METHOD FOR CONNECTING OPTICAL FIBER

PURPOSE:To minimize the loss in transmission characteristic caused by temperature change, by hardening the bonding agent while tension is applied to the ends of bare optical fibers to be connected with each other. CONSTITUTION:The cover at the front end section of plastic covered optical fibers 3 and 3' is removed and the ends of bare fibers 1 and 1', whose cover has been removed, are connected with each other and passed through a plastic- made case 6 for reinforcing connected part. The case 6 containing the fibers 3 and 3' and bare fibers 1 and 1' is filled with an epoxy type thermosetting bonding agent, for example, Araldite, and covered with a cap 8. During the course of this process, tension 11 shown by the arrows is applied to the fibers 3 and 3' in the direction of the length with the pair of wide-mouthed gripper of an elastic jig 9 grasping the fibers 3 and 3'. However, this tension is set so that it does not cut off the connected bare fibers 1 and 1'. When the epoxy type thermosetting bonding agent is to be dried quickly, a heater is used. In this way, a connected section which has no bending, namely, which has no loss is realized, because the tension is applied until the bonding agent is hardened at the connected part.