Rare earth doped and large effective area optical fibers for fiber lasers and amplifiers
AssigneeImra America, Inc.
InventorsLiang Dong, Xiang Peng
Life of this patent
Estimating the term…
Abstract
Various embodiments described herein include rare earth doped glass compositions that may be used in optical fiber and rods having large core sizes. Such optical fibers and rods may be employed in fiber lasers and amplifiers. The index of refraction of the glass may be substantially uniform and may be close to that of silica in some embodiments. Possible advantages to such features include reduction of formation of additional waveguides within the core, which becomes increasingly a problem with larger core sizes.
Claims35
A step index optical fiber comprising:
- a core having a core radius ρ;
- a first cladding disposed about said core;
- and
- a second cladding disposed about said first cladding, said first cladding having an outer radius ρ1, said core and said first cladding having a difference in index of refraction Δn, and said first cladding and said second cladding having a difference in index of refraction Δn1,
- wherein (i) less than 10 modes are supported in said core, (ii) the first cladding radius, ρ1, is greater than about 1.1ρ and less than about 2ρ, and (iii) the refractive index difference between said first cladding and said second cladding, Δn1, is greater than about 1.5Δn and less than about 50Δn.
A large-core optical fiber comprising:
- a core having a core radius p and a core index of refraction ncore;
- a first cladding disposed about said core, said first cladding having an outer radius ρ1 and an index of refraction nc1, said core and said first cladding having a difference in index of refraction Δn=ncore−nc1, and a numerical aperture (NA) less than about 0.05, said NA determined by ncore and nc1;
- and
- a second cladding disposed about said first cladding, said first cladding and said second cladding having a difference in index of refraction Δn1,
- wherein the first cladding radius, ρ1, is greater than about 1.1ρ and less than about 2ρ, and the refractive index difference between said first cladding and said second cladding, Δn1, is greater than about 1.5Δn and less than about 50Δn.
A large-core optical fiber comprising:
- a core having a core radius ρ and a core index of refraction ncore, and having substantial refractive index uniformity over said core;
- a first cladding disposed about said core, said first cladding having an outer radius ρ1, said core and said first cladding having a difference in index of refraction Δn;
- and
- a second cladding disposed about said first cladding, said first cladding and said second cladding having a difference in index of refraction Δn1,
- wherein the first cladding radius, ρ1, is greater than about 1.1ρ and less than about 2ρ, and the refractive index difference between said first cladding and said second cladding, Δn1, is greater than about 1.5Δn and less than about 50Δn.
Dependencies are inferred from the claim text.