| 摘要 |
PROBLEM TO BE SOLVED: To provide a fiber laser with rare earth element-doped optical fiber as an oscillation medium, an optical coupler capable of efficiently making exciting light from a plurality of excitation light sources incident to an optical fiber amplifier, fiber laser, and an optical fiber amplifier. SOLUTION: There is provided an optical coupler including a first optical coupler having at least two or more exciting light entrance ports and one exit port, formed by melting/integrating or melting/integrating and further extending an optical fiber of this entrance port, so that the exciting light, made incident to the excitation light entrance port, is emitted from a core of the exit port; and a second optical coupler comprising at least two or more exciting light entrance ports and one exit port, formed by melting/integrating or melting/integrating and further extending the optical fiber of this entrance port, so that the core diameter and the number of openings of this exit port are smaller than that of the core diameter and the number of openings of the entrance port of the first optical coupler; and each exit port of a plurality of second optical couplers is connected to the excitation light entrance port of the first optical coupler. COPYRIGHT: (C)2008,JPO&INPIT |
