Low-attenuation bend-insensitive single-mode fiber

Abstract

The invention relates to a low-attenuation bend-insensitive single-mode fiber, which is used in a fiber communication system and comprises a core layer and three claddings. The low-attenuation bend-insensitive single-mode fiber is characterized in that the relative refractive index difference delta1 of the core layer ranges from 0.1% to 0.30%, the radius R1 of the core layer ranges from 3.5 micrometers to 4.5 micrometers, the three claddings are arranged on the outside of the core layer, the first cladding is an inner cladding tightly encircling the core layer, the relative refractive index difference delta2 of the inner cladding ranges from -0.1% to 0.1%, the radius R2 of the inner cladding ranges from 8 micrometers to 10 micrometers, the second cladding is a depressed cladding tightly encircling the inner cladding, the relative refractive index difference delta3 of the depressed cladding ranges from -0.4% to -0.1%, the delta3 is smaller than the delta2, the radius R3 of the depressed cladding ranges from 12 micrometers to 20 micrometers, the third cladding is an outer cladding tightly encircling all sub-claddings of the depressed cladding, and the relative refractive index difference delta4 of the outer cladding ranges from -0.2% to 0.1%. On the basis of comprehensive compatibility to existing G.652 standards, the low-attenuation bend-insensitive single-mode fiber has an attenuation performance far superior to that of a conventional G.652.D fiber, the microscopic bending requirement of G.657.A1 standards can be met, and application of a dense wavelength division multiplexing system is facilitated.

Description

Technical field [0001] The invention relates to a low-attenuation bending-insensitive single-mode optical fiber used in an optical fiber communication system. The optical fiber has improved bending resistance and lower optical fiber loss, and belongs to the technical field of optical communication. Background technique [0002] At present, in the field of optical fiber communication, two types of optical fibers are mainly used, single-mode optical fiber and multi-mode optical fiber. Compared with multi-mode fiber, single-mode fiber has the advantages of fast transmission rate, large information carrying capacity, and long transmission distance. It is widely used in the construction of optical fiber communication networks. Among them, the fiber that meets the ITU-T G.652 standard It is also the most widely used fiber in single-mode fiber. With the continuous development of FTTx in recent years, the performance of the original G.652 fiber can no longer meet user requirements, an...

AI Technical Summary

Problems solved by technology

However, the reduction of the mode field diameter will result in a reduction of the effective area, and it is easier to cause more defects and increase the attenuation during wire drawing. At the same time, the cut-off wavelength of the fiber must be smaller than the working wavelength to ensure the single-mode working characteristics, so There is limited space to improve the bending performance of the fiber by changing the MAC value of the fiber

The second is that the bending performance can be improved by using a double-clad structure in which the inner cladding is a depressed cladding, but the depressed cladding may cause the "LP01 mode leakage" phenomenon of the optical fiber

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