Optical fibers with composite magnetic coating

Abstract

The goal of these investigations was to define the process parameters that enable the formation of a composite coating with the most uniform thickness on an optical fiber. The composite coating was obtained by drawing the optical fiber through a reservoir with a die at the bottom. The reservoir was supplied with a dispersion of magnetic powder in a polymer solution. The effect of the dispersion viscosity, powder concentration and drawing rate on the uniformity of the composite coating thickness under laboratory conditions was investigated on a defined system to establish the optimal coating conditions. Dispersions were formed by dispersing different concentrations of Ba-ferrite in a poly(ethylene-co-vinyl acetate) solution in toluene. The thickness of the coatings and its uniformity were determined by microscopic analysis and further evaluated by mathematical-statistical analysis. The smallest standard deviation (S.D.) of the mean value of the diameter of the optical fiber with a composite coating was chosen as the criteria for defining the most uniform composite coating. The results show that the most uniform coatings were obtained with a dispersion viscosity whose value was about 1.2 Pa s. All the process parameters should be established in accordance with this viscosity value, enabling the formation of the most uniform composite coating for the investigated system.