Optical fiber assembly and light amplification coupler having rare earth doped light amplification medium and related method of making

摘要

A light amplification coupler includes a glass pipe, a first optical fiber having, at one end thereof, an input port to which signal light is inputted and having an output port at the other end thereof, the first optical fiber having an intermediate portion inserted in the glass pipe, a second optical fiber having one end portion adapted to receive pump light, the second optical fiber being inserted in the glass pipe and fused to the first optical fiber, and a third optical fiber having an output port at one end thereof, the other end of the third optical fiber being inserted in the glass pipe from the output port side of the first optical fiber and fused to the first and second optical fibers. The light amplification coupler further includes a rare earth doped light amplification medium fused to all of the glass pipe and the first, second and third optical fibers in such a manner as to cover the first, second and third optical fibers fused in the glass pipe, and a pump light source for inputting pump light to the one end portion of the second optical fiber.