OPTICAL FIBER COUPLER, ITS MANUFACTURING METHOD AND MANUFACTURING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an optical fiber coupler with which generation of cross talk is suppressed and excessive loss is made small and to provide its manufacturing method and a manufacturing device. SOLUTION: A pair of polarization maintaining optical fibers 20 is fusion-spliced on both ends of a single mode optical fiber 10 so that cores and polarization main axes are mutually agreed with each other to form an optical fiber. Two of the above optical fibers are stranded and the single mode optical fibers 10 are heated, fused and extended to form an optical fiber coupler 1. A fusion-splicing direction Z in a fusion-spliced portion 11 of the single mode optical fibers 10 and the polarization main axes of the polarization maintaining optical fibers 20 are approximately made into parallel or orthogonal. The polarization mode of the incident light beams at polarization maintaining optical fibers 20A at one side is not changed when the incident light beams pass the single mode optical fibers 10 and are emitted to polarization maintaining optical fibers 20B and the generation of cross talk is suppressed and excessive loss is made small. COPYRIGHT: (C)2006,JPO&NCIPI