber 200 made by the optical fiber preparation method described above, which comprises a core 201, a first coating layer 206 and a second coating layer 207. The first coating layer 206 is coated on the outer surface of the core 201. The second coating layer 207 is coated on the outer circumferential surface of the first coating layer 206.

[0085] In the embodiment, referring to Figure 6 and Figure 7 , the core 201 comprises a core layer 202, an inner cladding layer 203, a middle cladding layer 204 and an outer cladding layer 205.

[0086] The relative refractive index difference Δn1 of the core layer 202 is 0.32% to 0.38%. The material of the core layer 202 comprises silicon dioxide doped with germanium dioxide. The outer diameter of the core layer 202 is r1, and 3.9um ≤ r1 ≤ 4.7um.

[0087] The inner cladding layer 203 is coated on the outer circumferential surface of the core layer 202, the relative refractive index difference Δn2 of the inner cladding layer 203 is 0, the material of the inner cladding layer 203 includes pure silicon, the outer diameter of the inner cladding layer 203 is r2, and 7um≤r2≤11.5um.

[0088] The middle cladding layer 204 is coated on the outer circumferential surface of the inner cladding layer 203, the relative refractive index difference Δn3 of the middle cladding layer 204 is -0.15% to -0.01%, the material of the middle cladding layer 204 includes fluorine-doped silicon, the outer diameter of the middle cladding layer 204 is r3, and 7.8um≤r3≤15um.

[0089] The outer cladding layer 205 is coated on the outer circumferential surface of the middle cladding layer 204, the relative refractive index difference Δn4 of the outer cladding layer 205 is 0, the material of the outer cladding layer 205 includes pure silicon, the outer diameter of the outer cladding layer 205 is r4, and 62um≤r4≤63um.

[0090] In the embodiment, the outer diameter of the first coating layer 206 is 175um to 200uum, and the outer diameter of the second coating layer 207 is 235um to 255um.

[0091] The above embodiments are only used to illustrate the technical solutions of the present application and are not limited. Although the present application has been described in detail with reference to the above preferred embodiments, it should be understood by those skilled in the art that the technical solutions of the present application can be modified or replaced without departing from the spirit and scope of the present application.

Claims

1. A method of optical fiber manufacture, characterized by, The method comprises: applying a first coating to the outer circumferential surface of the core, the first coating having a glass transition temperature less than or equal to a first preset temperature, the first preset temperature being less than 0°C; applying a second coating to the outer circumferential surface of the first coating, the second coating having a glass transition temperature greater than or equal to a second preset temperature, the second preset temperature being greater than 0°C; curing the first coating to form a first coating layer; curing the second coating to form a second coating layer, and producing an optical fiber, the second coating layer having a thermal weight loss of less than or equal to 10% after being placed at a third preset temperature for a preset time, the third preset temperature being greater than the second preset temperature.

2. The method according to claim 1, wherein: the first preset temperature is less than or equal to -60°C.

3. The method according to claim 2, wherein: the material of the first coating comprises a modified acrylic resin and a first modifier, the content of the first modifier being 8% to 12%, and the first modifier comprising hydroxyethyl acrylate, hexafluorobutyl acrylate, and trifluoroethyl methacrylate.

4. The method according to claim 1, wherein: the second preset temperature is greater than or equal to 60°C, the third preset temperature is not less than 180°C, and the preset time is not less than 36 hours.

5. The method according to claim 4, wherein: the material of the second coating comprises a modified acrylic resin and a second modifier, the content of the second modifier being 4% to 8%, and the second modifier comprising an organic silicon modified epoxy acrylate resin with a content of 2.5% to 6.5%, a propoxylated glycerol triacrylate with a content of 0.5% to 2%, an organic silicon adhesion promoter with a content of 0.1% to 0.35%, a first photoinitiator with a content of 0.1% to 1%, and a second photoinitiator with a content of 0.1% to 0.5%.

6. The method according to claim 1, wherein: the curing of the first coating and the second coating comprises: placing the core coated with the first coating and the second coating in a protective gas environment having an oxygen content of ≦50 ppm for 0.001 to 0.02 seconds, irradiating the first coating and / or the second coating with a light source having a center wavelength of 210 nm to 500 nm to cure the first coating and the second coating, the light source having a maximum power concentration area of the irradiation area of ≦0.18 cm 2 .

7. The method according to claim 1, wherein: the first coating layer has a first relative curing degree relative to the core, the first relative curing degree being 86% to 96%; the second coating layer has a second relative curing degree relative to the core, the second relative curing degree being 90% to 100%, and the second relative curing degree being greater than the first relative curing degree.

8. The method according to claim 1, wherein: after the optical fiber is produced, the optical fiber is subjected to high-low temperature cycle treatment in a temperature environment between -80°C and 200°C, and the change in attenuation of the optical fiber is monitored; the high-low temperature cycle treatment comprises multiple temperature cycles, and each temperature cycle comprises: maintaining the temperature of the optical fiber in a first temperature range for a first predetermined time period, adjusting the temperature of the optical fiber from the first temperature range to a second temperature range for a second predetermined time period, maintaining the optical fiber in the second temperature range for a third predetermined time period, adjusting the temperature of the optical fiber from the second temperature range to the first temperature range for the second predetermined time period, the first temperature range and the second temperature range being non-overlapping, and one of the first temperature range being in a range of -90℃ to -40℃ and the second temperature range being in a range of 140℃ to 210℃.

9. An optical fiber manufacturing system characterized by comprising: A fiber preparation system for performing the fiber preparation method according to any one of claims 1 to 8, wherein the fiber preparation system comprises: a coating device for coating a first coating material on an outer circumferential surface of the core and for coating a second coating material on an outer circumferential surface of the first coating material; a curing device for curing the first coating material and the second coating material and forming a first coating layer and a second coating layer.

10. An optical fiber, characterized by, A fiber prepared by the fiber preparation method according to any one of claims 1 to 8, comprising: a core; a first coating layer coated on an outer surface of the core; a second coating layer coated on an outer circumferential surface of the first coating layer.

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