Ultralow-attenuation and large-effective-area single-mode fiber

Abstract

The invention relates to an ultralow-attenuation and large-effective-area single-mode fiber comprising a core layer and wrapping layers. The ultralow-attenuation and large-effective-area single-mode fiber is characterized in that the radius r1 of the core layer is 5-8 microns, the relative refractive index deltan1 of the core layer is 0-0.20%, and the core layer wraps an internal wrapping layer, a recessed internal wrapping layer and an external wrapping layer from inside to outside in turn. The radius r2 of the internal wrapping layer is 8.5-12 microns, and the relative refractive index deltan2 is -0.20--0.45%. The radius r3 of the recessed internal wrapping layer is 12.5-30 microns, and the relative refractive index deltan3 is -0.40--0.65%. The external wrapping layer is a fully fluoridated silicon dioxide glass layer, and the relative refractive index deltan4 is -0.22--0.53%. The ultralow-attenuation and large-effective-area single-mode fiber has the specific viscosity matching design: the core layer is not the pure silicon core and has the characteristics of co-doping of germanium and fluorine, and the chlorine doping technology is also performed so that the fiber viscosity can be reduced and the structural relaxation of glass can be accelerated; and the core layer viscosity matching is optimized by controlling the doping concentration, and the viscosity of each part of the fiber and the fiber strain are optimized so that ultralow-attenuation performance of the single-mode fiber can be realized.

Description

technical field [0001] The invention relates to the field of optical communication, in particular to a single-mode optical fiber with ultra-low attenuation and large effective area. Background technique [0002] At present, the hot spot in the field of optical fiber manufacturing is the preparation of new ultra-low attenuation single-mode optical fiber products, so finding an effective method to reduce the attenuation coefficient of optical fiber and control manufacturing costs is a huge challenge for optical fiber manufacturing enterprises. The main difficulty lies in the following three points: First, how to reduce the attenuation: the main method at present is to reduce the Rayleigh scattering coefficient of the optical fiber; second, while obtaining an ultra-low attenuation coefficient, it is necessary to ensure that the optical parameters of the optical fiber meet the requirements of the ITU-T The standard mainly refers to the control of MFD, dispersion, cut-off wavelen...

AI Technical Summary

Problems solved by technology

Simply put, if germanium-fluorine co-doping is not used in the core layer, the viscosity of the core layer will be significantly greater than that of the inner cladding layer, and the structural relaxation time τ of the core layer core will be much longer than the relaxation time τ of the inner cladding structure clad , resulting in a stress mismatch at the center of the core layer during the fiber drawing process, more defects appear at the interface between the core layer and the inner cladding layer, and the attenuation coefficient increases

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