Timothy E. Bishop

Aspects of optical fiber durability

The durability of optical fibers is becoming increasingly important as FITL programs grow. UV cured coatings used to protect optical fibers must be resistant to property changes in a variety of environments. This paper describes the behavior of optical fiber protective coatings when exposed to thermo-oxidative and hydrolytic conditions, actinic radiation, a variety of gel filling compounds, as well as high and low pH solutions. Material property changes are measured through dynamic mechanical analysis and weight loss.

New test method for determining the water sensitivity of optical fiber coatings

Low water sensitivity optical fiber coatings protect optical waveguides from the damaging effects of moisture on static fatigue. The standard test method used to determine the water sensitivity of UV-curable optical fiber coatings does not give a realistic measure of a coatings water sensitivity. The maximum absorption can be reached before 24 h, the extraction continues even after 24 h, and sample pre- and postconditioning greatly influence the results. In the proposed new test method, a number of weight change measurements of samples immersed in water are made as a function of time. Because of the dynamic nature of the test, a more realistic understanding of the water sensitivity of optical fiber coatings is obtained. The effect of different pre- and postconditioning environments is investigated and a recommendation for the best method is made.