A new waterproof optical fiber cable is proposed which used absorbent polymer yarn instead of the conventional jelly-compound as a filling material. This yarn limits the length of water penetration into cable less than 10 cm that is short enough to guarantee long-term reliability. And it is found that the cable has superior characteristics for dynamic bend-tension test.

In order to develop a light and small sized fusion splice machine operating from a small battery, a new high frequency discharge method with high voltage trigger has been developed. The method uses a high voltage trigger at the beginning of discharge to reduce power consumption. It was found experimentally that the voltage of an A-C discharge depends vastly on the applied voltage waveform. To use a high voltage trigger method effectively, pertinent applied voltage conditions were found considering the ion movement. By adopting pertinent conditions, the power consumption for discharge reduces to 1/5 of that for the conventional discharge method. The new method is adopted for developing a fusion splice in optical fibers. The developed machine is 2.5 kg in weight including battery, and consumes 25 watts electric power. The average splice loss and splice tension strength are 0.03 dB and 480 g, respectively.

This letter proposes a new optical cable which can be manufactured in a single process. The basic structural design has been made in view of an excess fiber length ratio to the cable length. The fabricated cable has exhibited sufficient transmission and mechanical characteristics.