DOUBLE CLAD OPTICAL FIBER WITH RARE EARTH METAL DOPED GLASS CORE

摘要

An optical fiber comprising: (i) a silica based, rare earth doped core having a first index of refraction n₁; (ii) a silica based inner cladding surrounding the core having a second index of refraction n₂, such that n₁>n₂; (iii) a silica based outer cladding surrounding the inner cladding having a third index of refraction n₃ such that n₂>n₃, wherein inner cladding diameter is at least 125 mum.