摘要:
A method of manufacturing an optical fibre preform comprising: providing a glass core rod comprising a central core region of radius a and an inner clad region of external radius b to define a first core-to-clad ratio a/b; forming an intermediate glass preform comprising an intermediate clad region surrounding the inner clad region of the glass rod and having an external radius c to define a second core-to-clad ratio a/c, and overcladding the intermediate glass preform by forming an overclad region surrounding the intermediate clad region to form an optical fibre preform, wherein the first core-to-clad ratio a/b is equal to or less than 0.40 and the second core-to-clad ratio a/c is of from 0.20 to 0.25.
摘要:
A multicore fiber includes a plurality of unit multicore fibers including a plurality of core portions and a clad portion which is formed in an outer circumference of the core portions and has a refractive index lower than a maximum refractive index of the core portions, the plurality of the core portions having substantially the same refractive index profile and different group delays at the same wavelength in the same propagation mode, wherein the core portions of the multicore fiber are configured so that the core portions of the plurality of the unit multicore fibers are connected in cascade, a maximum value of differential group delays between the core portions of the multicore fiber is smaller than a reduced value of a maximum value of differential group delays between the core portions of each unit multicore fiber as a value in terms of a length of the multicore fiber.
摘要:
The present disclosure is directed to a method of making an optical fiber with improved bend performance, the optical fiber having a core and at least one cladding layer, and a chlorine content in the in the last layer of the at least one cladding layer that is greater than 500 ppm by weight. The fiber is prepared using a mixture of a carrier gas, a gaseous chlorine source material and a gaseous reducing agent during the sintering of the last or outermost layer of the at least one cladding layer. The inclusion of the reducing gas into a mixture of the carrier gas and gaseous chlorine material reduces oxygen-rich defects that results in at least a 20% reduction in TTP during hydrogen aging testing.
摘要:
Provided is an optical fiber having W-shaped refractive-index distribution and in which a micro-bend loss in an actual usage waveband is reduced. The optical fiber includes a core, inner cladding that surrounds the core and has a refractive index smaller than a refractive index of the core, and outer cladding that surrounds the inner cladding and has a refractive index smaller than the refractive index of the core and larger than the refractive index of the inner cladding. When a coupling coefficient between a fundamental mode and a cladding mode is denoted by C 01-CL , a coupling coefficient between the fundamental mode and a higher-order mode is denoted by C 01-11 , and a coupling coefficient between the higher-order mode and the cladding mode is denoted by C 11-CL , C total defined as C total = C 01-CL + C 01-11 C 11-CL has a minimum value at a wavelength ranging between 1520 nm and 1630 nm.
摘要:
One embodiment of the disclosure relates to a method of making an optical fiber comprising the steps of: (i) exposing a silica based preform with at least one porous glass region having soot density of r to a gas mixture comprising SiCl 4 having SiCl 4 mole fraction y SiCl4 (preferably of less than 0.03) at a doping temperature T dop such that parameter X is larger than 0.03 to form the chlorine treated preform, wherein X is defined as a function of density r, doping temperature T dop , SiCl4 mole fraction y SiCl4 , and the density p s of the fully densified soot layer; and (ii) exposing the chlorine treated preform to temperatures above 1400 °C to completely sinter the preform to produce sintered optical fiber preform with a chlorine doped region; and (iii) drawing an optical fiber from the sintered optical preform.