Alkali and fluorine doped optical fiber
AssigneeCorning Incorporated
InventorSnigdharaj Kumar Mishra
Life of this patent
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Abstract
Disclosed is an optical fiber having a core of SiO2 doped with fluorine and an alkali metal oxide dopant. The alkali metal oxide is selected from the group consisting of K, Na, Li, Cs and Rb and is provided in amount of at least 20 ppm wt. %. The fiber has an inner cladding surrounding the core, which also includes fluorine. A relative refractive index of the inner cladding (Δ2%), measured relative to pure silica, is preferably between −0.39% and −0.7%. The fiber preferably exhibits attenuation at 1550 nm of less than or equal to 0.178 dB/km.
Claims20
An optical fiber, comprising:
- a core including SiO2, fluorine, and an alkali metal oxide selected from the group consisting of K, Na, Li, Cs and Rb and mixtures thereof, said alkali metal oxide provided in amount of at least 20 ppm wt. %, said core having a core relative refractive index (Δ1%) measured at 2 microns offset from a fiber centerline, and
- a cladding including an inner cladding surrounding the core including fluorine, said inner cladding having a inner cladding relative refractive index (Δ2%) measured relative to pure silica between −0.39% and −0.7%.
An optical fiber, comprising:
- core containing
- SiO2,
- an alkali metal oxide selected from the group consisting of K, Na, Li, Cs and Rb and mixtures thereof,
- fluorine in an amount of between 0.1 and 0.4 wt. %, and
- chlorine in an amount of less than 500 ppm wt. %,
- said core having a core relative refractive index (Δ1%), measured at 2.0 microns offset from a fiber centerline, of between 0.0% and −0.15%, and a cladding including an inner cladding surrounding the core and including fluorine, said inner cladding having a cladding relative refractive index (Δ2%) measured relative to pure silica of between −0.39% and −0.7%.
An optical fiber, comprising:
- a core including SiO2, fluorine, chlorine, and an alkali metal oxide selected from the group consisting of K, Na, Li, Cs and Rb and mixtures thereof, said core having a core relative refractive index (Δ1%) measured at 2.0 microns offset from a fiber centerline of between 0.0% and −0.15%, an outer radius (R1) of between 3.9 to 6.0 μm, and an α profile having an α value of between 12 and 20, and
- a cladding, including an inner cladding surrounding the core, said inner cladding including fluorine and having a cladding relative refractive index (Δ2%) measured relative to pure silica of between −0.39% and −0.7%
- wherein a refractive index profile of the optical fiber is selected to provide
- dispersion at 1550 nm between 15 and 25 ps/nm/km,
- dispersion slope at 1550 nm of less than 0.07 ps/nm2/km,
- effective area at 1550 nm of greater than 60 μm2, and
- attenuation at 1550 nm of less than 0.178 dB.
Dependencies are inferred from the claim text.