Ultra-low loss optical fiber preparation method and corresponding optical fiber

Abstract

The invention provides a preparation method of an ultralow-loss optical fiber, which realizes uniform doping of alkali metal by optimizing a doping process. And meanwhile, the cladding adopts an F-doped technology to reduce the refractive index and optimize the wire drawing process, and finally, the development of ultralow-loss low-water-peak large-effective-area optical fiber products is realized. An optical fiber preform is manufactured in advance, and then the optical fiber preform is drawn to form an optical fiber. The method is characterized in that the manufacturing method of the opticalfiber preform comprises the following steps that: the core rod is prepared in advance through a VAD method; alkali metal neutral salt is used as a raw material in the preparation process of the ultralow-loss alkali-metal-doped optical fiber; an oxygen-enriched carrier gas is introduced into a sintering furnace core tube for alkali metal doping, the temperature in the doping process is controlledto be within the range of 1000-1800 DEG C, the doping time is controlled to be 2-6 hours, and an alkali metal doped core layer is prepared; and by washing the alkali metal doped core layer with hydrofluoric acid for 5-24 hours, the alkali metal doping concentration is 20-200 ppm.

Description

technical field [0001] The invention relates to the technical field of optical fiber technology, in particular to a method for preparing an ultra-low loss optical fiber, and the invention also provides the ultra-low loss optical fiber. Background technique [0002] With the continuous improvement of wired and wireless access bandwidth, the rapid development of technologies such as mobile Internet, cloud computing, and big data, the demand for global bandwidth is exploding. 400G will be the direction for the construction and upgrade of the next-generation backbone network in the future. In the 400G and 1T era, fiber attenuation and nonlinear effects have become the main factors restricting the improvement of system transmission performance. The receiving end adopts coherent reception and digital signal processing technology (DSP), which can digitally compensate the dispersion accumulated in the entire transmission process in the electrical domain. and polarization mode disper...

AI Technical Summary

Problems solved by technology

At present, MCVD and PCVD have the characteristics of good doping uniformity, but it is difficult to remove the hydroxyl group introduced during the preparation process, resulting in a water peak exceeding 0.5dB. VAD can prepare ultra-low loss optical fibers with low water peaks, but the doping uniformity is poor, and it is easy to cause crystallization during doping

Images