PRODUCTION OF TAPERED OPTICAL FIBER BUNDLE

摘要

PURPOSE:To obtain an optical fiber bundle which is small in the variance of the light distributed to each output optical fiber when said bundle is used for an optical distributor by winding an arraying member to the heated part of plural pieces of the bundled optical fibers, heating the bundled fibers and stretching the same. CONSTITUTION:Plural pieces of the optical fibers 11 are bundled and the arraying member 12 is wound to the heating part thereof. The bundle is then heated and stretched. The homogeneous optical fiber having the refractive index smaller than the refractive index of the clad layer of the fibers 11 is preferably used or a Pt wire or Pt alloy wire is preferably used as the member 12. Since the arraying state of the fibers 11 is held by the arraying member (auxiliary fiber) 12 in the above-mentioned manner, the fibers 11 are surely welded even in the case of a large number of the fibers. No torsion is applied to the fibers in the stage of tapering the same and therefore the light is evenly distributed to all the output optical fibers when the tapered optical fiber bundle obtd. in the above-mentioned manner is used for the optical distributor. The auxiliary fiber to be welded in the stage of tapering has no influence on the optical loss and the arraying member consisting of the Pt wire prevents the intrusion of impurities to the optical fiber bundle and is therefore preferable.