Single-mode optical fiber with low attenuation and large effective area

Abstract

The invention relates to a single-mode optical fiber with low attenuation and large effective area. The single-mode optical fiber comprises a core layer and a wrapping layer, and is characterized in that the core layer comprises a sunken inner core layer and an outer core layer, the radius r1 of the sunken inner core layer is 2.2 - 3.5 microns, delta n1 is 0. 08% - 0. 20%, the radius r2 of the outer core layer is 5 -6.5 microns, delta n2 is 0.20%-0.32%, the wrapping layer wraps outside the core layer, the wrapping layer sequentially comprises an inner wrapping layer, a sunken wrapping layer and an outer wrapping layer from inside to outside, the radius r3 of the inner wrapping layer is 9 -13 microns, delta n3 is -0.06% -0.06%, the radius r4 of the sunken wrapping layer is 11-18 microns, and the delta n4 is -0.60%- -0.35%; and the outer wrapping layer is a pure silicon dioxide glass layer. A sunken structure of the central core layer is arranged, so that the internal energy distributionof an optical fiber is changed from the typical gaussian distribution to the non-gaussian distribution, and the effective area of the optical fiber is effectively increased on the basis that the cut-off wavelength and the dispersion performance of the optical fiber are ensured. The optical fiber is low in attenuation and large in effective area. The optical fiber is low in manufacturing cost andhas relatively good bending loss and dispersion performance.

Description

Technical field [0001] The invention relates to the field of optical fiber transmission, in particular to a single-mode optical fiber with low attenuation and large effective area, which is used in a long-distance, large-capacity, and high-speed transmission system. Background technique [0002] With the emergence of coherent transmission technology, in the field of optical fiber transmission, some important indicators that originally restricted long-distance, large-capacity, and high-speed transmission no longer become restrictions. In the future transmission system, chromatic dispersion (CD) and polarization mode dispersion ( PMD) indicators can be further relaxed. However, the attenuation and effective area of ​​optical fibers are still important issues that limit the development of optical communication technology. [0003] Especially in the future transmission system of 400G or higher, the reduction of attenuation will greatly reduce the construction and maintenance cost of t...

AI Technical Summary

Problems solved by technology

However, because of the conventional fluorine outer cladding design, the core layer is still relatively viscous than the fluorine outer cladding, and defects are still prone to occur during the wire drawing process, which limits the further reduction of fiber attenuation performance. In addition, the fluorine outer cladding structure is adopted. Due to the fluorine The cost of doping is high, and the viscosity is very low. In the process of preparing and drawing optical fiber preforms, the preparation process of preforms with pure silica outer cladding is more complicated, the process control progress is higher, and the cost is higher.

Images