阅读说明：本技术 一种气体包层低损耗偏振光纤 (Gas cladding low-loss polarization optical fiber ) 是由 不公告发明人 于 2020-07-09 设计创作，主要内容包括：本发明涉及一种气体包层低损耗偏振光纤,由一个薄片状的芯、紧紧敷贴在薄片状芯上下两个平滑表面的气体包层、固体外包层和有机树脂保护涂层组成。本发明所提供的气体包层低损耗偏振光纤,独创的光纤薄片芯结构设计使得光纤能够用做起偏器,不但确保了传输偏振光极其稳定的偏振性能,而且所有的非横模能量全部被截止,消除了外界的干扰和噪声；超高纯石英玻璃作芯,最纯净的气体作包层组成了当今世界上最完善的光波导,把材料吸收和波导缺陷导致的光纤损耗都降到了最低；尤其是气体包层偏振光纤的制造过程全部是纯物理过程,淘汰了光纤生产的OVD、VAD、MCVD或PCVD等化学沉积过程,不但消除了光纤生产对环境的严重污染,而且还大幅度地降低了生产成本。(The invention relates to a gas-clad low-loss polarizing fiber, which consists of a sheet-shaped core, a gas cladding tightly applied to the upper and lower smooth surfaces of the sheet-shaped core, a solid outer cladding and an organic resin protective coating. According to the gas cladding low-loss polarization optical fiber provided by the invention, the optical fiber can be used as a polarizer due to the original optical fiber sheet core structure design, so that the extremely stable polarization performance of the transmitted polarized light is ensured, all non-transverse mode energy is cut off, and the external interference and noise are eliminated; the ultra-pure quartz glass is used as a core, the purest gas is used as a cladding to form the most perfect optical waveguide in the world at present, and the optical fiber loss caused by material absorption and waveguide defects is reduced to the lowest; especially, the manufacturing process of the gas cladding polarization optical fiber is a pure physical process, chemical deposition processes such as OVD, VAD, MCVD or PCVD and the like in optical fiber production are eliminated, not only is the serious pollution of the optical fiber production to the environment eliminated, but also the production cost is greatly reduced.)

1. A gas-clad low-loss polarizing fiber, characterized by: the optical fiber consists of a sheet-like core, gas cladding layers closely applied to the upper and lower smooth surfaces of the sheet-like core, a solid outer cladding layer, and an organic resin protective coating.

2. The gas-clad low-loss polarizing fiber of claim 1, wherein: the optical fiber core material does not need to be doped with any chemical elements, and adopts the ultra-pure quartz glass which is the same as the solid outer cladding layer.

3. The gas-clad low-loss polarizing fiber of claim 1, wherein: the light transmitted in the core of the flake-like optical fiber is absolutely fully polarized light.

4. The gas-clad low-loss polarizing fiber of claim 1, wherein: the solid outer cladding is connected with two transverse ends of the flaky optical fiber core, so that the possibility of HElly light transmission is eliminated.

5. The gas-clad low-loss polarizing fiber of claim 1, wherein: the sheet-shaped optical fiber core enables the shading ratio of the optical fiber to reach 100 dB.

6. The gas-clad low-loss polarizing fiber of claim 1, wherein: the ultra-high purity gas is encased in the optical fiber by a solid outer cladding.

7. The gas-clad low-loss polarizing fiber of claim 1, wherein: the gas of the gas cladding is closely applied to the upper and lower smooth surfaces of the sheet-like optical fiber core, no gap or defect is generated between the core and the cladding, and the scattering caused by the imperfect waveguide structure is reduced to the minimum.

8. The gas-clad low-loss polarizing fiber of claim 1, wherein: there is no stress on the structural interface between the gas cladding and the core, and the nonlinear effects such as elastic reflection and elastic birefringence of light do not occur on the waveguide interface formed by the fiber core and the cladding, thereby greatly reducing the consumption of transmission energy.

Technical Field

The invention relates to an optical fiber, in particular to a gas cladding low-loss polarization optical fiber.

Background

The optical fiber is a great invention of the present generation, and from a multimode optical fiber G651 and a single mode optical fiber G652, single mode optical fibers having a plurality of different transmission performances such as G653, G654 to G657 are developed in succession. In 1979, kaminiw et al proposed the concept of polarization maintaining optical fibers, which can greatly increase the transmission capacity of each fiber in coherent communication systems. Research shows that, in the current single-mode optical fiber transmission communication system, regardless of which optical fiber, the maximum transmission capacity is only 1GHz, while the coherent communication system adopts the heterodyne detection technology, and the theoretical transmission capacity of each optical fiber can reach 104-105GHz, which is 1 ten thousand times to 10 ten thousand times of the transmission capacity of each optical fiber in the currently operating optical fiber communication system.

Besides coherent communication, polarization-maintaining optical fibers are widely used for manufacturing the bodies of various sensors, such as detecting temperature, pressure, deformation, and the like. Coherent optical fiber gyroscopes, optical fiber power transformers, etc. are also the most advanced technical field of polarization maintaining optical fiber applications today.

At present, the most popular polarization maintaining optical fiber in the domestic and foreign markets is mainly one product, which is called as a panda optical fiber. The panda fiber is because its cross-section has two black spots similar to panda eyes, as shown in fig. 1. The panda fiber has two panda eyes, and two boron-doped quartz glass rods are implanted into two sides of the fiber core by a mechanical processing method in the process of manufacturing the fiber preform. Boron-doped rods on two sides of the core break the circular symmetry of the cross section of the optical fiber, the difference between a propagation constant beta x of a transverse mode HE11x and a propagation constant beta y of a longitudinal mode HE11y is caused by the asymmetrical structure of the cross section and strong mechanical stress of the boron-doped rods and the cladding of the optical fiber, and beta x is not equal to beta y, so that the degeneracy and the cross coupling of the transverse mode and the longitudinal mode are hindered, the birefringence delta beta is generated between the modes, and the larger beta x is greater than beta y, and the better the polarization state of the polarized light transmitted by the optical fiber is kept when the delta beta is larger. Panda fibers use the intermodal birefringence Δ β to maintain the polarization state of the transmitted light.

However, the birefringence Δ β between the panda fiber modes is induced by two factors, stress and refractive index difference. The boron-doped quartz glass rods implanted into the two sides of the optical fiber core have great difference with the glass structure of the cladding, the refractive indexes have obvious difference, and the refractive index difference induces strong birefringence; meanwhile, strong mechanical internal stress exists between the cladding and the boron-doped rod, and strong birefringence is also induced by the mechanical internal stress. Strong birefringence hinders the degeneracy and cross-coupling of HE11x and HE11 y. Therefore, the panda polarization maintaining fiber uses strong birefringence around the core to break the balance between HE11x and HE11y, so as to maintain the polarization state of the transmitted light, and the strength of birefringence directly determines the polarization state of the transmitted light. It is clear that the birefringence around the panda fiber core is determined mainly by two components, the birefringence due to the difference in refractive index and the birefringence induced by mechanical internal stress are determined together. Therefore, the polarization maintaining fibers such as pandas and bowknots are called stress polarization maintaining fibers. It is well known in the middle school times that mechanical internal stress is very sensitive to environmental temperature change, and the mechanical internal stress on the interface of the panda fiber cladding and the boron-doped part changes with the environmental temperature change, and certainly, the birefringence induced by the internal stress changes with the environmental temperature change. Since the polarization state of the transmitted light is ensured by the birefringence Δ β, which changes with the change in the ambient temperature, the polarization state of the transmitted light is of course not stabilized.

Therefore, poor temperature performance is a technical performance defect of panda polarization maintaining optical fibers. Besides the insufficient temperature performance, panda fibers have two other important technical performance drawbacks:

(1) inability to withstand high temperature broiling and cosmic ray radiation: the optical waveguide of the panda fiber consists of a germanium-doped quartz glass core and a pure quartz glass cladding. Germanium element is not stable enough in the grid of the glass structure of the optical fiber core, when panda optical fiber is subjected to high-temperature roasting or cosmic ray radiation, the germanium element in the core can diffuse and dissociate from the core of the optical fiber into the cladding, once partial germanium element particles in the optical fiber core cross the interface between the core and the cladding and enter the optical fiber cladding, the refractive index of the cladding can rapidly rise, the optical waveguide structure of the optical fiber can be damaged, polarized light and all other light can not be effectively transmitted any more, and the optical fiber loses the light transmission function. However, many sensing devices must operate under harsh environmental conditions, and in particular, the fiber optic coherent gyroscope must be exposed to cosmic rays following the entry of the cosmic vehicle into outer space. The inability to withstand high temperature broiling and cosmic ray radiation is the second major technical performance drawback of panda fibers.

(2) Poor splicing performance: the cross section of the panda optical fiber is not in a circular symmetry structure, corresponding parts of two end faces are difficult to align when two sections are connected, if the received power of a reference output end is adopted, the maximum value of the received power is considered to be the optimal connection, the output end power is overlapped after HE11x and HE11y are disordered, and therefore the maximum value of the received power is not the optimal connection of the polarization maintaining optical fiber of pandas and the like. Panda fiber can only maintain the polarization state of the transmitted polarized light and cannot be used as a polarizer, so that the quality of the connection cannot be judged by a method for measuring the extinction ratio. If the quality of the connection cannot be judged, the connection cannot be repeated indefinitely. Panda optical fibers have poor splicing performance, and the technical development of coherent optical communication is hindered. This is the third major technical performance drawback of panda fibers.

Although panda polarization maintaining optical fiber has a plurality of key technical performance defects, market sales at home and abroad are greatly increased year by year, mainly because: the development of artificial intelligence technology in the world is the core of the development of industrial technology, military and other technologies, and one of the key bases of the development of intelligent technology is sensing. If the brain perception of machines, equipment, operating systems and the like cannot be given, the brain cannot acquire information of various condition changes of objects, environments and the like, no information is transmitted to the brain, and the brain cannot think, reason and calculate to send instructions, so that the sensing technology is one of the key foundations of the development of the current artificial intelligence technology. The coherent optical fiber sensor has the highest sensitivity, the widest detection range, the smallest volume and the lightest weight at present. Therefore, the market for polarizing fibers has grown substantially in the near future and year after year. Aiming at the sales volume of domestic and foreign markets which is greatly increased year by year and a plurality of key technical performance defects of panda optical fiber products, the international innovation achievement of 'a gas cladding low-loss polarization optical fiber' is successfully designed and researched.

Disclosure of Invention

The invention aims to solve the technical problems that the existing optical fiber has poor temperature performance, cannot resist high-temperature roasting and cosmic ray radiation, is difficult to splice and the like.

The technical scheme for solving the technical problems is as follows: a low-loss gas-clad polarizing fiber is composed of a sheet-like core, gas cladding tightly coated on the upper and lower surfaces of the sheet-like core, solid outer cladding, and organic resin protective coating.

Furthermore, the optical fiber core material does not need to be doped with any chemical elements, and the ultra-pure quartz glass which is the same as the solid outer cladding layer is adopted.

Further, the light transmitted in the core of the flake-like optical fiber is absolutely fully polarized light.

Further, the solid outer cladding layer is attached to both lateral ends of the laminar optical fiber core, eliminating the possibility of light propagation by HE11 y.

Further, the light shielding ratio of the optical fiber is up to 100dB due to the thin sheet-shaped optical fiber core.

Further, the ultra-high purity gas is encased in the fiber by a solid outer cladding.

Furthermore, the gas of the gas cladding is closely applied to the upper and lower smooth surfaces of the core of the flake optical fiber, no gap or defect is generated between the core and the cladding, and the scattering caused by the imperfect waveguide structure is reduced to the minimum.

Furthermore, no stress exists on the structural interface between the gas cladding and the core, and nonlinear effects such as elastic reflection and elastic birefringence of light do not occur on the waveguide interface formed by the fiber core and the cladding, so that the consumption of transmission energy is greatly reduced.

From the basic knowledge of optics or the light transmission principle of optical fibers: when light travels from an optically dense material (e.g., a fiber core) to an optically thin material (e.g., a fiber cladding), the light will be totally reflected at the interface between the two materials when the incident angle is larger than the critical angle, and then returns to the optically dense material to continue traveling forward in the optically dense material (e.g., the fiber core), as shown in fig. 3.

The flaky optical fiber core adopts optical fiber grade ultra-pure quartz glass with ultra-low hydroxyl, and the refractive index n1 is about 1.457; the refractive index n2 of the ultra-pure low molecular weight inert gas applied closely to both the upper and lower smooth surfaces of the sheet is approximately equal to 1. n1 is greater than n2, the lamellar core and the gas cladding combine to form a perfect plane optical waveguide, when the light with light vector fluctuation transversely, HE11x mode, propagates forwards in the optical fiber core, the light will generate total reflection on the optical interface formed by the core and the upper and lower gas cladding, and the light is always transmitted forwards along the axis in the optical fiber core. The transmission principle is the same as that of the conventional single-mode optical fiber.

However, the light propagation path of the longitudinal mode HE11y in the sheet-like optical fiber core is completely different: the longitudinal wave vibration vector direction is perpendicular to the upper plane and the lower plane of the flaky optical fiber core, the vibration is restricted, and the propagation direction is perpendicular to the vibration vector direction. The optical fiber core is directly connected with the outer cladding layer, as shown in figure 2, the optical fiber core and the outer cladding layer are made of the same material glass structure and have the same refractive index, an interface does not exist between the core and the solid outer cladding layer, when the light of HE11y is transmitted from the core to the solid outer cladding layer, no optical structure is used for generating total reflection, and the structure of the optical fiber does not provide waveguide for the transmission of the HE11y mode. The longitudinally vibrating light in the fiber core will pass through the solid outer cladding and directly travel through the higher refractive index organic protective coating, be absorbed by the coating, and have no chance to return to the fiber core. Because light has a fundamental property: light rays are always the preferred way of choosing a material with a higher density (relatively higher refractive index) during propagation. The planar optical waveguide formed by the thin-plate optical fiber core and the high-purity gas cladding only provides an optimal medium for guiding the transverse wave HE11x, and does not provide any possibility for transmission of the HE11y mode.

According to the basic concept of polarized light: when the light vector vibrates in a fixed plane only in a fixed direction, the vibration direction is always kept in the fixed plane, and the light is called polarized light. The sheet-shaped optical fiber core limits the light vector to vibrate in a fixed plane only along a fixed direction, and the vibration direction of the sheet-shaped optical fiber core is always kept in the transverse plane of the core, so that the light transmitted in the sheet-shaped optical fiber core is only polarized light, and the optical fiber core is a fine optical polarizer.

The optical waveguide formed by the flaky optical fiber core and the ultra-pure gas cladding provides excellent conditions for light propagation of HE11x, and the propagation constant beta x is large; while the light of the longitudinal mode HE11y has no condition for the waveguide to provide transmission, HE11y cannot be transmitted and its propagation constant β y approaches zero. Therefore, β x > β y blocks the degeneracy and cross-coupling of transverse mode HE11x with longitudinal mode HE11y, ensuring the optimum polarization state of light propagating in the fiber core. By- β x is referred to as birefringence, and the greater Δ β, the more stable the polarization state of light propagating in the fiber core. The birefringence coefficient delta beta of the panda polarization maintaining fiber is about 10-5 orders of magnitude; the birefringence index Δ β of the photonic crystal polarization maintaining fiber is approximately on the order of 10-3. Whereas the birefringence Δ β of our gas-clad low-loss polarizing fiber is close to 0 due to β y, the core β x of the sheet-like fiber is only related to the group refractive index n of the core material.

Δβ＝(-0)-(-1.52)＝-1.52

Δ β is about-1.52, which is about 4 orders of magnitude greater than panda polarization maintaining fiber Δ β p. Therefore, the polarization stability of the transmitted light in the core of the gas-clad low-loss polarization optical fiber is far better than that of a panda polarization maintaining optical fiber and that of a photonic crystal polarization maintaining optical fiber.

The gas-clad low-loss polarization fiber is the same as the conventional single-mode fiber, and the power distribution of a fundamental mode is as follows:

cutoff radius of optical fiber:

diameter of mode field:

according to the requirements of different wavelengths of the transmission system on the mode field diameter, the thickness of the sheet-like core is calculated by the formula:

the working wavelength is 1310nm, and the thickness of the core is 3 +/-1 mu m;

working wavelength 1550nm system, core thickness 4 + -1 μm.

As is clear from FIG. 2, the internal structure of the gas-clad low-loss polarizing fiber is shown in the figure, and the same ultra-high purity quartz glass material without other chemical elements is used for both the core and the solid outer cladding except the gas filled in the gas claddingThere is no layer or boundary between the core and the solid outer cladding, so there is no stress between the core and the gas cladding, nor between the core and the solid outer cladding; because no other chemical impurity elements exist in the core and the cladding, no matter what environment the optical fiber works in, no matter high-temperature roasting or cosmic ray radiation, no chemical element ion diffusion, ionization or migration can occur in the core and the cladding; the gas-clad low-loss polarizing fiber ensures the polarization performance of transmitted light by using the geometric shape of the core of the fiber, the geometric size of the core is the key of the technical performance, however, the high-purity quartz glass has excellent physical performance, is one of the substances with the lowest temperature coefficient in the world at present, and has the expansion and shrinkage rate of 10^-7Therefore, no matter how severe the polarization fiber works in the environment, the technical performance and the stability of the working state of the gas cladding low-loss polarization fiber cannot be damaged due to the change of the environmental temperature, moisture, chemical corrosion, high-temperature roasting, cosmic ray radiation and the like.

The core of the gas cladding low-loss polarization optical fiber is made of ultra-pure quartz glass material, the transmittance of the core is close to the theoretical limit value of a solid transparent material, the optical cladding of the optical fiber adopts ultra-pure gas to combine into the current optimal optical waveguide, and the material absorption loss and the material scattering loss of the waveguide are reduced to the minimum; the gas of the gas cladding is tightly applied to the upper and lower smooth surfaces of the lamellar optical fiber core, no gap and no defect can be generated between the core and the cladding, and the scattering caused by the imperfect waveguide structure is also reduced to the minimum; there is no structural defect between the gas cladding and the core, and no mechanical stress on the interface, so that the nonlinear effects such as elastic reflection and elastic birefringence of light do not occur on the waveguide interface, and the consumption of transmission energy is greatly reduced.

As seen from the cross section of the optical fiber in FIG. 2, the cross section of the gas-clad low-loss polarizing fiber is an ellipse, and the flaky optical fiber core is always coincident with the short axis, so that the prejudgment is provided for the interconnection between the gas-clad low-loss polarizing fibers. As long as the long axis of the two sections of optical fibers is superposed with the long axis and the short axis is superposed with the short axis, the flaky core is superposed with the core. Because the sheet-shaped optical fiber core can be used as a polarizer, the butt joint condition of the two sections of optical fiber cores can be judged by adopting a method for measuring the shading ratio of the polarized optical fiber, the maximum power of the output end is the best butt joint condition of the two sections of optical fibers, and the guarantee is provided for the inexhaustible laser fusion welding or mechanical splicing.

The performance and technical indexes of all the polarization optical fibers and polarization maintaining optical fiber products sold in the market at present can be found on the Internet. At present, international polarization optical fiber and polarization maintaining optical fiber products market the largest number of PANDA optical fibers (Fujikura PANDA fibers) of Fujikura. But does not provide temperature performance, cosmic ray radiation resistance, connectivity and extinction ratio in that it provides all the product technical properties and parameters. The poor temperature performance, the intolerance to cosmic ray radiation and the extremely poor connection performance are common diseases of polarization maintaining optical fiber products of all countries in the world at present, and Fuji panda optical fibers are no exception, and the performances of temperature performance, high temperature roasting resistance, cosmic ray radiation and the like are avoided in the introduction of the technical performance of the products.

In addition, other technical indexes of Fushitong panda fiber are as follows: 3dB/km at 0.85 μm wavelength, as attenuated; the 1.3 μm wavelength attenuation is 1.0 dB/km; the attenuation of the 1.55 mu m wavelength is 0.5dB/km, which is much higher than the detection result of the Renwell gas cladding low-loss polarized optical fiber sample: 2.01 dB/Km; 0.24dB/Km and 0.13 dB/Km.

The extinction ratio is an important index for measuring the polarization state of the transmitted light ensured by the polarization maintaining fiber or the polarization fiber, and the higher the extinction ratio is, the more stable the polarization state of the transmitted light is maintained. The extinction ratios of Fushitong panda fiber, American Tiger polarization maintaining fiber and the like are all about 30dB, while the extinction ratio of a gas-clad low-loss polarization fiber is 92.7dB, and the fiber is the polarization fiber with the highest extinction ratio in the world at present.

The invention relates to a single-mode single-polarization microstructure fiber, a side-leakage photonic crystal fiber and a preparation method thereof, which are invented and patented in China, and the like, and solves the technical defects of polarization maintenance of pandas and the like, poor temperature performance of the polarization fiber and incapability of resisting cosmic ray radiation, but the transmission attenuation of the pandas and the like is over 30 dB/km. The technical standard of international communication systems is < 20 dB/km. Therefore, the side-leakage photonic crystal fiber, the single-mode single-polarization micro-structured fiber, and the like can only be used for manufacturing small sensors, and cannot be used for a fiber coherent communication system and other long-distance coherent optical information transmission and detection systems, and the fiber coil of each phase of the gyroscope needs at least 1000 meters long, so that the sensitivity and the precision of the gyroscope are greatly reduced by 30dB transmission loss.

Compared with international similar products, the flaky optical fiber core of the gas-clad low-loss polarization optical fiber only provides a perfect optical waveguide for HE11x transmission, eliminates two orthogonal degenerations and cross coupling, eliminates parasitic light interference and nonlinearity, enables the extinction ratio to reach 92.7dB, and is the optical fiber with the highest extinction ratio and the most stable transmission of fully polarized light in the world; except the gas filled in the outer protective coating and the inner optical cladding, the optical fiber is made of the same ultra-pure quartz glass material from inside to outside, and structural stress and any stress do not exist between the optical fiber core and the inner gas cladding and between the optical fiber core and the outer solid cladding, so that the stable transmission state of the fully polarized light cannot be influenced no matter how the working environment of the optical fiber changes, the structures and the refractive indexes of the optical fiber core, the gas cladding and the solid outer cladding cannot be changed no matter high-temperature roasting or violent irradiation of cosmic rays, and the optical fiber has the best temperature performance in the world and can better resist the high-temperature roasting and strong cosmic ray radiation; the ultra-high pure gas cladding and the ultra-high pure quartz glass core are combined into the most perfect optical fiber waveguide structure in the world at present, and the optical fiber is the polarizing optical fiber with the lowest transmission attenuation in the world at present; the elliptical cross section can provide prejudgment for optical fiber connection, and any one section of gas cladding low-loss polarization optical fiber can be used as a polarizer, so that endless connection can be realized by using the simplest reference power method; the simple structural design greatly reduces the technical and technological difficulty of production, and is the only polarizing fiber suitable for commercial repeated scale production in the world at present; the production and manufacturing process is a full physical process, no chemical deposition, no strong acid corrosion, no drilling and punching and other mechanical processing are needed, and the polarization optical fiber is the polarization optical fiber which has no pollution and the lowest production cost in the current world production process.

The invention has the beneficial effects that: the excellent technical performance of the gas cladding polarization fiber can greatly improve the resolution and precision of the fiber interference gyroscope and greatly improve the technical performance of various sensors and related high-end equipment; the excellent transmission performance and the inexhaustible connection performance of the gas-clad polarization fiber can promote the development of the optical fiber coherent communication technology; the development of a real-time detection technology of the high-speed railway track is promoted; the development of the real-time detection technology of the oil and gas pipelines is promoted; the development of the real-time detection technology of the ultra-high voltage cable power transmission network is promoted; promoting the improvement and development of optical fiber production technology.

Drawings

FIG. 1 is a cross-sectional view of a panda polarization maintaining fiber.

FIG. 2 is a diagram of a gas-clad low loss polarizing fiber.

Fig. 3 is a schematic diagram of total reflection transmission of an optical fiber.

FIG. 4 is a schematic diagram of the transmission of a gas-clad low-loss polarizing fiber light in a laminated fiber core.

FIG. 5 is a schematic diagram of a gas-clad low-loss polarizing fiber sheet with the core directly connected to the outer solid cladding.

Fig. 6 is a structural diagram of a polarization fiber and a polarization maintaining fiber.

Wherein, in the figure, 1: sheet core, 2: gas envelope, 3: solid coating, 4: and (4) protecting the coating.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.

Detecting the length of the optical fiber to be 22.8 Km;

protective coating material: polyimide optical fiber coating

Temperature test: the total length is 22.8km

Low temperature: 72 hours output end meter reading change of minus 0.01dB at-85 DEG C

High temperature: +92 deg.C (centigrade) 72 hours output end meter reading change +0.003dB

A method for preparing a gas-clad low-loss polarizing fiber comprises the following steps:

the manufacture of the gas-clad low-loss polarization optical fiber comprises 8 steps:

step 1, raw material preparation: a commercial 1200 mm-long solid outer-cladding ultra-pure quartz glass sleeve and an optical fiber core tube with the same length are selected.

Step 2, cleaning and polishing the core tube and the sleeve

Step 3, installing the core tube into the sleeve

And 4, aligning the core tube with one end of the sleeve, then melting and shrinking the aligned end into a rod by using oxyhydrogen flame, and then tapering to manufacture the prefabricated rod.

Step 5, cleaning and polishing the prefabricated rod

And 6, clamping the cleaned and polished prefabricated rod into a wire drawing tower, feeding the prefabricated rod into a high-temperature furnace at 2000 ℃, adding air pressure 36Kpa into the top of the prefabricated rod, and drawing the prefabricated rod into a polarization optical fiber.

Step 7, screening

Step 8. Performance test

The whole manufacturing process has no chemical deposition, no chemical corrosion and no mechanical processing, and is a pure physical manufacturing process.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.