Manufacturing method of non-zero dispersion shift optical fiber preform and prepared preform and optical fiber

Abstract

The invention relates to a manufacturing method of a non-zero dispersion displacement single-mode optical fiber preform and a manufactured preform and optical fiber, which comprises the following steps: depositing an inner cladding and a core layer, depositing the inner cladding and a plurality of core layers in a quartz liner tube through a PCVD (Plasma Chemical Vapor Deposition) process, melting and shrinking to manufacture the core rod, and carrying out heat treatment on the core rod to obtain the non-zero dispersion displacement single-mode optical fiber preform. The method comprises the following steps: heating and melting the deposition tube deposited with the inner cladding and the core layer in a melting lathe to form a core rod containing the core layer and the inner cladding which are integrated, and adjusting the melting outer diameter and out-of-roundness of the core rod by controlling the axial movement speed and the output power change of a heating furnace in the heating and melting process to manufacture an optical fiber preform; and spraying and depositing a pure silicon dioxide outer cladding on the outside of the core rod through an OVD process, or sleeving the core rod with a pure silicon dioxide outer sleeve, and carrying out sintering or melting shrinkage treatment to prepare the non-zero dispersion displacement single-mode optical fiber preform. According to the method, the deposition processing precision can be ensured, and the quality of the core rod in the melting shrinkage process can be improved, so that the accurate manufacturing of the core rod is realized, and the optical fiber performance is further optimized.

Description

Technical Field

[0001] The invention relates to a method for manufacturing a non-zero dispersion-shifted optical fiber preform rod, and the prepared preform rod and optical fiber, belonging to the technical field of optical communication and transmission. Background Art

[0002] In the field of optical fiber communications, non-zero dispersion-shifted single-mode fiber (NZ-DSF) is a key technology developed to address the limitations of traditional optical fiber in wavelength division multiplexing (WDM) systems. Traditional single-mode fiber (corresponding to ITU-T standard G.652 fiber) has zero dispersion in the 1310nm window, but exhibits high dispersion (approximately 17 ps / (nm·km)) in the 1550nm window, limiting transmission rates over long distances. While the 1550nm window has lower loss (approximately 0.2 dB / km), dispersion causes signal pulse broadening, necessitating the frequent use of dispersion compensation modules. Dispersion-shifted DSF fiber (corresponding to ITU-T standard G.653 fiber) shifts the zero dispersion point from 1310nm to 1550nm through waveguide design, reducing dispersion in the 1550nm window. However, this characteristic causes severe four-wave mixing (FWM) nonlinear effects in WDM systems, leading to crosstalk between channels and restricting the application of dense wavelength division multiplexing (DWDM). Non-zero dispersion-shifted fiber (G.655) is a fiber specifically developed for DWDM transmission technology. It overcomes the high dispersion of G.652 fiber (non-dispersion-shifted fiber) and the severe FWM of G.653 fiber (dispersion-shifted fiber) at the low-loss 1550nm wavelength, making it the preferred fiber type for operators' fiber-optic communication systems.

[0003] A non-zero dispersion-shifted optical fiber preform consists of three parts: the core, inner cladding, and outer cladding. The core comprises two to four core layers with varying refractive index profiles. The inner cladding also comprises two to four cladding layers with varying refractive index profiles. The outer cladding is a layer of pure silica glass. Due to the complex refractive index profiles of the core and inner cladding, particularly the small core diameter, the narrow control range for diameter and refractive index, and the high precision required, in-tube plasma chemical vapor deposition (PCVD) is typically used to deposit the core and inner cladding layer by layer, resulting in a core rod with an integrated core and inner cladding. This is then combined with outer cladding glass provided by external vapor deposition (OVD) technology to form a complete optical fiber preform. In-tube PCVD requires a sintering process to form a solid core rod. The existing sintering and melting process is prone to uneven rod diameters due to the uncertainty of the glass softening point and the slow change in furnace heating performance over time. This can lead to localized core non-roundness or gas lines (unsintered cores) in the solid rod, resulting in product rejection. Lower melting and melting temperatures can easily lead to localized gas lines. Higher melting and melting temperatures, while reducing the occurrence of gas lines, can also lead to excessive core non-roundness and even increased bow values, significantly reducing the effective rod length. Excessive core non-roundness is particularly severe for small-core-diameter core rods, such as those for non-zero dispersion optical fibers, and can easily cause fiber geometry parameters or PMD to exceed specified limits. The production process for these non-zero dispersion-shifted single-mode optical fiber core rods requires not only precise control of the deposition of each core layer but also quality control during the core melting and melting process. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to address the deficiencies in the above-mentioned prior art and propose a method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform rod, as well as the preform rod and optical fiber obtained. It can not only ensure the deposition processing accuracy, but also improve the quality of the core rod melting process, thereby realizing the precise manufacturing of the core rod and further optimizing the optical fiber performance.

[0005] The manufacturing method and technical solution adopted by the present invention to solve the above-mentioned problems are as follows: Depositing the inner cladding and core layer, using a quartz liner tube through the PCVD process to deposit the inner cladding and multi-layer core layer of the non-zero dispersion shifted optical fiber preform core rod in the tube, the multi-layer core layer is 2 to 4 layers, the relative refractive index difference of the multi-layer core layer decreases layer by layer, the relative refractive index difference is 0.2 to 0.7%, and the core diameter range is 4 to 10 mm, The core rod is made by melting and shrinking. The deposited tube with the inner cladding and core layer deposited is heated and shrunk in a melting and shrinking lathe to form a core rod containing the core layer and the inner cladding as one. The outer diameter and out-of-roundness of the core rod are adjusted by controlling the axial movement speed and output power of the heating furnace during the heating and shrinking process. To make an optical fiber preform, a core rod is spray-deposited with a pure silica outer cladding through an OVD process, or a core rod is covered with a pure silica outer sleeve, and then sintered or melted to make a non-zero dispersion-shifted optical fiber preform.

[0006] According to the above scheme, the heating and shrinking process is to add rod diameter measuring instruments on both sides of the heating furnace of the shrinking lathe, and pressure sensors are provided at both ends of the shrinking deposition tube. The deposition tube is installed on the lathe, and the heating furnace is moved while rotating. Through 2 to 6 shrinking passes, the rod diameter is gradually reduced and the rod diameter is kept uniform until the shrinking pass obtains a suitable and uniform center aperture. The last pass is the sintering pass. While each shrinking pass, the change in rod diameter before and after shrinking is measured to form an axial distribution curve of the rod diameter for each pass. At the same time, the shrinking pressure is recorded and controlled to match it with the rod diameter. Then, the power and speed of the heating furnace are dynamically adjusted, and the pressure is controlled to avoid the gas line problem and effectively improve the out-of-roundness.

[0007] According to the above plan, the power of the heating furnace for subsequent melting and shrinking is adjusted based on the difference between the average value and the target value of the middle area of ​​the deposited tube rod diameter. According to the local change of the rod diameter, the speed of the heating furnace at the corresponding position of the next trip is adjusted to ensure uniform melting and shrinkage of the rod diameter.

[0008] According to the above scheme, the core roundness of the preform core rod is improved based on the matching of the rod diameter and the melt shrinkage pressure.

[0009] According to the above scheme, the heating furnace temperature is controlled between 1600°C and 2200°C, the heating furnace moves axially at a speed of 10 to 30 mm / min during the melting, shrinking and sintering phase, and the deposition tube rotates at a speed of 15 to 35 rad / min. The heating furnace is a graphite resistance heating furnace or an induction furnace, with an axial heating area of ​​100 to 350 mm. The circumferential gap between the heating furnace jacket and the deposition tube is filled with a protective gas. The protective gas is an inert gas such as Ar or He.

[0010] According to the above scheme, the relative pressure (relative to atmospheric pressure) of the melting trip is controlled in the range of ±30 Pa, and the relative pressure of the sintering trip is controlled in the range of -500 Pa ~ -990 Pa.

[0011] According to the above scheme, the quartz liner tube is a doped quartz glass tube with a wall thickness of 6~9mm. The relative refractive index difference is gradually distributed, high inside and low outside, and convex upward. The relative refractive index difference of the inner surface of the sleeve (inner edge of the inner cladding) is 0.1~0.2%, and the relative refractive index difference of the outer surface (outer edge of the inner cladding) is -0.2~0%.

[0012] According to the above solution, the outer cladding wall thickness of the optical fiber preform is 35-60 mm.

[0013] According to the above scheme, the optical fiber preform core rod has three core layers. The first core layer (outermost layer) has a relative refractive index difference Δn1 of 0.15-0.25% and a diameter of 7-9 mm. The second core layer (middle layer) has a relative refractive index difference Δn2 of 0.34-0.45% and a diameter of 5-7 mm. The third core layer (innermost layer) has a relative refractive index difference Δn3 of 0.5-0.6% and a diameter of 3-5 mm.

[0014] According to the above solution, the optical fiber preform core rod has two inner cladding layers, the relative refractive index difference Δn4 of the first inner cladding layer is -0.1~0%, the diameter is 15~17 mm, and the second inner cladding layer is composed of a quartz liner tube.

[0015] According to the above solution, the core non-circularity of the optical fiber preform core rod is typically 0.4%.

[0016] The non-zero dispersion-shifted optical fiber preform of the present invention is manufactured according to the above scheme, that is, it is formed by integrating a core rod and an outer cladding or a pure silica outer sleeve.

[0017] The non-zero dispersion-shifted optical fiber of the present invention is formed by drawing the optical fiber preform rod produced by the above-mentioned solution through a drawing tower.

[0018] According to the above solution, the non-zero dispersion-shifted optical fiber has an attenuation of ≤0.5dB / km in the 1383nm band, an attenuation of ≤0.195dB / km in the 1550nm band, and an attenuation of ≤0.200dB / km in the 1625nm band.

[0019] According to the above scheme, the dispersion slope of the non-zero dispersion-shifted optical fiber is ≤0.075ps / (nm²·km), the zero dispersion wavelength is ≤1520nm, the dispersion in the range of 1530nm~1565nm is 2~6ps / (nm·km), and the dispersion in the range of 1565nm~1625nm is 4.5~11.2ps / (nm·km).

[0020] According to the above scheme, the mode field diameter of the non-zero dispersion-shifted optical fiber at a wavelength of 1550nm is 9.2μm-10μm, the cabled cutoff wavelength is ≤1450nm, and the bending performance of the optical fiber is ≤0.03dB in a test of 100 turns around a diameter of 60mm.

[0021] The beneficial effects of the present invention are: 1. The PCVD process can ensure the accuracy of deposition processing, and the improvement of the core rod melting process can improve the quality of the core rod melting process, reduce the non-circularity and curvature of the core rod, thereby realizing the precise manufacturing of the core rod, and the optical fiber produced can find a better balance between dispersion-nonlinear effect-bending loss, so that the optical fiber performance is further optimized. 2. The melting process automatically corrects the fluctuation of the local rod diameter by locally adjusting the axial movement speed and output power changes, keeps the central aperture of the deposition tube uniform during the entire melting process, and controls the melting pressure at the same time. In the process of gradually reducing the rod diameter, the roundness of the deposition tube and the core roundness can be effectively maintained intact. During the sintering process, a certain pressure difference between the inside and outside of the tube is still maintained, and the relative pressure is controlled at -500~-999Pa, which can not only achieve normal sintering, but also further ensure the integrity of the core roundness. 3. The liner in the present invention adopts an upward convex gradient refractive index distribution. Since the inner cladding of the non-zero dispersion-shifted optical fiber regulates the dispersion characteristics, mode field distribution and bending loss of the optical fiber, the second inner cladding formed not only simplifies the multi-layer step structure, but also finds a better balance between dispersion-nonlinear effect-bending loss. 4. The non-zero dispersion-shifted optical fiber preform obtained has the highest refractive index core layer as the innermost layer, which is used for strong beam confinement. There are 2 to 3 stepped core layers on the outside that decrease in size step by step, which are used to fine-tune the waveguide dispersion and effective mode field diameter. The stepped core layer forms the main waveguide, and the liner forms the second inner cladding in the inner cladding. A refractive index elevation area is first formed at the first cladding to attract the mode field to gather and increase the effective area. It then gradually decreases, providing a continuous optical barrier so that the mode field can transition to the outside more smoothly, which not only ensures the increase in effective area but also has a shielding effect on bending leakage. In addition, the upward convex gradient distribution makes the change of dn / dr in the refractive index raising region smoother, and the waveguide dispersion is less dependent on the wavelength, so as to obtain a lower dispersion slope. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the radial structure of the non-zero dispersion-shifted optical fiber preform of the present invention.

[0023] Figure 2 Schematic diagram of the refractive index profile of the non-zero dispersion-shifted optical fiber of the present invention.

[0024] Figure 3 It is a structural schematic diagram of the melt-shrink lathe and the melt-shrink process of the present invention.

[0025] Figure 4 This is a comparison diagram of the out-of-roundness of the core of the present invention and the existing melt-shrink mandrel.

[0026] Figure 5 This is a comparison chart of the statistical distribution of the out-of-roundness of the core of the present invention and the existing melt-shrink mandrel.

[0027] Figure 6This is a comparison chart of the PMD of optical fibers pulled by the present invention and conventional fusion-shrinkage core rods. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0029] One embodiment of the present invention is Figures 1 to 6 As shown, a 6.5mm-thick quartz liner is used. The liner is a doped quartz glass tube with a gradient relative refractive index difference, higher inside and lower outside, forming an upwardly convex shape. The relative refractive index difference on the inner surface (inner edge of the inner cladding) is 0.2%, and on the outer surface (outer edge of the inner cladding) it is -0.1%. A cladding layer and three core layers (X1) are deposited using a PCVD process. The refractive index of the core layers decreases layer by layer, with the relative refractive index difference between the three core layers ranging from 0.3 to 0.7%. The inner cladding consists of two layers, the first inner cladding (X2) being the deposited inner cladding, and the second inner cladding (X3) being the quartz liner. After deposition, the core rod is melted and condensed in a melt-contraction device to obtain a core rod with a diameter of 29.4mm. After melt-contraction, the core rod is manufactured as a single core rod containing the core layer and inner cladding. The core rod is then spray-deposited with a pure silica outer cladding layer (X4) through the OVD process. This is then sintered to form a 55mm-thick pure silica outer cladding, creating a non-zero dispersion-shifted single-mode optical fiber preform. Alternatively, the core rod is sheathed with a pure silica outer sleeve and melt-contracted to form a 55mm-thick pure silica outer cladding, creating a complete optical fiber preform.

[0030] The shrinking process is as follows: the deposition tube 1 is mounted entirely on the shrinking and sintering lathe. Rotary chucks 7 and 8 at both ends secure the tube, ensuring it is centered in the heating furnace 2. These chucks 7 and 8 are equipped with inlet and outlet pressure gauges 5 and 6, respectively. Protective gas is drawn from the inlet chuck 7 through the deposition tube's through-hole 9 and out the outlet chuck 8. The chucks are then turned on, rotating synchronously, causing the deposition tube to rotate at a constant speed. The reciprocating motion of the heating furnace 2 outside the deposition tube 1 provides the heat source for shrinking and sintering. When the heating element temperature reaches 1900°C, the first shrinking cycle begins. Oxygen enters the deposition tube from the inlet through the rotary chuck 7, maintaining a slightly positive pressure inside the tube. After shrinking begins, as the heating furnace moves from left to right, a caliper 4 measures the rod diameter distribution of the deposition tube before shrinking, and a caliper 3 measures the rod diameter distribution after shrinking. The difference between the values ​​at the same position represents the change in rod diameter at the current speed and power. Compare the average value of the middle 50% area of ​​the diameter gauge 3 with the target diameter of the corresponding trip. If the diameter is larger (smaller) than the target diameter, the heating furnace power will be increased (or decreased) accordingly during the return trip (when the heating furnace moves from right to left) to bring the diameter of the rods in the next trip closer to the target diameter. This automatically corrects the heating power. If the diameter gauge 3 is larger (or smaller) at 790-810mm during the first trip, the heating furnace travel speed will be reduced (or increased) in the area near 790-810mm during the second trip to correct the local rod diameter difference and achieve uniform rod diameter. The power automatic regulation correction calculation method is: The power Pn of the nth melting and shrinking is calculated as follows: P n =P n-1 +P mm *(D n-1目标 –D n实际 ) / (D n-1目标 –D n目标 ), (n≥2) Where: P n : heating furnace power of the nth pass, kw; P mm : Power correction factor (determined according to different types of core rods), kw; D n目标 : target value of rod diameter for the nth pass, mm; D n实际 : The measured value of the rod diameter at the nth pass, mm; Example: When n=2, P1 is 15kw, P mm is 0.6kw, if the first target rod diameter D 1目标 The target rod diameter for the second pass is 36 mm. 2目标 is 34.5 mm, and the actual rod diameter D of the second pass after the first pass is 2实际 35mm, the second power can be calculated P2=15+0.6*(36-35) / (36-34.5)=15.2kw The calculation method for automatic speed adjustment is: Taking the maximum variable diameter of 800mm as the center, the velocity increment is superimposed in the nearby area and calculated as follows: Vmax = VN + Vmm*(D avg -DT) Where: VN: Original set speed, mm / min V mm : Speed ​​correction factor (depending on the type of mandrel), mm / min D avg : Average rod diameter, mm DT: local rod diameter extreme value, mm Example: When the original set speed VN is 25mm / min, the average rod diameter D avg 34.5mm, the local rod diameter extreme value DT at 800mm is 35.5mm, if Vmm is 3.0kw, the maximum change speed is calculated as Vmax = 25+3.0*(34.5-35.5)= 22 mm / min That is, the heating furnace begins uniform deceleration at the position 800-100 (RL) = 700. From 700mm to 800mm, the speed decreases from 25mm / min to 22mm / min. It then begins uniform acceleration, increasing to 25mm / min within the 50mm (RR) mm range, i.e., from 800-850mm. RL is the left-shifting speed range, and RR is the right-shifting speed range.

[0031] The core rod obtained by the melt-contraction method of the present invention can significantly improve the core layer out-of-roundness, and its typical value can be reduced from 1.2% to below 0.4% ( Figure 5 Under the same drawing conditions, the polarization mode dispersion of the drawn optical fiber can be reduced by about 25% ( Figure 6 ) The preform produced in this embodiment was drawn into a fiber using a drawing tower at a drawing speed of 1500 m / min. The resulting non-zero dispersion-shifted optical fiber had the following parameters: the first core layer had a relative refractive index difference Δn1 of 0.18% and a diameter of 6.3 μm; the second core layer had a relative refractive index difference Δn2 of 0.44% and a diameter of 5.2 μm; and the third core layer had a relative refractive index difference Δn3 of 0.58% and a diameter of 4.3 μm. The first inner cladding had a relative refractive index difference Δn4 of -0.15% and a diameter of 12.6 μm. The second inner cladding had an inner surface relative refractive index difference Δn5 of 0.2% and an outer surface relative refractive index difference Δn6 of -0.1% with a diameter of 24.1 μm. The outer cladding was pure silica glass. The optical fiber has an attenuation of 0.349 dB / km in the 1383 nm band, 0.193 dB / km in the 1550 nm band, and 0.199 dB / km in the 1625 nm band. The dispersion slope is 0.0717 ps / (nm²·km), the zero dispersion wavelength is 1484 nm, the dispersion in the range of 1530 nm to 1565 nm is 3.23 to 5.74 ps / (nm·km), and the dispersion in the range of 1565 nm to 1625 nm is 5.74 to 10 ps / (nm·km). The mode field diameter at a wavelength of 1550 nm is 9.37 μm, the cabled cutoff wavelength is 1288 nm, and the bending performance of the optical fiber is tested. In a test of 100 turns around a 60 mm diameter, the bending loss is 0.011 dB.

Claims

1. A method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform, characterized in that Depositing inner cladding and core layer, using a quartz liner tube through PCVD process to deposit multi-layer inner cladding and multi-layer core layer of non-zero dispersion shifted optical fiber preform core rod in the tube, the multi-layer core layer is 2 to 4 layers, the relative refractive index difference of the multi-layer core layer decreases layer by layer, the relative refractive index difference is 0.2 to 0.7%, and the core diameter range is 4 to 10 mm, The core rod is made by melting and shrinking. The deposited tube with the inner cladding and core layer deposited is heated and shrunk in a melting and shrinking lathe to form a core rod containing the core layer and the inner cladding as one. The outer diameter and out-of-roundness of the core rod are adjusted by controlling the axial movement speed and output power of the heating furnace during the heating and shrinking process. To make an optical fiber preform, a core rod is spray-deposited with a pure silica outer cladding through an OVD process, or a core rod is covered with a pure silica outer sleeve, and then sintered or melted to make a non-zero dispersion-shifted optical fiber preform.

2. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 1, characterized in that The heating and shrinking process is to add rod diameter measuring instruments on both sides of the heating furnace of the shrinking lathe, and pressure sensors are provided at both ends of the shrinking deposition tube. The deposition tube is installed on the lathe, and the heating furnace is moved while rotating. Through 2 to 6 shrinking passes, the rod diameter is gradually reduced and the rod diameter is kept uniform until the aperture pass obtains a suitable and uniform central aperture. The last pass is the sintering pass. During each shrinking pass, the change in rod diameter before and after shrinking is measured to form an axial distribution curve of the rod diameter for each pass. At the same time, the shrinking pressure is recorded and controlled to match it with the rod diameter. Then, the power and speed of the heating furnace are dynamically adjusted, and the pressure is controlled to effectively improve the out-of-roundness on the basis of avoiding the gas line problem.

3. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 2, wherein According to the difference between the average value of the middle area of ​​the deposited tube rod diameter and the target value, the heating furnace power of the subsequent melting and shrinking trip is adjusted. According to the local change of the rod diameter, the heating furnace speed of the corresponding position of the next trip is adjusted to ensure uniform melting and shrinkage of the rod diameter.

4. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 3, wherein According to the matching of rod diameter and melt shrinkage pressure, the core roundness of the preform core rod is improved.

5. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 2 or 3, characterized in that The temperature of the heating furnace is controlled at 1600°C~2200°C, the speed of the heating furnace moving axially during the melting, shrinking and sintering phase is 10~30mm / min, and the rotation speed of the deposition tube is 15~35 rad / min; the heating furnace is a graphite resistance heating furnace or an induction furnace, the axial heating area is 100~350mm, and the circumferential gap between the heating furnace jacket and the deposition tube is filled with protective gas.

6. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 2 or 3, characterized in that The relative pressure of the melting trip is controlled within the range of ±30 Pa, and the relative pressure of the sintering trip is controlled within the range of -500 Pa to -990 Pa.

7. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 1 or 2, characterized in that The quartz liner tube is a doped quartz glass tube with a wall thickness of 6~9mm. The relative refractive index difference is gradually distributed, high inside and low outside, and convex. The relative refractive index difference of the inner surface of the sleeve is 0.1~0.2%, and the relative refractive index difference of the outer surface is -0.2~0%.

8. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 1 or 2, characterized in that The outer cladding wall thickness of the optical fiber preform is 35-60 mm.

9. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 1 or 2, characterized in that The optical fiber preform core rod has three core layers. The relative refractive index difference Δn1 of the first core layer is 0.15-0.25%, and the diameter is 7-9 mm. The relative refractive index difference Δn2 of the second core layer is 0.34-0.45%, and the diameter is 5-7 mm. The relative refractive index difference Δn3 of the third core layer is 0.5-0.6%, and the diameter is 3-5 mm.

10. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 9, wherein The optical fiber preform core rod has two inner cladding layers, the relative refractive index difference Δn4 of the first inner cladding layer is -0.1-0%, the diameter is 15-17 mm, and the second inner cladding layer is composed of a quartz liner tube.

11. The method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to claim 1 or 2, characterized in that The core out-of-roundness of the optical fiber preform core rod is typically 0.4%.

12. A non-zero dispersion-shifted single-mode optical fiber preform, characterized in that The non-zero dispersion-shifted single-mode optical fiber preform is manufactured according to the method for manufacturing a non-zero dispersion-shifted single-mode optical fiber preform according to any one of claims 1-11.

13. A non-zero dispersion-shifted single-mode optical fiber, characterized in that The non-zero dispersion-shifted single-mode optical fiber is made by drawing the non-zero dispersion-shifted single-mode optical fiber preform according to claim 12.

14. The non-zero dispersion-shifted single-mode optical fiber according to claim 13, characterized in that The optical fiber has an attenuation of ≤0.5dB / km in the 1383nm band, an attenuation of ≤0.195dB / km in the 1550nm band, and an attenuation of ≤0.200dB / km in the 1625nm band.

15. The non-zero dispersion-shifted single-mode optical fiber according to claim 13, characterized in that The non-zero dispersion-shifted optical fiber has a dispersion slope of ≤0.075 ps / (nm²·km), a zero dispersion wavelength of ≤1520 nm, a dispersion of 2 to 6 ps / (nm·km) in the range of 1530 nm to 1565 nm, and a dispersion of 4.5 to 11.2 ps / (nm·km) in the range of 1565 nm to 1625 nm.

16. The non-zero dispersion-shifted single-mode optical fiber according to claim 13, characterized in that The non-zero dispersion-shifted optical fiber has a mode field diameter of 9.2 μm-10 μm at a wavelength of 1550 nm, a cabled cutoff wavelength of ≤1450 nm, and a bending loss of ≤0.03 dB in a test of 100 turns of the optical fiber with a diameter of 60 mm.

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