Scientists at Prysmian Cables & Systems in Milan, Italy say they have made a significant breakthrough in optical fiber design with the production of a reduced size, 200 micron diameter singlemode...
January 1, 2006
Scientists at Prysmian Cables & Systems in Milan, Italy say they have made a significant breakthrough in optical fiber design with the production of a reduced size, 200 micron diameter singlemode fiber called PrimaLight.
The conventional diameter of optical fibers for telecom use has, for many years, been 250 microns and almost all optical cables use this size of fiber in their construction.
However, as telecom networks continue to develop and the extent of fiber in these networks goes deeper towards the end user, the level of congestion in underground cable ducts, particularly in highly populated urban environments, is becoming a critical issue, the company says.
“Manufacturers have made great efforts to reduce cable diameters through the use of improved manufacturing techniques and enhanced performance materials within the cable construction. This has helped the congestion problem considerably although the lower limits of cable diameter have now realistically been reached.
“Now, by reducing to 200 microns the diameter of the fiber itself — the basic building block of any cable — an additional step-change in cable diameter is possible.”
Agusti Valls, senior vice president of product development and quality for the Prysmian cable business, said it opens up tremendous possibilities on the cable design front.
“With PrimaLight we can now include 16 fibers into a tube element that previously had a limit of 12,” he said. “Alternatively, smaller tubes can be employed to hold similar fiber counts to those used previously.
“The effect on overall cable diameter is significant and for very high fiber count designs — commonly deployed in the access networks — overall diameter reductions exceeding 10% are possible.”