Methods for estimating the mechanical stresses distribution in optical fibers

The article considers the effect of bends and mechanical stresses caused by bending on the service life of optical fiber in the cable. It is shown that the bends distribution along the fiber length provides an unambiguous relationship with the distribution of mechanical stresses. A comparative review of modern methods used to control mechanical stresses in optical fibers is presented. The conclusion is drawn that the most promising and inexpensive method to implement for modern single-mode bend-insensitive fibers is the polarization reflectometry based on the analysis of information on the birefringence distribution along the optical fiber length. The factors leading to a change in the magnitude of birefringence during the operation of the optical fiber are determined. The conditions that are necessary to observe when measuring the birefringence distribution along the optical fiber length are presented