Rotating polarization-maintaining fiber high-tension on-line drawing device, system, method and product

Abstract

The application discloses a kind of high tension online wire drawing device, system, method and product of rotating polarization maintaining optical fiber, and the coating resin in conical dish is formed into vortex by paddle, opposite circumferential friction force is applied to bare optical fiber passing through it with the direction of rotation, to overcome the torsion of rotating polarization maintaining optical fiber when drawing, so that rotating polarization maintaining optical fiber can be drawn under greater drawing tension, thereby solve the technical problems such as poor strength, short length, higher attenuation caused by rotating polarization maintaining optical fiber drawn under low tension.The system provided by the application uses the above device to replace the coating cup of the existing drawing tower, without the need to additionally increase the mechanism, and is suitable for modification on the existing rotary drawing system.The optical fiber prepared by using high tension drawing process has lower attenuation, higher strength, longer length, more accurate rotating pitch distribution, and better appearance consistency and environmental reliability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of optical fiber manufacturing, and more particularly, to a high-tension online drawing device, system, method and product for a rotary polarization-maintaining optical fiber. BACKGROUND

[0002] Rotary polarization-maintaining optical fiber is a special polarization-maintaining optical fiber, which introduces circular birefringence through the rotation of the optical fiber axis, and forms elliptical birefringence together with the high linear birefringence of the optical fiber itself. In the case of a small enough rotation period, it has good circular polarization maintaining ability. At the same time, due to the existence of high internal stress, it retains the good ability of polarization-maintaining optical fiber to resist external interference and internal defects, and is suitable for the application of all-optical current transformers. Rotary optical fiber can essentially improve the environmental adaptability of optical fiber current sensor, ensure that the sensor meets the actual application requirements, and is a key sensing component of high-precision optical fiber broadband large current measurement instrument.

[0003] There are two ways to prepare rotary optical fiber, offline and online. The rotary optical fiber prepared by the offline torsion process has a large additional torsion stress and insufficient strength reliability, and cannot be applied on a large scale. Therefore, the current mainstream preparation method is to realize it by rotating the optical fiber preform online during drawing, i.e. the online preparation method. In order to produce stably, a certain drawing tension will be applied to the optical fiber during drawing. Under the combined action of the torsion force of the preform rotation and the drawing tension, the optical fiber coming out of the drawing furnace will also be twisted to a certain extent. Optical fiber twisting usually brings the following two problems: first, it will cause the optical fiber to appear external torsion during coating, which is a kind of coating consistency defect, and this defect will bring problems in the reliability of the subsequent use of rotary optical fiber; second, the torsion of the optical fiber will offset the rotation of the preform to a certain extent, resulting in a certain deviation of the actual rotation pitch from the designed value. The higher the rotation speed of the preform and the greater the drawing tension, the higher the degree of torsion of the optical fiber. Therefore, in order to alleviate the external torsion phenomenon, rotary optical fiber preparation usually adopts low-tension drawing, such as a drawing speed of 2 m / min and a drawing tension of <20 g.

[0004] However, the low-tension drawing of the rotary polarization-maintaining optical fiber online preparation process means that the optical fiber is more susceptible to unstable airflow and more prone to shaking, and the strength of the optical fiber will be poorer. At the same time, low-tension drawing also means higher drawing temperature, and the viscosity of the preform taper is smaller. In the case of high-speed rotation, the taper will deviate from the alignment center faster, resulting in problems such as coating, strength and tower breakage, and thus not enough length can be obtained. Moreover, under high-temperature drawing, the attenuation of the optical fiber will be greater due to the diffusion of boron elements in the stress zone. SUMMARY

[0005] In view of the above defects or improvement needs of the prior art, the present application provides a high-tension online drawing device, system, method and product for a polarization maintaining optical fiber, which aims to form a vortex of coating resin in a conical dish by a paddle, and apply a circumferential friction force opposite to the rotation direction to the bare optical fiber passing therethrough, so as to overcome the torsion of the polarization maintaining optical fiber during drawing, so that the polarization maintaining optical fiber can be drawn under a larger drawing tension, thereby solving the technical problems of poor strength, short segment length and high attenuation caused by drawing the polarization maintaining optical fiber under low tension.

[0006] To achieve the above-mentioned purpose, according to one aspect of the present application, a high-tension online drawing device for a polarization maintaining optical fiber is provided, characterized in that it comprises a paddle and a conical dish coaxially matched; the axial direction of the device is coincident with the passing direction of the optical fiber;

[0007] The paddle is an axial flow paddle, and the rotation direction of the paddle is opposite to the rotation direction of the preform rod.

[0008] The lower part of the inner cavity of the conical dish is an inverted cone, and a coating die is arranged below the conical dish.

[0009] The paddle shaft and the conical dish are filled with liquid coating resin.

[0010] Preferably, the high-tension online drawing device for a polarization maintaining optical fiber, when working, the bare optical fiber enters the device along the axial direction and passes out through the coating die, and the coating resin forms a vortex under the driving of the rotating paddle, and applies a circumferential friction force opposite to the rotation direction of the preform rod to the bare optical fiber passing therethrough.

[0011] Preferably, the high-tension online drawing device for a polarization maintaining optical fiber, the paddle has a hollow central shaft, and the central shaft is located in the upper part of the conical dish.

[0012] Preferably, the high-tension online drawing device for a polarization maintaining optical fiber, the length of the central shaft accounts for 1 / 3-1 / 2 of the height of the inner cavity of the conical dish, the cross-sectional area of the central shaft accounts for 1 / 25-1 / 4 of the cross-sectional area of the inner cavity of the conical dish, the diameter of the hollow central shaft is greater than 5 mm, and preferably does not exceed 20 mm.

[0013] Preferably, the high-tension online drawing device for a polarization maintaining optical fiber, there is a gap between the paddle and the conical dish.

[0014] Preferably, the high-tension online drawing device for a polarization maintaining optical fiber, the paddle is fixed to the side wall of the conical dish.

[0015] Preferably, the high-tension online drawing device for a polarization maintaining optical fiber, there is a gap between the paddle and the fiber passing channel, and the fiber passing channel refers to the area covered by the possible swinging range of the optical fiber.

[0016] Preferably, the high-tension online drawing device for the rotary polarization-maintaining optical fiber has a side wall of the conical dish with at least an inner layer and an outer layer.

[0017] Preferably, the high-tension online drawing device for the rotary polarization-maintaining optical fiber has circulating water injected between the inner layer and the outer layer for water bath temperature control.

[0018] According to another aspect of the present application, there is provided a high-tension online drawing system for the rotary polarization-maintaining optical fiber, characterized in that the inner coating and / or outer coating coating device of the rotary polarization-maintaining optical fiber drawing tower adopts the high-tension online drawing device for the rotary polarization-maintaining optical fiber provided by the present application.

[0019] Preferably, the high-tension online drawing system for the rotary polarization-maintaining optical fiber has the inner coating coating device of the rotary polarization-maintaining optical fiber drawing tower adopting the high-tension online drawing device for the rotary polarization-maintaining optical fiber provided by the present application.

[0020] According to another aspect of the present application, there is provided a high-tension online drawing method for the rotary polarization-maintaining optical fiber, characterized in that the optical fiber drawing is performed by using the high-tension online drawing system for the rotary polarization-maintaining optical fiber provided by the present application.

[0021] Preferably, the high-tension online drawing method for the rotary polarization-maintaining optical fiber has a fiber drawing tension of ≥30 g, a preform rotating speed of 100-10000 r / min, a drawing speed of 1-5 m / min, and a rotating pitch of 0.5-10 mm.

[0022] Preferably, the high-tension online drawing method for the rotary polarization-maintaining optical fiber has a resin viscosity of 3000-7000 cps and a coating temperature of 25-60℃.

[0023] According to another aspect of the present application, there is provided a rotary polarization-maintaining optical fiber drawn according to the high-tension online drawing method for the rotary polarization-maintaining optical fiber provided by the present application.

[0024] Preferably, the rotary polarization-maintaining optical fiber has a rotating pitch of 0.5-10 mm, a drawing segment length of 450 m to 3000 m, and a transmission loss of less than 1.0 dB / km @ 1310 nm.

[0025] Overall, the above technical solutions conceived by the present application can achieve the following beneficial effects compared with the prior art:

[0026] The present application provides a high-tension online drawing device for the rotary polarization-maintaining optical fiber, which forms a vortex of the liquid coating resin in the conical dish by the paddle, so that the fluid acts on the bare optical fiber passing therethrough, applies a circumferential friction force opposite to the rotating direction of the preform to the bare optical fiber, weakens the torsion of the optical fiber, helps to stabilize the optical fiber, so that the optical fiber can be drawn at a higher tension, and the drawing tension exceeds 30 g.

[0027] The high-tension online drawing system for the high-birefringence fiber provided by the application adopts the device to replace the coating cup of the existing drawing tower, without adding other mechanisms, and is suitable for modification on the existing rotary drawing system.

[0028] The high-tension online drawing system for the high-birefringence fiber provided by the application has the advantages that the fiber prepared by the high-tension drawing process has lower attenuation, higher strength, longer segment length, more accurate rotation pitch distribution, and better appearance consistency and environmental reliability. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a structure schematic diagram of the high-tension online drawing device for the high-birefringence fiber provided by the embodiment 1 of the application;

[0030] Figure 2 is a structure schematic diagram of the high-tension online drawing device for the high-birefringence fiber provided by the embodiment 2 of the application;

[0031] Figure 3 is a structure schematic diagram of the high-tension online drawing system for the high-birefringence fiber provided by the embodiment 3 of the application.

[0032] Figure 4 is an end surface schematic diagram of the high-birefringence fiber prepared by the embodiment of the application;

[0033] Figure 5 is a cross-sectional schematic diagram of the high-birefringence fiber prepared by the embodiment of the application.

[0034] In all the drawings, the same reference signs are used to represent the same elements or structures, in which: 1 is the high-tension online drawing device for the high-birefringence fiber, 2 is the bare optical fiber, 3 is the synchronous pulley of the paddle, 4 is the paddle, 5 is the coating material, 6 is the conical dish with a hollow water channel, 7 is the coating mold, 8 is the high-tension online drawing device for the high-birefringence fiber, 9 is the synchronous pulley of the conical dish, 10 is the conical dish with a paddle, 11 is the spiral heating rod, 12 is the rotary chuck, 13 is the optical fiber preform, 14 is the drawing furnace, 15 is the first curing furnace, 16 is the conventional coating device, 17 is the second curing furnace, 18 is the finished optical fiber, 19 is the core, 20 is the cladding, 21 is the stress region, 22 is the inner coating layer, 23 is the outer coating layer, and 24 is the rotation pitch. DETAILED DESCRIPTION

[0035] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0036] The present application provides a high-tension online drawing device for a polarization maintaining optical fiber, which comprises a paddle and a conical dish coaxially matched; the axial direction of the device is coincident with the passing direction of the optical fiber;

[0037] The paddle is an axial flow paddle, and the rotating direction of the paddle is opposite to the rotating direction of the preform rod.

[0038] The lower part of the inner cavity of the conical dish is an inverted cone, and a coating die is arranged below the conical dish.

[0039] Liquid coating resin is injected between the paddle shaft and the conical dish.

[0040] During operation, the bare optical fiber enters the device along the axial direction and passes out through the coating die, and the coating resin forms a vortex under the driving of the rotating paddle, and applies a circumferential friction force opposite to the rotating direction of the preform rod to the bare optical fiber in the vortex, so as to balance the torsional force caused by the rotation of the preform rod and stabilize the shaking of the optical fiber.

[0041] There are two representative paddle driving modes: one is a central shaft power, and the other is an outer peripheral power.

[0042] When the central axis is used as the power source, the paddle has a hollow central axis, and the central axis is driven by the motor to drive the paddle to rotate. This driving mode has good concentricity, good stability, and simple structure. At this time, the optical fiber needs to pass through the central axis, so the central axis is hollow. In the preferred embodiment, the central axis is located in the upper part of the conical dish, so that the remaining part of the optical fiber below is in full contact with the coating resin, thereby applying a circumferential friction force to the optical fiber by the liquid coating resin. Therefore, the length ratio and cross-sectional area ratio of the central axis are one of the important factors affecting the stability of the optical fiber: if the length ratio of the central axis is too small, the stability of the paddle is poor, which leads to unstable vortex of the coating resin; if the length ratio of the central axis is too large, the coating resin cannot fully contact the optical fiber, and the friction force applied is limited. In both cases, the optical fiber cannot be well stabilized. The larger the cross-sectional area ratio of the central axis, the smaller the paddle area, which weakens the liquid disturbance generated by the paddle. The hollow cross-sectional area of the central axis needs to cover the possible swing range of the optical fiber, so it cannot be too small. Considering the above factors, the length of the central axis is designed to be 1 / 3 to 1 / 2 of the height of the inner cavity of the conical dish, to ensure good paddle stability and coating vortex effect; the cross-sectional area of the central axis is 1 / 25 to 1 / 4 of the cross-sectional area of the inner cavity of the conical dish, to ensure a large enough paddle area. The diameter of the hollow central axis is greater than 5 mm, and is preferably not more than 20 mm, to ensure that the vortex formed by the coating resin effectively acts on the optical fiber, and the central axis does not cause insufficient force due to isolation. In addition, there is a gap between the paddle and the conical dish to reduce liquid turbulence and form a stable vortex.

[0043] When the outer periphery is used as the power source, the paddle is fixed to the side wall of the conical dish, and the side wall is driven by the motor to drive the paddle to rotate. This driving mode has good stability, a larger contact range with the optical fiber, and better stability. There is a gap between the paddle and the optical fiber passage, and the vortex not only generates a friction force in the circumferential direction, but also has a component in the axial direction of the optical fiber, which can more obviously help to stabilize the swinging optical fiber. The optical fiber passage refers to the area covered by the possible swing range of the optical fiber.

[0044] In the preferred embodiment, the side wall of the conical dish has at least an inner layer and an outer layer, which can achieve the effect of heat preservation or temperature control. In order to more accurately control the temperature and thereby control the viscosity of the coating resin, stabilize the friction force of the vortex on the surface of the optical fiber, circulating water is injected between the inner layer and the outer layer for water bath temperature control.

[0045] The rotating polarization maintaining optical fiber high-tension online drawing system provided by the present application uses the rotating polarization maintaining optical fiber high-tension online drawing device provided by the present application as the inner coating and / or outer coating device of the rotating polarization maintaining optical fiber drawing tower. Preferably, the inner coating device uses the rotating polarization maintaining optical fiber high-tension online drawing device provided by the present application.

[0046] The application provides a high-tension on-line drawing method for a rotary polarization-maintaining optical fiber, wherein the drawing tension of the optical fiber is greater than or equal to 30 g, preferably between 30 g and 60 g, more preferably between 40 g and 60 g, the rotation speed of the preform rod is 100 r / min to 10000 r / min, preferably between 200 r / min and 800 r / min, more preferably between 400 r / min and 800 r / min, and the drawing speed is 1 to 5 m / min. The drawing tension of the optical fiber is measured by using NCTM-2 of CERSA MC1 company.

[0047] The resin used has a viscosity of 3000 to 7000 cps, and the coating temperature is 25 to 60 ℃. The greater the viscosity of the resin, the greater the torsional force applied to the optical fiber under the same rotation speed; the higher the coating temperature, the smaller the viscosity of the resin; and the size of the torsional force can be adjusted by selecting a resin with different initial viscosity and coating temperature.

[0048] The prepared rotary polarization-maintaining optical fiber has a rotation pitch of 0.5 to 10 mm.

[0049] Since the drawing tension is greater, the drawing temperature is lower, the rod taper is slightly smaller, the drawing length is longer, the shaking is smaller, the probability of collision is smaller, the rotary polarization-maintaining optical fiber has a longer drawing section, the drawing section is longer than 550 m, and the preferred scheme reaches 800 m to 1000 m. Since the optical fiber is more stable during the drawing process, the pitch of the rotary polarization-maintaining optical fiber is more accurate; since the temperature of the drawing furnace is low, the boron in the stress region diffuses less to the core, the optical fiber has lower attenuation, and the transmission loss is less than 1.0 dB / km@1310 nm.

[0050] The following is an example:

[0051] Example 1

[0052] The high-tension on-line drawing device for the rotary polarization-maintaining optical fiber provided in the example comprises a paddle and a conical dish that are coaxially matched, as shown in the drawing, the axial direction of the device is coincident with the passing direction of the optical fiber, the paddle is an axial flow paddle, the rotation direction of the paddle is opposite to the rotation direction of the preform rod, the inner cavity of the conical dish is inverted conical at the lower part, a coating die is arranged below the conical dish, and the paddle shaft and the conical dish are filled with liquid coating resin. Figure 1 During operation, the bare optical fiber enters the device along the axial direction and passes out through the coating die, the coating resin forms an eddy current under the driving of the rotating paddle, and a circumferential friction force opposite to the rotation direction of the preform rod is applied to the bare optical fiber in the device to balance the torsional force caused by the rotation of the preform rod and stabilize the shaking of the optical fiber.

[0053]

[0054] ​The paddle driving mode of the embodiment is middle shaft power: the paddle has a hollow middle shaft, which is installed in the center of the conical dish through a bearing, and a synchronous pulley is installed outside, so that the middle shaft can be driven by a motor and transmitted by a synchronous belt to rotate at a constant speed around the central axis inside the conical dish. The hollow of the middle shaft can pass the optical fiber from the middle, and the lower part of the rotating middle shaft is a spiral whole paddle. When it rotates at a constant speed, the paddle will uniformly stir the coating in a ring direction, forming a ring vortex. The remaining part of the optical fiber below is in full contact with the coated resin, so that the optical fiber is subjected to a circumferential friction force from the liquid coated resin. The length of the middle shaft accounts for 1 / 3 of the height of the inner cavity of the conical dish, the cross-sectional area of the middle shaft accounts for 1 / 25 of the cross-sectional area of the inner cavity of the conical dish, the diameter is 10 mm, the size of the blade is 45 mm, and the inner diameter of the coating cup is 50 mm. There is a gap between the paddle and the conical dish to reduce liquid turbulence and form a stable vortex.

[0055] The side wall of the conical dish has at least an inner layer and an outer layer to form a hollow water channel, and each of the upper and lower parts is provided with a water outlet and a water inlet for water bath circulation heating of the coating in the conical dish to control the temperature of the water bath.

[0056] Embodiment 2

[0057] The rotating polarization maintaining optical fiber high-tension on-line drawing device provided by the embodiment, as shown in Figure 2 , includes a paddle and a conical dish that are coaxially matched; the axial direction is coincident with the direction of the optical fiber passing through; the paddle is an axial flow paddle, and the rotating direction is opposite to the rotating direction of the preform rod; the inner cavity of the conical dish is in the shape of an inverted cone at the lower part, and a coating mold is arranged below; and the paddle shaft and the conical dish are filled with liquid coating resin.

[0058] When working, the bare optical fiber enters the device along the axial direction and passes out through the coating mold. The coating resin forms a vortex under the driving of the rotating paddle, and applies a circumferential friction force opposite to the rotating direction of the preform rod to the bare optical fiber in it, so as to balance the torsional force brought by the rotation of the preform rod and stabilize the shaking of the optical fiber.

[0059] The paddle driving mode of the embodiment is peripheral power: the side wall of the conical dish is provided with a ring paddle, and the conical dish is installed in a fixed support sleeve through two upper and lower bearings. The upper part is provided with a synchronous pulley, and the synchronous pulley is driven by a motor and a synchronous belt to realize the constant speed rotation of the conical dish. When the conical dish rotates, it drives the coating to generate a ring vortex. There is a gap between the paddle and the optical fiber passing channel, and the vortex not only generates a friction force in the circumferential direction of the optical fiber, but also helps to stabilize the shaken optical fiber in the axial direction of the friction force.

[0060] The optical fiber passing channel is inserted into the spiral heating rod from the upper part, which can heat the coating without affecting the vortex.

[0061] Embodiment 3

[0062] The high-tension online drawing system for rotating polarization-maintaining optical fibers provided in this embodiment, such as Figure 3 As shown, the following components are arranged coaxially from top to bottom: a rotating chuck, a drawing furnace, a rotating polarization-maintaining fiber high-tension online drawing device provided in Example 1 or 2 as an inner coating cup, a first curing furnace, an outer coating cup, and a second curing furnace.

[0063] The panda-shaped rotating polarization-maintaining fiber was fabricated using the high-tension online drawing system for rotating polarization-maintaining fiber provided in this embodiment. Its end-face structure is as follows: Figure 4 As shown, from the inside out, it includes: core, cladding, inner coating, and outer coating. The cladding has symmetrical boron-doped stress regions on both sides of the core, and its cross-sectional structure is as follows. Figure 5 As shown, the stress zone is in a rotating shape and has a preset rotation pitch.

[0064] The fiber drawing process is as follows: The fiber preform is clamped in a rotating chuck, which rotates at a constant speed during drawing. The preform is melted at high temperature in a drawing furnace and drawn into a bare fiber of the required diameter under a certain drawing tension. The inner layer coating is applied using the high-tension online drawing device for polarization-maintaining fiber provided in Example 1 or 2, and then cured in a first curing furnace. Then, the outer layer is coated and cured, using a conventional outer coating cup. Both the inner and outer layer coatings are conventional acrylic resin coatings, with the inner layer having a room temperature viscosity of 5800 cps. Different drawing processes were achieved by adjusting the chuck speed, drawing tension, and blade speed. The parameter information for the drawn fiber is shown in Table 1 below. It can be seen that increasing the rotating drawing tension using the devices in Examples 1 and 2 can achieve longer segment lengths, lower attenuation, and a pitch closer to the design value.

[0065] Table 1. Process parameters and testing of rotating polarization-maintaining fiber drawing process.

[0066]

[0067]

[0068] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A coating device for a high tension on-line drawing of a polarization maintaining optical fiber, characterized by comprising: The paddle and the conical dish are coaxially matched; The axial direction of the paddle is coincident with the fiber passing direction; The paddle is an axial flow paddle, and the rotating direction of the paddle is opposite to the rotating direction of the preform rod; The lower part of the inner cavity of the conical dish is an inverted cone, and a coating mold is arranged below the lower part; Liquid coating resin is injected between the paddle and the conical dish; In operation, the bare optical fiber enters the device along the axial direction and passes out through the coating mold, and the coating resin forms a vortex under the driving of the rotating paddle to apply a circumferential friction force to the bare optical fiber in the opposite direction to the rotating direction of the preform rod; the fiber drawing tension is greater than or equal to 30 g.

2. The coating apparatus for a high tension on-line drawing of a polarization maintaining fiber according to claim 1, wherein The paddle has a hollow central shaft; the central shaft is located in the upper part of the conical dish.

3. The coating apparatus for a high tension on-line drawing of a polarization maintaining fiber according to claim 2, wherein The length of the central shaft accounts for 1 / 3 to 1 / 2 of the height of the inner cavity of the conical dish, the cross-sectional area of the central shaft accounts for 1 / 25 to 1 / 4 of the cross-sectional area of the inner cavity of the conical dish, the diameter of the hollow central shaft is greater than 5 mm and does not exceed 20 mm.

4. The coating apparatus for a high tension on-line drawing of a polarization maintaining fiber according to claim 2, wherein There is a gap between the paddle and the conical dish.

5. The coating apparatus for high tension on-line drawing of a polarization maintaining optical fiber in rotation according to claim 1, wherein The paddle is fixed to the side wall of the conical dish.

6. The coating apparatus for high tension on-line drawing of a polarization maintaining optical fiber in rotation according to claim 5, wherein There is a gap between the paddle and the fiber passing channel, and the fiber passing channel refers to the area covered by the possible swinging range of the fiber.

7. The coating apparatus for high tension on-line drawing of a polarization maintaining optical fiber in rotation according to claim 1, wherein The side wall of the conical dish has at least an inner layer and an outer layer.

8. The coating apparatus for high tension on-line drawing of a polarization maintaining optical fiber in rotation according to claim 7, wherein Circulating water is injected between the inner layer and the outer layer for water bath temperature control.

9. A high tension on-line drawing system for a polarization maintaining optical fiber, characterized by, The inner coating and / or outer coating device of the spinning polarization maintaining fiber drawing tower adopts the coating device for high-tension online drawing of the spinning polarization maintaining fiber according to any one of claims 1 to 8.

10. The high tension on-line drawing system for a spun polarization maintaining optical fiber as defined in claim 9 wherein, The inner coating device of the spinning polarization maintaining fiber drawing tower adopts the coating device for high-tension online drawing of the spinning polarization maintaining fiber according to any one of claims 1 to 8.

11. A high tension on-line drawing method of a polarization maintaining optical fiber of the rotary type, characterized by, The spinning polarization maintaining fiber is drawn by using the high-tension online drawing system of the spinning polarization maintaining fiber according to claim 9 or 10.

12. The high tension on-line drawing method of a polarization maintaining optical fiber according to claim 11, wherein The fiber drawing tension is greater than or equal to 30 g, the rotating speed of the preform rod is 100 to 10,000 r / min, the drawing speed is 1 to 5 m / min, and the rotating pitch is 0.5 to 10 mm.

13. The high tension on-line drawing method of polarization maintaining optical fiber of claim 11 wherein, The viscosity of the resin is 3,000 to 7,000 cps, and the coating temperature is 25 to 60°C.

14. A polarization maintaining optical fiber, characterized by, The spinning polarization maintaining fiber is drawn according to the high-tension online drawing method of the spinning polarization maintaining fiber according to any one of claims 11 to 13.

15. The polarization maintaining fiber according to claim 14, wherein The rotating pitch is 0.5 to 10 mm, the drawing length is 450 m to 3,000 m, and the transmission loss is less than 1.0 dB / km at 1310 nm.

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