Low-loss large-effective-area fiber and preparation technology therefor

Abstract

The invention relates to a low-loss large-effective-area fiber and a preparation technology therefor. The low-loss large-effective-area fiber comprises a core layer, wrapping layers and coating layers from inside to outside in sequence. The core layer is a pure silica glass layer with the radius of 5-7 [mu]m. An inner wrapping layer is a fluorine-doped inner wrapping layer with the radius r2 of 5-12 [mu]m and the relative refractive index difference of from -0.4% to -0.2%. The radius r3 of a middle wrapping layer is 12-25 [mu]m. An outer layer is a pure quartz glass layer with the radius r4 of 25-45 [mu]m. The coating layers adopt polyacrylate and comprise an inner coating layer and an outer coating layer, the diameter of the inner coating layer is 192 [mu]m, and the diameter of the outer coating layer is 245 [mu]m. The preparation technology comprises a perform rod preparation process, a fiber fusion annealing process and a fiber drawing and curing process. The fiber provided by the invention is advantaged in that comprehensive properties such as cut-off wavelength, bending loss and dispersion are good in an application waveband; the fiber can be used in long-distance fiber communication by crossing bad conditions of gobi, deep sea and the like; the roundness of each layer of the fiber is good, so that the appearance is enabled to be round; and the strain of the fiber can reach 2% or more.

Description

technical field [0001] The invention relates to the field of optical fibers, in particular to an ultra-low loss large effective area optical fiber and a preparation process thereof. Background technique [0002] Optical fiber strength is one of the key indicators of ultra-low loss optical fiber, which is mainly reflected in the screening strain. The strain of ordinary optical fiber is generally about 1% to deal with the tension caused by laying and thermal expansion and contraction, while ultra-low loss optical fiber is used in ultra-long In distance optical communication links, it is often necessary to cross harsh environments such as Gobi and deep sea. When considering laying or environmental temperature changes, the tension suffered is greater than that of ordinary optical cables. Considering the national standard of "Deep Sea Optical Cable", the difficulty of laying and In terms of service life, etc., it is hoped that the strain of the ultra-low loss optical fiber will r...

AI Technical Summary

Problems solved by technology

The impurity particles adhere to the surface of the optical fiber. During the cooling process, cracks and stress concentration are formed. The cracks on the optical fiber surface are gradually eroded by the action of water molecules in the atmospheric environment, resulting in the destruction of the silicon-oxygen tetrahedral structure, and the breakage of the silicon-oxygen bond will expand the microcracks. range, which affects fiber strength