| 摘要 |
An optical fiber includes a silica-based glass portion having an outer diameter of less than about 120 mum. The glass portion comprises a core, an inner cladding and a low index ring. The core comprises an index of refraction n1, and a relative refractive index percent Delta1% relative to pure silica glass. The inner cladding surrounds the core and comprises an index of refraction n2, a radial thickness of less than about 40 mum and a relative refractive index percent Delta2% relative to pure silica glass, wherein Delta1%>Delta2% and the difference between Delta1% and Delta2% is greater than 0.1%. The low index ring surrounds the inner cladding and comprises boron and fluorine, a radial thickness of less than about 20 mum, an index of refraction n3 and a third relative refractive index percent Delta3% relative to pure silica glass, wherein Delta2%>Delta3% and Delta3% is less than -0.5%. |
