Submarine optical cable, optical fiber unit employed in the submarine optical cable, and method of making optical fiber unit

Abstract

The present invention relates to a wide-band, low-loss, submarine optical cable excellent in productivity, an optical fiber unit employed in the submarine optical cable, and a method of making the optical fiber unit. The optical fiber unit employed in the submarine optical cable comprises a loose structure in which one or more coated optical fibers are accommodated together with a soft resin in a space formed within a plastic support. In particular, one or more compression members are embedded in the plastic support along the space accommodating the coated optical fibers. The compression members closely in contact with the plastic support prevents the shrinkage of the plastic support from occurring due to temperature changes before forming a cable utilizing the optical fiber unit. Preventing the shrinkage of the plastic support from occurring before forming the cable suppresses the increase in surplus length ratio of the accommodated coated optical fibers, thereby effectively restraining the transmission loss of the submarine optical cable from increasing due to the increase in surplus length ratio.