US 11,754,777 B2
Low-crosstalk large-capacity few-mode optical fiber
Shuguang Li, Qinhuangdao (CN); Pengshuai Shao, Qinhuangdao (CN); Jianshe Li, Qinhuangdao (CN); Ying Guo, Qinhuangdao (CN); and Xiaojian Meng, Qinhuangdao (CN)
Assigned to Yanshan University, Qinhuangdao (CN)
Filed by Yanshan University, Qinhuangdao (CN)
Filed on Jul. 14, 2022, as Appl. No. 17/864,425.
Claims priority of application No. 202110975835.9 (CN), filed on Aug. 24, 2021.
Prior Publication US 2023/0064605 A1, Mar. 2, 2023
Int. Cl. G02B 6/02 (2006.01); G02B 6/036 (2006.01)
CPC G02B 6/02042 (2013.01) [G02B 6/03611 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A low-crosstalk large-capacity few-mode optical fiber, comprising an optical fiber cladding, wherein few-mode units are arranged in the optical fiber cladding, each of the few-mode units sequentially comprises a few-mode fiber core, an inner cladding and a trench from inside to outside, and a high-refractive-index ring is arranged in the few-mode fiber core; the few-mode units comprise first few-mode subunits, second few-mode subunits and third few-mode subunits, wherein the first few-mode subunits, the second few-mode subunits and the third few-mode subunits are arranged at intervals; and
each of the first few-mode subunits comprises a first few-mode fiber core, each of the second few-mode subunits comprises a second few-mode fiber core, and each of the third few-mode subunits comprises a third few-mode fiber core, wherein radii of the first few-mode fiber cores, the second few-mode fiber cores and the third few-mode fiber cores are different, and refractive indexes of the first few-mode fiber cores, the second few-mode fiber cores and the third few-mode fiber cores are different;
wherein the optical fiber cladding is made of a silica material, the inner cladding is made of a silica material, the trench is made of a silica material doped with fluorine, the few-mode fiber core is made of a silica material doped with germanium dioxide, and the high-refractive-index ring is made of a silica material doped with high-concentration germanium dioxide;
wherein the few-mode units have a step-type distribution design in refractive indexes;
wherein the optical fiber cladding has a refractive index of n0, the inner cladding has a refractive index of n0, the trench has a refractive index of n3, the first few-mode fiber core has a refractive index of n1, the second few-mode fiber core has a refractive index of n4, and the third few-mode fiber core has a refractive index of n6;
each of the first few-mode subunits comprises a first high-refractive-index ring, each of the second few-mode subunits comprises a second high-refractive-index ring, and each of the third few-mode subunits comprises a third high-refractive-index ring, wherein the first high-refractive-index ring has a refractive index of n2, the second high-refractive-index ring has a refractive index of n5, and the third high-refractive-index ring has a refractive index of n7 and
the n1 is greater than the n0, the n2 is greater than the n1, the n3 is less than the n0, the n4 is greater than the n0, the n5 is greater than the n4, the n6 is greater than the n0, and the n7 is greater than the n6.