Transient thermal loading induced microbending loss in carbon-coated optical fibers

Abstract

The transient microbending loss in a carbon-coated optical fiber, subjected to time-dependent thermal loading, is analyzed. First, the temperature distributions in the fiber and coating, which are varying with time, are derived. Then, the thermally induced, time-dependent compressive lateral pressure at the interface of the fiber and the coating is obtained. Finally, the transient microbending loss of the carbon-coated fiber is presented. It has been found that the transient microbending loss in the carbon-coated optical fiber increases with increasing Young's modulus, Poisson's ratio, and thermal expansion coefficient of the carbon coating. Therefore, in order to minimize the transient microbending loss of the carbon-coated optical fiber, the Young's modulus, Poisson's ratio, and thermal expansion coefficient of the carbon coating should be decreased. Nevertheless, there exists an optimum value for the thickness of the carbon coating to reduce the transient microbending loss and sustain the mechanical force at the same time.

Inverse estimated transient thermal responses of multicoated optical fiber under time-dependent heat transfer environments

“…Only a few of them considered the case of transient thermal loading. 10,11 . In addition, to simplify the analysis, the convection heat transfer coefficient was taken to be constant, even though the convection coefficient or surrounding temperature might be nonconstant and, instead, is a function of time.…”

Effect of temperature rise and hydrostatic pressure on microbending loss and refractive index change in double-coated optical fiber

“…Beyond some critical limit of thermally induced axial stress, the fiber buckles within the primary coating [2]. The problem of transmission loss of coated optical fibers at low temperature is investigated and reported in literature by number of research workers [3][4][5]. In some reports, the sensitization and desensitization of coated optical fibers due to acoustic waves were analyzed based on phase change of propagating light through the fiber [6][7].…”