Abstract:
Preparation of halogen-doped silica is described. The preparation includes doping silica with high halogen concentration and sintering halogen-doped silica to a closed-pore state. The sintering includes a high pressure sintering treatment and a low pressure sintering treatment. The high pressure sintering treatment is conducted in the presence of a high partial pressure of a gas-phase halogen doping precursor and densifies a silica soot body to a partially consolidated state. The low pressure sintering treatment is conducted in the presence of a low partial pressure of gas-phase halogen doping precursor and transforms a partially consolidated silica body to a closed-pore state. The product halogen-doped silica glass exhibits little foaming when heated to form fibers in a draw process or core canes in a redraw process.
Abstract:
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.
Abstract:
An optical fiber including: (i) a silica based, Yb doped core having a first index of refraction nj, said core comprising more than lwt % of Yb, said core having less than 5 dB/km loss at a wavelength situated between 1150 run and 1350 nm and less than 20 dB/km loss at the wavelength of 1380 nm and slope efficiency of over 0.8; and (ii) at least one silica based cladding surrounding the core and having a second index of refraction n2, such that n\> n2.
Abstract translation:一种光纤,包括:(i)具有第一折射率nj的二氧化硅基Yb掺杂芯,所述芯包括大于1wt%的Yb,所述芯在波长处具有小于5dB / km的损耗,位于1150nm 1350 nm,波长1380 nm时损耗小于20 dB / km,斜率效率超过0.8; 和(ii)至少一个围绕所述芯并且具有第二折射率n2的基于二氧化硅的包层,使得n 1> n 2。
Abstract:
An optical fiber has a core region that is doped with one or more viscosity-reducing dopants in respective amounts that are configured, such that, in a Raman spectrum with a frequency shift of approximately 600 cm−1, the fiber has a nanoscale structure having an integrated D2 line defect intensity of less than 0.025. Alternatively, the core region is doped with one or more viscosity-reducing dopants in respective amounts that are configured such that the fiber has a residual axial compressive stress with a stress magnitude of more than 20 MPa and a stress radial extent between 2 and 7 times the core radius.According to another aspect of the invention a majority of the optical propagation through the fiber is supported by an identified group of fiber regions comprising the core region and one or more adjacent cladding regions. The fiber regions are doped with one or more viscosity-reducing dopants in respective amounts and radial positions that are configured to achieve viscosity matching among the fiber regions in the identified group.
Abstract:
An optical fiber having a core comprising silica and greater than 1.5 wt % chlorine and less than 0.5 wt % F, said core having a refractive index Δ1MAX, and a inner cladding region having refractive index Δ2MIN surrounding the core, where Δ1MAX>Δ2MIN.
Abstract:
An optical fiber with large effective area, low bending loss and low attenuation. The optical fiber includes a core, an inner cladding region, and an outer cladding region. The core region includes a spatially uniform updopant to minimize low Rayleigh scattering and a relative refractive index and radius configured to provide large effective area. The inner cladding region features a large trench volume to minimize bending loss. The core may be doped with Cl and the inner cladding region may be doped with F.
Abstract:
An optical fiber with large effective area, low bending loss and low attenuation. The optical fiber includes a core, an inner cladding region, and an outer cladding region. The core region includes a spatially uniform updopant to minimize low Rayleigh scattering and a relative refractive index and radius configured to provide large effective area. The inner cladding region features a large trench volume to minimize bending loss. The core may be doped with Cl and the inner cladding region may be doped with F.
Abstract:
An apparatus and method for compensating for mode-profile distortions caused by bending optical fibers having large mode areas. In various embodiments, the invention micro-structures the index of refraction in the core and surrounding areas of the inner cladding from the inner bend radius to the outer bend radius in a manner that compensates for the index changes that are otherwise induced in the index profile by the geometry and/or stresses to the fiber caused by the bending. Some embodiments of an apparatus and method include a fiber having a plurality of substantially parallel cores, the fiber including a straight section and a curved section; guiding signal light primarily in a second core in the straight section; guiding the signal light from the second core into a first core between the straight section and the curved section; and guiding the signal light primarily in the first core in the curved section.
Abstract:
According to some embodiments, the optical fiber comprises: (i) a core having a first index of refraction n1; (ii) a cladding surrounding the core and having a second index of refraction n2, such that n1>n2, wherein cladding has at two sets of stress rods extending longitudinally through the length of the optical fiber, wherein the two sets of stress rods have CTE coefficients and/or softening points different from one another and different from that of cladding.