REDUCED CLAD DIAMETER RARE EARTH DOPED FIBER COILS AND OPTICAL AMPLIFIERS UTILIYING SUCH COILS

摘要

According to the present invention, a rare earth doped fiber coil comprises a rare doped optical fiber having a rare-earth doped core surrounded by a cladding. The outer clad diameter is less than 100mum. The rare earth doped optical fiber has a length of 10 m to 50m and is coiled with abend radius of less than 40mm.