Pressure resistant submarine optical fiber cable

Abstract From the Canadian patent

A submarine cable with optical fibers which prevents damage to the fibers without the use of an external armor. The cable has a central strand which provides the cable tensile strength and which is surrounded by helically wound and circumferentially spaced tubes which loosely enclose the optical fibers. Helically wound electrical conductors are intermediate and contact the tubes. A layer of plastic material surrounds the tubes and the electrical conductors. The tubes, any spaces in the strand and any spaces radially inwardly of the layer of plastic material are filled with a substantially incompressible fluid such as a, grease or jelly.